DAC5682Z [TI]

16-BIT, 1.0 GSPS 2x-4x INTERPOLATING DUAL-CHANNEL DIGITAL-TO-ANALOG CONVERTER (DAC); 16位, 1.0 GSPS 2倍, 4倍内插双通道数位类比转换器( DAC )
DAC5682Z
型号: DAC5682Z
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

16-BIT, 1.0 GSPS 2x-4x INTERPOLATING DUAL-CHANNEL DIGITAL-TO-ANALOG CONVERTER (DAC)
16位, 1.0 GSPS 2倍, 4倍内插双通道数位类比转换器( DAC )

转换器
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DAC5682Z  
www.ti.com  
SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
16-BIT, 1.0 GSPS 2x-4x INTERPOLATING DUAL-CHANNEL  
DIGITAL-TO-ANALOG CONVERTER (DAC)  
1
FEATURES  
DESCRIPTION  
16-Bit Digital-to-Analog Converter (DAC)  
1.0 GSPS Update Rate  
The DAC5682Z is a dual-channel 16-bit 1.0 GSPS  
digital-to-analog converter (DAC) with wideband  
LVDS data input, integrated 2x/4x interpolation filters,  
on-board clock multiplier and internal voltage  
reference. The DAC5682Z offers superior linearity,  
noise, crosstalk and PLL phase noise performance.  
16-Bit Wideband Input LVDS Data Bus  
8 Sample Input FIFO  
Interleaved I/Q data for Dual-DAC Mode  
High Performance  
73 dBc ACLR WCDMA TM1 at 180 MHz  
The DAC5682Z integrates a wideband LVDS port  
with on-chip termination. Full-rate input data can be  
transferred to a single DAC channel, or half-rate and  
1/4-rate input data can be interpolated by on-board  
2x or 4x FIR filters. Each interpolation FIR is  
configurable in either Low-Pass or High-Pass mode,  
allowing selection of a higher order output spectral  
image. An on-chip delay lock loop (DLL) simplifies  
LVDS interfacing by providing skew control for the  
LVDS input data clock.  
2x-32x Clock Multiplying PLL/VCO  
2x or 4x Interpolation Filters  
Stopband Transition 0.4–0.6 Fdata  
Filters Configurable in Either Low-Pass or  
High-Pass Mode  
Allows Selection of Higher Order Image  
Fs/4 Coarse Mixer  
On Chip 1.2 V Reference  
The DAC5682Z allows both complex or real output.  
An optional Fs/4 coarse mixer in complex mode  
provides coarse frequency upconversion and the dual  
DAC output produces a complex Hilbert Transform  
pair. An external RF quadrature modulator then  
performs the final single sideband up-conversion.  
Differential Scalable Output: 2 to 20 mA  
Package: 64-Pin 9 × 9 mm QFN  
APPLICATIONS  
Cellular Base Stations  
Broadband Wireless Access (BWA)  
WiMAX 802.16  
Fixed Wireless Backhaul  
Cable Modem Termination System (CMTS)  
The DAC5682Z is characterized for operation over  
the industrial temperature range of –40°C to 85°C  
and is available in a 64-pin QFN package. Other  
single-channel members of the family include the  
interpolating DAC5681Z  
DAC5681.  
and non-interpolating  
ORDERING INFORMATION  
TA  
ORDER CODE  
DAC5682ZIRGCT  
DAC5682ZIRGCR  
PACKAGE DRAWING/TYPE(1)(2)(3)  
TRANSPORT MEDIA  
Small Tape and Reel  
Large Tape and Reel  
QUANTITY  
250  
RGC / 64QFN Quad Flatpack  
No-Lead  
–40°C to 85°C  
2000  
(1) Thermal Pad Size: 7,4 mm × 7,4 mm  
(2) MSL Peak Temperature: Level-3-260C-168 HR  
(3) For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI  
website at www.ti.com.  
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of  
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.  
PRODUCTION DATA information is current as of publication date.  
Copyright © 2007, Texas Instruments Incorporated  
Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
DAC5682Z  
www.ti.com  
SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam  
during storage or handling to prevent electrostatic damage to the MOS gates.  
FUNCTIONAL BLOCK DIAGRAM  
PLL Bypass  
CLKIN  
FDAC  
EXTIO  
1.2V  
Reference  
Clock Multiplying  
PLL 2x-32x  
Clock  
Distribution  
FDAC/2  
FDAC/4  
EXTLO  
BIASJ  
CLKINC  
DCLKP  
PLL Control  
DLL Control  
PLL Enable  
(x2 Bypass)  
Sync Disable  
Delay Lock  
Loop (DLL)  
DACA_gain  
Mode Control  
(x1 Bypass)  
DCLKN  
4
A-Offset  
13  
A
B
D15P  
D15N  
IOUTA1  
IOUTA2  
16bit  
DAC  
x2  
47t 76dB HBF  
x2  
47t 76dB HBF  
16  
16  
FIR0  
FIR1  
D0P  
D0N  
IOUTB1  
IOUTB2  
16bit  
DAC  
x2  
47t 76dB HBF  
x2  
47t 76dB HBF  
16  
16  
2
13  
2
2
e
e
SYNC=’0->1'  
(transition)  
e
l
e
e
u
b
l
4
d
d
SYNCP  
SYNCN  
a
a
t
o
o
n
e
V
E
M
M
s
f
y
DACB_gain  
f
1
0
1
a
l
TXEnable=’1'  
O
R
R
M
M
e
-
I
I
F
C
F
C
B
D
SW_Sync  
FIFO Sync Disable  
Sync & Control  
2
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Copyright © 2007, Texas Instruments Incorporated  
Product Folder Link(s): DAC5682Z  
DAC5682Z  
www.ti.com  
SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
DAC5682Z  
RGC PACKAGE  
(TOP VIEW)  
1
48  
47  
46  
45  
44  
43  
42  
41  
40  
39  
38  
37  
36  
35  
34  
33  
SDENB  
SCLK  
SDIO  
SDO  
VFUSE  
D0N  
CLKVDD  
CLKIN  
2
3
CLKINC  
GND  
4
5
SYNCP  
6
SYNCN  
D15P  
7
D0P  
8
D15N  
D1N  
DAC5682Z  
9
IOVDD  
D1P  
10  
11  
12  
13  
14  
15  
16  
DVDD  
D2N  
DVDD  
D14P  
D14N  
D13P  
D13N  
D12P  
D12N  
D2P  
D3N  
D3P  
D4N  
D4P  
TERMINAL FUNCTIONS  
TERMINAL  
I/O  
DESCRIPTION  
NAME  
AVDD  
BIASJ  
NO.  
51, 54, 55,  
59, 62  
Analog supply voltage. (3.3V)  
I
57  
O
Full-scale output current bias. For full-scale output current, connect a 960 resistor to GND.  
Positive external clock input with a self-bias of approximately CLKVDD/2. With the clock multiplier PLL  
enabled, CLKIN provides lower frequency reference clock. If the PLL is disabled, CLKIN directly provides  
clock for DAC up to 1GHz.  
CLKIN  
2
I
CLKINC  
3
1
I
I
Complementary external clock input. (See the CLKIN description)  
Internal clock buffer supply voltage. (1.8 V)  
CLKVDD  
LVDS positive input data bits 0 through 15. Each positive/negative LVDS pair has an internal 100 Ω  
termination resistor. Order of bus can be reversed via rev_bus bit in CONFIG5 register. Data format relative  
to DCLKP/N clock is Double Data Rate (DDR) with two data samples input per DCLKP/N clock. In  
dual-channel mode, data for the A-channel is input while DCLKP is high.  
7, 11, 13,  
15, 17, 19,  
21, 23, 27,  
29, 31, 33,  
35, 37, 40,  
42  
D[15..0]P  
I
D15P is most significant data bit (MSB) – pin 7  
D0P is least significant data bit (LSB) – pin 42  
Copyright © 2007, Texas Instruments Incorporated  
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DAC5682Z  
www.ti.com  
SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
TERMINAL FUNCTIONS (continued)  
TERMINAL  
I/O  
DESCRIPTION  
NAME  
NO.  
8, 12, 14,  
16, 18, 20,  
22, 24, 28,  
30, 32, 34,  
36, 38, 41,  
43  
LVDS negative input data bits 0 through 15. (See D[15:0]P description above)  
D15N is most significant data bit (MSB) – pin 8  
D0N is least significant data bit (LSB) – pin 43  
D[15..0]N  
I
LVDS positive input clock. Unlike the other LVDS inputs, the DCLKP/N pair is self-biased to approximately  
DVDD/2 and does not have an internal termination resistor in order to optimize operation of the DLL circuit.  
See the “DLL Operation” section. For proper external termination, connect a 100 resistor across LVDS  
clock source lines followed by series 0.01 µF capacitors connected to each of DCLKP and DCLKN pins (see  
Figure 26). For best performance, the resistor and capacitors should be placed as close as possible to these  
pins.  
DCLKP  
25  
26  
I
DCLKN  
DVDD  
I
I
LVDS negative input clock. (See the DCLKP description)  
Digital supply voltage. (1.8 V)  
10, 39, 50,  
63  
Used as external reference input when internal reference is disabled (i.e., EXTLO connected to AVDD).  
EXTIO  
56  
58  
I/O Used as 1.2V internal reference output when EXTLO = GND, requires a 0.1 µF decoupling capacitor to  
AGND when used as reference output.  
EXTLO  
GND  
O
I
Internal reference ground. Connect to AVDD to disable the internal reference.  
4, Thermal  
Pad  
Pin 4 and the Thermal Pad located on the bottom of the QFN package is ground for AVDD, DVDD and  
IOVDD supplies.  
A-Channel DAC current output. An offset binary data pattern of 0x0000 at the DAC input results in a full  
scale current sink and the least positive voltage on the IOUTA1 pin. Similarly, a 0xFFFF data input results in  
a 0 mA current sink and the most positive voltage on the IOUTA1 pin. In single DAC mode, outputs appear  
on the IOUTA1/A2 pair only.  
IOUTA1  
52  
O
A-Channel DAC complementary current output. The IOUTA2 has the opposite behavior of the IOUTA1  
described above. An input data value of 0x0000 results in a 0mA sink and the most positive voltage on the  
IOUTA2 pin.  
IOUTA2  
53  
O
IOUTB1  
IOUTB2  
IOVDD  
61  
60  
9
O
O
I
B-Channel DAC current output. See the IOUTA1 description above.  
B-Channel DAC complementary current output. See the IOUTA2 description above.  
Digital I/O supply voltage (3.3V) for pins RESETB, SCLK, SDENB, SDIO, SDO.  
PLL loop filter connection. If not using the clock multiplying PLL, the LPF pin may be left open. Set both  
PLL_bypass and PLL_sleep control bits for reduced power dissipation.  
LPF  
64  
I
RESETB  
SCLK  
49  
47  
48  
46  
I
I
I
Resets the chip when low. Internal pull-up.  
Serial interface clock. Internal pull-down.  
SDENB  
SDIO  
Active low serial data enable, always an input to the DAC5682Z. Internal pull-up.  
I/O Serial interface data, bi-directional. Default setting sets SDIO as an input. Internal pull-down.  
Serial interface data, uni-directional data output, if SDIO is an input. SDO is 3-stated when the 3 pin interface  
mode is selected (register 0x08 bit 1). Internal pull-down.  
SDO  
45  
O
LVDS SYNC positive input data. The SYNCP/N LVDS pair has an internal 100 termination resistor. By  
SYNCP  
5
I
default, the SYNCP/N input must be logic ‘1’ to enable a DAC analog output. See the LVDS SYNCP/N  
Operation paragraph for a detailed description.  
SYNCN  
VFUSE  
6
I
I
LVDS SYNC negative input data.  
Digital supply voltage. (1.8V) Connect to DVDD pins for normal operation. This supply pin is also used for  
factory fuse programming.  
44  
4
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DAC5682Z  
www.ti.com  
SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
ABSOLUTE MAXIMUM RATINGS  
over operating free-air temperature range (unless otherwise noted)  
(1)  
VALUE  
–0.5 to 2.3  
UNIT  
V
DVDD(2)  
CLKVDD(2)  
AVDD(2)  
–0.5 to 2.3  
V
Supply voltage range  
–0.5 to 4  
V
IOVDD(2)  
Voltage between GND, and CLKGND  
AVDD to DVDD  
–0.5 to 4  
V
–0.5 to 0.5  
V
–2 to 2.6  
V
CLKVDD to DVDD  
–0.5 to 0.5  
V
IOVDD to AVDD  
–0.5 to 0.5  
V
(2)  
D[15..0]P ,D[15..0]N, SYNCP, SYNCN  
DCLKP, DCLKN(2)  
–0.5 to DVDD + 0.5  
–0.3 to 2.1  
V
Supply voltage range  
V
CLKIN, CLKINC(2)  
–0.5 to CLKVDD + 0.5  
–0.5 to IOVDD + 0.5  
–0.5 to AVDD + 0.5  
–0.5 to AVDD + 0.5  
20  
V
(2)  
SDO, SDIO, SCLK, SDENB, RESETB  
V
(2)  
IOUTA1/B1, IOUTA2/B2  
LPF, EXTIO, EXTLO, BIASJ(2)  
V
V
Peak input current (any input)  
mA  
mA  
°C  
°C  
Peak total input current (all inputs)  
–30  
Operating free-air temperature range, TA: DAC5682ZI  
Storage temperature range  
–40 To 85  
–65 To 150  
(1) Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings  
only, and functional operation of these or any other conditions beyond those indicated under recommended operating conditions is not  
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.  
(2) Measured with respect to GND.  
THERMAL CHARACTERISTICS  
over operating free-air temperature range (unless otherwise noted)  
THERMAL CONDUCTIVITY  
64ld QFN  
UNIT  
(1)  
TJ  
Maximum junction temperature  
125  
20  
16  
7
°C  
Theta junction-to-ambient (still air)  
Theta junction-to-ambient (150 lfm)  
Theta junction-to-case  
θJA  
°C/W  
θJC  
θJP  
°C/W  
°C/W  
Theta junction-to-pad  
0.2  
(1) Air flow or heat sinking reduces θJA and may be required for sustained operation at 85° under maximum operating conditions.  
Copyright © 2007, Texas Instruments Incorporated  
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DAC5682Z  
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SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
ELECTRICAL CHARACTERISTICS — DC SPECIFICATION  
over operating free-air temperature range , AVDD = 3.3 V, CLKVDD = 1.8 V, IOVDD = 3.3 V, DVDD = 1.8 V, IoutFS = 20 mA  
(unless otherwise noted)  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
Resolution  
DC ACCURACY(1)  
16  
Bits  
INL  
Integral nonlinearity  
Differential nonlinearity  
1 LSB = IOUTFS/216  
±4  
±2  
LSB  
DNL  
ANALOG OUTPUT  
Course gain linearity  
±0.04  
0.01  
1
LSB  
Offset error  
Mid code offset  
%FSR  
%FSR  
%FSR  
%FSR  
Gain error  
Without internal reference  
With internal reference  
Gain error  
0.7  
Gain mismatch  
With internal reference, dual DAC, SSB mode  
–2  
2
Minimum full scale output current(2)  
Maximum full scale output current(2)  
2
mA  
V
20  
AVDD  
–0.5V  
AVDD  
+ 0.5V  
Output Compliance range(3)  
IOUTFS = 20 mA  
Output resistance  
Output capacitance  
300  
5
kΩ  
pF  
REFERENCE OUTPUT  
Vref  
Reference voltage  
Reference output current(4)  
1.14  
0.1  
1.2  
1.26  
1.25  
V
100  
nA  
REFERENCE INPUT  
VEXTIO Input voltage range  
V
Input resistance  
1
95  
MΩ  
CONFIG6: BiasLPF_A and BiasLPF = 1  
CONFIG6: BiasLPF_A and BiasLPF = 0  
Small signal bandwidth  
Input capacitance  
kHz  
pF  
472  
100  
TEMPERATURE COEFFICIENTS  
ppm of  
FSR/°C  
Offset drift  
±1  
Without internal reference  
With internal reference  
±15  
±30  
±8  
ppm of  
FSR/°C  
Gain drift  
Reference voltage drift  
POWER SUPPLY  
ppm/°C  
Analog supply voltage, AVDD  
Digital supply voltage, DVDD  
Clock supply voltage, CLKVDD  
I/O supply voltage, IOVDD  
3.0  
1.71  
1.71  
3.0  
3.3  
1.8  
1.8  
3.3  
133  
455  
45  
3.6  
2.15  
2.15  
3.6  
V
V
V
V
I(AVDD)  
I(DVDD)  
Analog supply current  
Digital supply current  
mA  
mA  
mA  
mA  
Mode 4 (below)  
I(CLKVDD) Clock supply current  
I(IOVDD) IO supply current  
12  
(1) Measured differential across IOUTA1 and IOUTA2 or IOUTB1 and IOUTB2 with 25 each to AVDD.  
(2) Nominal full-scale current, IoutFS, equals 16 × IBIAS current.  
(3) The lower limit of the output compliance is determined by the CMOS process. Exceeding this limit may result in transistor breakdown,  
resulting in reduced reliability of the DAC5682Z device. The upper limit of the output compliance is determined by the load resistors and  
full-scale output current. Exceeding the upper limit adversely affects distortion performance and integral nonlinearity.  
(4) Use an external buffer amplifier with high impedance input to drive any external load.  
6
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DAC5682Z  
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SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
ELECTRICAL CHARACTERISTICS — DC SPECIFICATION (continued)  
over operating free-air temperature range , AVDD = 3.3 V, CLKVDD = 1.8 V, IOVDD = 3.3 V, DVDD = 1.8 V, IoutFS = 20 mA  
(unless otherwise noted)  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
1.0  
MAX  
UNIT  
mA  
I(AVDD)  
I(DVDD)  
Sleep mode, AVDD supply current  
Sleep mode, DVDD supply current  
1.5  
mA  
Mode 6 (below)  
Sleep mode, CLKVDD supply  
current  
I(CLKVDD)  
I(IOVDD)  
2.5  
mA  
Sleep mode, IOVDD supply current  
AVDD + IOVDD current, 3.3V  
DVDD + CLKVDD current, 1.8V  
Power Dissipation  
2.0  
135  
450  
1255  
145  
485  
1350  
135  
480  
1310  
145  
505  
1400  
5
mA  
mA  
mA  
mW  
mA  
mA  
mW  
mA  
mA  
mW  
mA  
mA  
mW  
mA  
mA  
mW  
mA  
mA  
mW  
Mode 1: 2X2, PLL = OFF, CLKIN = 983.04 MHz  
FDAC = 983.04MHz, IF = 184.32 MHz  
DACA and DACB ON, 4 carrier WCDMA  
AVDD + IOVDD current, 3.3V  
DVDD + CLKVDD current, 1.8V  
Power Dissipation  
Mode 2: 2X2, PLL = ON (8X), CLKIN = 122.88  
MHz  
FDAC = 983.04MHz, IF = 184.32 MHz  
DACA and DACB ON, 4 carrier WCDMA  
AVDD + IOVDD current, 3.3V  
DVDD + CLKVDD current, 1.8V  
Power Dissipation  
Mode 3: 2X4, CMIX0 = Fs/4, PLL = OFF, CLKIN =  
983.04 MHz  
FDAC = 983.04MHz, IF = 215.04 MHz  
DACA and DACB ON, 4 carrier WCDMA  
P
AVDD + IOVDD current, 3.3V  
DVDD + CLKVDD current, 1.8V  
Power Dissipation  
Mode 4: 2X4, CMIX0 = Fs/4, PLL = ON (8X),  
CLKIN = 122.88 MHz  
FDAC = 983.04MHz, IF = 215.04 MHz  
DACA and DACB ON, 4 carrier WCDMA  
1600  
AVDD + IOVDD current, 3.3V  
DVDD + CLKVDD current, 1.8V  
Power Dissipation  
Mode 5: 2X2, CMIX0 = Fs/4, PLL = OFF, CLKIN =  
983.04 MHz  
FDAC = 983.04MHz, Digital Logic Disabled  
DACA and DACB SLEEP, Static Data Pattern  
185  
350  
3.0  
AVDD + IOVDD current, 3.3V  
DVDD + CLKVDD current, 1.8V  
Power Dissipation  
Mode 6: 2X4, PLL = OFF, CLKIN = OFF  
FDAC = OFF, Digital Logic Disabled  
DACA and DACB = SLEEP, Static Data Pattern  
4.0  
17.0  
30.0  
0.2 %FSR/V  
85 °C  
PSSR  
T
Power supply rejection ratio  
Operating range  
–2  
–40  
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SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
ELECTRICAL CHARACTERISTICS — AC SPECIFICATION(1)  
Over recommended operating free-air temperature range, AVDD, IOVDD = 3.3 V, CLKVDD, DVDD = 1.8 V, IOUTFS = 20 mA,  
4:1 transformer output termination, 50doubly terminated load (unless otherwise noted)  
PARAMETER  
ANALOG OUTPUT  
TEST CONDITIONS  
MIN  
TYP MAX UNIT  
Maximum output update  
rate  
fCLK  
1000  
MSPS  
Output settling time to  
0.1%  
Transition: Code 0x0000 to 0xFFFF  
ts(DAC)  
tpd  
10.4  
3
ns  
ns  
ns  
Output propagation delay  
Output rise time 10% to  
90%  
tr(IOUT)  
2
Output fall time 90% to  
10%  
tf(IOUT)  
2
ns  
AC PERFORMANCE  
1X1, PLL off, CLKIN = 500 MHz, DACA on, IF = 5.1 MHz,  
First Nyquist Zone < fDATA/2  
81  
80  
77  
73  
69  
63  
60  
60  
73  
81  
72  
64  
64  
83  
73  
66  
63  
93  
85  
Spurious free dynamic  
range  
2X2, PLL off, CLKIN = 1000 MHz, DACA and DACB on,  
IF = 5.1 MHz, First Nyquist Zone < fDATA/2  
SFDR  
dBc  
2X2, PLL off, CLKIN = 1000 MHz, DACA and DACB on,  
IF = 20.1 MHz, First Nyquist Zone < fDATA/2  
2X2, PLL off, CLKIN = 500 MHZ, DACA and DACB on, Single tone,  
0 dBFS, IF = 20.1 MHz  
2X2, PLL off, CLKIN = 1000 MHZ, DACA and DACB on, Single  
tone, 0 dBFS, IF = 20.1 MHz  
2X2, PLL off, CLKIN = 1000 MHZ, DACA and DACB on, Single  
tone, 0 dBFS, IF = 70.1 MHz  
SNR  
Signal-to-noise ratio  
dBc  
2X4, PLL off, CLKIN = 1000 MHZ, DACA and DACB on, Single  
tone, 0 dBFS, IF = 180 MHz  
2X2 CMIX, PLL off, CLKIN = 1000 MHZ, DACA and DACB on,  
Single tone, 0 dBFS, IF = 300.2 MHz  
2X2, PLL off, CLKIN = 1000 MHZ, DACA and DACB on, Four tone,  
each -12 dBFS, IF = 24.7, 24.9, 25.1 and 25.3 MHz  
2X2, PLL off, CLKIN = 1000 MHZ, DACA and DACB on,  
IF = 20.1 and 21.1 MHz  
Third-order two-tone  
intermodulation (each  
tone at –6 dBFS)  
2X2, PLL off, CLKIN = 1000 MHZ, DACA and DACB on,  
IF = 70.1 and 71.1 MHz  
IMD3  
IMD  
dBc  
dBc  
2X2 CMIX, PLL off, CLKIN = 1000 MHZ, DACA and DACB on,  
IF = 150.1 and 151.1 MHz  
Four-tone intermodulation 2X2 CMIX, PLL off, CLKIN = 1000 MHz, DACA and DACB on,  
(each tone at –12 dBFS)  
fOUT = 298.4, 299.2, 300.8 and 301.6 MHz  
Single carrier, baseband, 2X2, PLL off, CLKIN = 983.04 MHz,  
DACA and DACB on(3)  
80  
Single carrier, IF = 180 MHz, 2X2, PLL off,  
CLKIN = 983.04 MHz, DACA and DACB on  
Adjacent channel leakage  
ratio  
ACLR(2)  
dBc  
dBc  
Four carrier, IF = 180 MHz, 2X2 CMIX, PLL off,  
CLKIN = 983.04 MHz, DACA and DACB on  
Four carrier, IF = 275 MHz, 2X2 CMIX, PLL off,  
CLKIN = 983.04 MHz, DACA and DACB on  
50-MHz offset, 1-MHz BW, Single Carrier, baseband, 2X2, PLL off,  
CLKIN = 983.04  
Noise floor(4)  
50-MHz offset, 1-MHz BW, Four Carrier, baseband, 2X2, PLL off,  
CLKIN = 983.04.  
(1) Measured single-ended into 50 load.  
(2) W-CDMA with 3.84 MHz BW, 5-MHz spacing, centered at IF. TESTMODEL 1, 10 ms  
(3) Valid over 25°C to 85°C  
(4) Carrier power measured in 3.84 MHz BW.  
8
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SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
ELECTRICAL CHARACTERISTICS (DIGITAL SPECIFICATIONS)  
over recommended operating free-air temperature range, AVDD, IOVDD = 3.3V, CLKVDD, DVDD = 1.8V.  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
LVDS INTERFACE: D[15:0]P, D[15:0]N, SYNCP/N, DCLKP/N  
Positive-going  
175  
VITH+  
differential input  
voltage threshold  
mV  
mV  
Negative-going  
differential input  
voltage threshold  
–175  
1.2  
VITH–  
Input Common  
Mode  
SYNCP/N, D[15:0]P and D[15:0]N only  
DCLKP/N only  
VCOM1  
V
V
Input Common  
Mode  
DVDD/  
2
VCOM2  
ZT  
Internal termination SYNCP/N, D[15:0]P and D[15:0]N only  
100  
110  
120  
LVDS Input  
capacitance  
CL  
2
pF  
DCLKP/N: 0 to 125MHz (see Figure 33)  
DCLK to Data  
Setup_min  
Hold_min  
Positive  
Negative  
Positive  
Negative  
Positive  
Negative  
Positive  
Negative  
Positive  
Negative  
Positive  
Negative  
Positive  
Negative  
Positive  
1100  
–600  
1000  
–1800  
800  
tS, tH  
CONFIG5 DLL_bypass = 1, CONFIG10 = '00000000'  
DCLKP/N = 150MHz  
CONFIG5 DLL_bypass = 0,  
DCLKP/N = 200MHz  
CONFIG5 DLL_bypass = 0  
–1300  
600  
DCLKP/N = 250MHz  
CONFIG5 DLL_bypass = 0  
–1000  
450  
DCLK to Data  
Skew(1)  
DCLKP/N = 300MHz  
CONFIG5 DLL_bypass = 0  
ps  
–800  
400  
tSKEW(A), [Please contact  
DCLKP/N = 350 MHz  
tSKEW(B)  
factory for  
CONFIG5 DLL_bypass = 0  
recommended DLL  
settings]  
–700  
300  
DCLKP/N = 400 MHz CONFIG5 DLL_bypass = 0  
Refer to supported data rate [fDATA  
]
–600  
300  
DCLKP/N = 450 MHz CONFIG5 DLL_bypass = 0  
Refer to supported data rate [fDATA  
]
–500  
350  
DCLKP/N = 500 MHz, T = 25 °C to 85 °C CONFIG5  
DLL_bypass = 0  
Negative  
–300  
Refer to supported data rate [fDATA  
]
DLL Enabled, T = 25 °C to 85 °C  
DDR format, DCLKP frequency: 125 to 500 MHz  
250  
250  
1000  
Input data rate  
supported  
DLL Enabled, T = –40 °C  
DDR format, DCLK frequency: 125 to 375 MHz  
fDATA  
750 MSPS  
250  
DLL Disabled, T = –40 °C to 85 °C  
DDR format, DCLKP frequency: <125 MHz  
CMOS INTERFACE: SDO, SDIO, SCLK, SDENB, RESETB  
High-level input  
voltage  
2
0
3
0
VIH  
V
Low-level input  
voltage  
0.8  
V
VIL  
High-level input  
current  
–40  
–40  
40  
IIH  
µA  
Low-level input  
current  
40  
IIL  
µA  
CMOS Input  
capacitance  
5
CI  
pF  
(1) Positive skew: Clock ahead of data.  
Negative skew: Data ahead of clock.  
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SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
ELECTRICAL CHARACTERISTICS (DIGITAL SPECIFICATIONS) (continued)  
over recommended operating free-air temperature range, AVDD, IOVDD = 3.3V, CLKVDD, DVDD = 1.8V.  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
IOVDD  
– 0.2  
Iload = –100 µA  
V
VOH  
SDO, SDIO  
0.8 x  
IOVDD  
Iload = –2mA  
Iload = 100 µA  
Iload = 2 mA  
V
0.2  
V
V
VOL  
SDO, SDIO  
Setup time,  
0.22 x  
IOVDD  
ts(SDENB) SDENB to rising  
edge of SCLK  
20  
10  
5
ns  
ns  
ns  
Setup time, SDIO  
ts(SDIO)  
valid to rising edge  
of SCLK  
Hold time, SDIO  
valid to rising edge  
of SCLK  
th(SDIO)  
t(SCLK)  
t(SCLKH)  
t(SCLK)  
Period of SCLK  
100  
40  
ns  
ns  
ns  
High time of SCLK  
Low time of SCLK  
40  
Data output delay  
after falling edge of  
SCLK  
td(Data)  
10  
25  
ns  
ns  
Minimum RESETB  
pulse width  
tRESET  
CLOCK INPUT (CLKIN/CLKINC)  
Duty cycle  
50%  
1
Differential voltage  
0.5  
V
V
CLKIN/CLKINC  
input common  
mode  
CLKVD  
D/2  
PHASE LOCKED LOOP  
DAC output at 600 kHz offset, 100 MHz, 0-dBFS tone,  
2X4, fDATA = 250 MSPS, CLKIN/C = 250 MHz,  
PLL_m = '00111', PLL_n = '001', VCO_div2 = 0,  
PLL_range = '1111', PLL_gain = '00'  
–125  
–146  
Phase noise  
dBc/ Hz  
DAC output at 6 MHz offset, 100 MHz, 0-dBFS tone,  
2X4, fDATA = 250 MSPS, CLKIN/C = 250 MHz,  
PLL_m = '00111', PLL_n = '001', VCO_div2 = 0,  
PLL_range = '1111', PLL_gain = '00'  
10  
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SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
ELECTRICAL CHARACTERISTICS (DIGITAL SPECIFICATIONS) (continued)  
over recommended operating free-air temperature range, AVDD, IOVDD = 3.3V, CLKVDD, DVDD = 1.8V.  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
220  
300  
260  
240  
210  
270  
250  
240  
220  
210  
250  
230  
220  
210  
200  
MAX UNIT  
PLL_gain = '00', PLL_range = '0000' (0)  
160  
290  
MHz  
MHz/V  
MHz  
PLL_gain = '01', PLL_range = '0001' (1)  
PLL_gain = '01', PLL_range = '0010' (2)  
PLL_gain = '01', PLL_range = '0011' (3)  
PLL_gain = '01', PLL_range = '0100' (4)  
PLL_gain = '10', PLL_range = '0101' (5)  
PLL_gain = '10', PLL_range = '0110' (6)  
PLL_gain = '10', PLL_range = '0111' (7)  
PLL_gain = '10', PLL_range = '1000' (8)  
PLL_gain = '10', PLL_range = '1001' (9)  
PLL_gain = '11', PLL_range = '1010' (A)  
PLL_gain = '11', PLL_range = '1011' (B)  
PLL_gain = '11', PLL_range = '1100' (C)  
PLL_gain = '11', PLL_range = '1101' (D)  
PLL_gain = '11', PLL_range = '1110' (E)  
PLL_gain = '11', PLL_range = '1111' (F)  
290  
400  
480  
560  
620  
690  
740  
790  
840  
880  
920  
960  
1000  
1030  
1060  
460  
MHz/V  
MHz  
520  
MHz/V  
MHz  
570  
MHz/V  
MHz  
620  
MHz/V  
MHz  
740  
MHz/V  
MHz  
780  
MHz/V  
MHz  
820  
PLL/VCO  
Operating  
Frequency,  
Typical VCO Gain  
MHz/V  
MHz  
850  
MHz/V  
MHz  
880  
MHz/V  
MHz  
940  
MHz/V  
MHz  
990  
MHz/V  
MHz  
1020  
1040  
1070  
1090  
MHz/V  
MHz  
MHz/V  
MHz  
MHz/V  
MHz  
190  
160  
MHz/V  
PFD Maximum  
Frequency  
MHz  
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SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
TYPICAL CHARACTERISTICS  
10  
10  
8
8
6
6
4
4
2
0
2
0
-2  
-4  
-6  
-2  
-4  
-6  
-8  
-8  
-10  
-10  
0
10000 20000 30000 40000 50000 60000  
0
10000 20000 30000 40000 50000 60000  
Code  
Code  
Figure 1. Integral Nonlinearity  
Figure 2. Differential Nonlinearity  
10  
10  
0
F
F
I
= 250 MSPS,  
F
F
I
= 250 MSPS,  
data  
data  
0
-10  
-20  
-30  
-40  
-50  
= 20 MHz Complex,  
= 20 MHz Complex,  
IN  
IN  
= 270 MHz,  
= 20 MHz,  
-10  
-20  
-30  
-40  
-50  
F
F
x4 Interpolation  
PLL Off  
x4 Interpolation  
CMIX F /4  
S
PLL Off  
-60  
-70  
-60  
-70  
-80  
-90  
-80  
-90  
0
50 100 150 200 250 300 350 400 450 500  
f - Frequency - MHz  
0
50 100 150 200 250 300 350 400 450 500  
f - Frequency - MHz  
Figure 3. Single-Tone Spectral Plot  
Figure 4. Single-Tone Spectral Plot  
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SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
TYPICAL CHARACTERISTICS (continued)  
95  
90  
85  
80  
75  
70  
10  
F
F
= 250 MSPS,  
F
= 250 MSPS,  
data  
data  
x4 Interpolation,  
PLL Off  
0
= -80 MHz Complex,  
IN  
(-80+250=170)  
= 170 MHz, CMIX, F /4  
-10  
I
F
S
x4 Interpolation  
PLL Off  
-20  
-30  
-6 dBFS  
-12 dBFS  
-40  
-50  
-60  
-70  
-80  
0 dBFS  
65  
60  
0
10  
20  
30  
40  
50  
0
50 100 150 200 250 300 350 400 450 500  
f - Frequency - MHz  
IF - Intermediate Frequency - MHz  
Figure 5. Single-Tone Spectral Plot  
Figure 6. In-Band SFDR vs IF  
90  
85  
90  
F
= 250 MSPS,  
F
= 250 MSPS,  
data  
x4 Interpolation,  
PLL Off  
data  
x4 Interpolation,  
PLL Off  
85  
80  
75  
70  
65  
60  
55  
50  
80  
75  
70  
65  
60  
55  
50  
45  
40  
0
40  
80 120 160 200 240 280 320  
IF - Intermediate Frequency - MHz  
0
50 100 150 200 250 300 350 400 450 500  
IF - Intermediate Frequency - MHz  
Figure 7. Out-Of-Band SFDR vs IF  
Figure 8. Two Tone IMD vs Output Frequency  
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SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
TYPICAL CHARACTERISTICS (continued)  
0
85  
80  
89.5 and 90.5 MHz  
(CMIX Off)  
F
F
I
= 500 MSPS,  
data  
-10  
= 40 0.5 MHz Real,  
IN  
= 40 MHz,  
F
-20  
-30  
-40  
-50  
-60  
-70  
-80  
x2 Interpolation  
PLL Off  
75  
70  
65  
Shift to 340 MHz  
(F /8 On)  
S
Shift to 215 MHz  
(F /4 On)  
60  
55  
S
F
F
= 250 MSPS  
data  
= 90 MHz 0.5 MHz Compleꢀ  
in  
50  
45  
ꢀ4 Interpolation, PLL Off  
Three modes: CMIX, F /8, and F /4  
-90  
S
S
-100  
35 36 37 38 39 40 41 42 43 44 45  
f - Frequency - MHz  
-30  
-25  
-20  
Amplitude - dBFS  
Figure 9. Two Tone IMD vs Amplitude  
-15  
-10  
-5  
0
Figure 10. Two-Tone IMD Spectral Plot  
10  
0
85  
80  
Fdata = 500 MSPS,  
= 0 0.5 MHz,  
Fdata = 491.52 MSPS,  
= I  
F
IN  
F
IN  
F
I
= 250 MHz (Fs/4)  
F
x2 Interpolation  
PLL Off  
-10  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
-90  
PLL Off  
75  
PLL On  
70  
65  
0
61.44  
122.88  
184.32  
245.76  
248.5 249.0 249.5 250.0 250.5 251.0 251.5 252.0 252.5  
f - Frequency - MHz  
f - Frequency - MHz  
Figure 11. Two-Tone IMD Spectral Plot  
Figure 12. Single Carrier W-CDMA Test Model 1  
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TYPICAL CHARACTERISTICS (continued)  
-20  
-20  
-30  
-40  
-50  
Carrier Power: -7.60 dBm,  
Carrier Power: -7.60 dBm,  
ACLR (5 MHz): 77.49 dB,  
ACLR (10 MHz): 82.45 dB,  
Fdata = 245.76 MSPS,  
ACLR (5 MHz): 80.66 dB,  
ACLR (10 MHz): 82.61 dB,  
Fdata = 245.76 MSPS,  
IF = 61.44 MHz,  
-30  
-40  
-50  
-60  
-70  
-80  
-90  
-100  
IF = 61.44 MHz,  
x4 Interpolation  
PLL Off  
x4 Interpolation  
PLL On  
-60  
-70  
-80  
-90  
-100  
-110  
-120  
-110  
-120  
48.9  
53.9  
58.9 63.9  
f - Frequency - MHz  
68.9  
73.9  
48.9  
53.9  
58.9  
63.9  
68.9  
73.9  
f - Frequency - MHz  
Figure 13. Single Carrier W-CDMA Test Model 1  
Figure 14. Single Carrier W-CDMA Test Model 1  
-20  
-30  
-20  
-30  
Carrier Power: -8.66 dBm,  
ACLR (5 MHz): 73.19 dB,  
ACLR (10 MHz): 80.07 dB,  
Fdata = 491.52 MSPS,  
IF = 184.32 MHz,  
Carrier Power: -8.66 dBm,  
ACLR (5 MHz): 68.61 dB,  
ACLR (10 MHz): 75.91 dB,  
Fdata = 491.52 MSPS,  
IF = 184.32 MHz,  
-40  
-50  
-40  
x2 Interpolation  
PLL Off  
x2 Interpolation  
PLL On  
-50  
-60  
-60  
-70  
-70  
-80  
-80  
-90  
-90  
-100  
-100  
-110  
-120  
-110  
-120  
172  
177  
182 187  
f - Frequency - MHz  
192  
197  
172  
177  
182  
187  
192  
197  
f - Frequency - MHz  
Figure 15. Single Carrier W-CDMA Test Model 1  
Figure 16. Single Carrier W-CDMA Test Model 1  
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SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
TYPICAL CHARACTERISTICS (continued)  
-20  
-30  
-40  
-50  
-60  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
-90  
-100  
Carrier Power: -8.99 dBm,  
ACLR (5 MHz): 68.22 dB,  
ACLR (10 MHz): 74.15 dB,  
Fdata = 245.76 MSPS,  
IF = Baseband,  
Carrier Power: -8.99 dBm,  
ACLR (5 MHz): 64.23 dB,  
ACLR (10 MHz): 71.27 dB,  
Fdata = 245.76 MSPS,  
IF = Baseband,  
x4 Interpolation  
CMIX PLL Off  
x4 Interpolation  
CMIX PLL On  
-70  
-80  
-90  
-100  
-110  
-120  
-110  
-120  
233  
238  
243  
248  
253  
258  
233  
238  
243  
248  
253  
258  
f - Frequency - MHz  
f - Frequency - MHz  
Figure 17. Single Carrier W-CDMA Test Model 1  
Figure 18. Single Carrier W-CDMA Test Model 1  
-20  
-30  
-20  
-30  
Carrier Power: -11.98 dBm,  
ACLR (5 MHz): 69.74 dB,  
ACLR (10 MHz): 75.41 dB,  
Fdata = 491.52 MSPS,  
IF = 184.32 MHz,  
Carrier Power: -11.98 dBm,  
ACLR (5 MHz): 66.16 dB,  
ACLR (10 MHz): 72.84 dB,  
Fdata = 491.52 MSPS,  
IF = 184.32 MHz,  
-40  
-50  
-60  
-40  
x2 Interpolation  
PLL Off  
x2 Interpolation  
PLL On  
-50  
-60  
-70  
-80  
-70  
-80  
-90  
-90  
-100  
-110  
-120  
-100  
-110  
-120  
160 165 170 175 180 185 190 195 200 205 210  
f - Frequency - MHz  
160 165 170 175 180 185 190 195 200 205 210  
f - Frequency - MHz  
Figure 19. Two Carrier W-CDMA Test Model 1  
Figure 20. Two Carrier W-CDMA Test Model 1  
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TYPICAL CHARACTERISTICS (continued)  
-20  
-20  
Carrier Power: -15.85 dBm,  
Carrier Power: -15.85 dBm,  
ACLR (5 MHz): 65.85 dB,  
ACLR (10 MHz): 69.60 dB,  
Fdata = 491.52 MSPS,  
IF = 184.32 MHz,  
ACLR (5 MHz): 69.66 dB,  
ACLR (10 MHz): 70.65 dB,  
Fdata = 491.52 MSPS,  
IF = 184.32 MHz,  
-30  
-40  
-50  
-30  
-40  
x2 Interpolation  
PLL Off  
x2 Interpolation  
PLL On  
-50  
-60  
-70  
-80  
-90  
-60  
-70  
-80  
-90  
-100  
-110  
-120  
-100  
-110  
-120  
160 165 170 175 180 185 190 195 200 205 210  
f - Frequency - MHz  
160 165 170 175 180 185 190 195 200 205 210  
f - Frequency - MHz  
Figure 21. Four Carrier W-CDMA Test Model 1  
Figure 22. Four Carrier W-CDMA Test Model 1  
-20  
-20  
Carrier Power: -15.20 dBm,  
ACLR (5 MHz): 71.18 dB,  
ACLR (10 MHz): 72.26 dB,  
Fdata = 491.52 MSPS,  
IF = 184.32 MHz,  
Carrier Power: -15.20 dBm,  
ACLR (5 MHz): 66.53 dB,  
-30 ACLR (10 MHz): 69.68 dB,  
Fdata = 491.52 MSPS,  
-30  
IF = 184.32 MHz,  
x2 Interpolation  
PLL On  
-40  
-50  
-40  
x2 Interpolation  
PLL Off  
-50  
-60  
-60  
-70  
-80  
-90  
-70  
-80  
-90  
-100  
-100  
-110  
-120  
-110  
-120  
160 165 170 175 180 185 190 195 200 205 210  
f - Frequency - MHz  
160 165 170 175 180 185 190 195 200 205 210  
f - Frequency - MHz  
Figure 23. Three Carrier W-CDMA Test Model 1 with Gap  
Figure 24. Three Carrier W-CDMA Test Model 1 with Gap  
TEST METHODOLOGY  
Typical AC specifications were characterized with the DAC5682ZEVM using the test configuration shown in  
Figure 25. A sinusoidal master clock frequency is generated by an HP8665B signal generator and into a splitter.  
One output drives an Agilent 8133A pulse generator, and the other drives the CDCM7005 clock driver. The  
8133A converts the sinusoidal frequency into a square wave output clock and drives an Agilent ParBERT  
81250A pattern-generator clock. On the EVM, the DAC5682Z CLKIN/C input clock is driven by an CDCM7005  
clock distribution chip that is configured to simply buffer the external 8665B clock or divide it down for PLL test  
configurations.  
The DAC5682Z output is characterized with a Rohde and Schwarz FSU spectrum analyzer. For WCDMA signal  
characterization, it is important to use a spectrum analyzer with high IP3 and noise subtraction capability so that  
the spectrum analyzer does not limit the ACPR measurement. For all specifications, both DACA and DACB are  
measured and the lowest value used as the specification.  
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SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
DAC5682ZEVM SMA Adapter Board  
DAC5682Z DAC  
100  
Agilent 81205A  
ParBERT  
3.3 V  
100  
D15  
P
N
3.3 V  
3.3 V  
Rohde &  
Schwartz  
FSU  
Spectrum  
Analyzer  
DAC-A  
DAC-B  
D0  
P
N
3.3 V  
100  
100  
100  
100  
3.3 V  
Pattern  
Memory  
SYNC  
DCLK  
P
N
Swap Cable  
For DAC-B  
measurements  
100  
P
N
3.3 V  
100  
DLL  
opt.  
PLL  
36 each  
SMA-SMA cables  
Loop  
Filter  
CDCM7005  
Opt.  
Clock  
Divider  
100  
Optional  
Divider  
DAC5682ZEVM  
HP8665B  
Synthesized  
Signal  
Agilent 8133A  
Pulse Generator  
Generator  
Figure 25. DAC5682Z Test Configuration for Normal Clock Mode  
DEFINITION OF SPECIFICATIONS  
Adjacent Carrier Leakage Ratio (ACLR): Defined for a 3.84Mcps 3GPP W-CDMA input signal measured in a  
3.84MHz bandwidth at a 5MHz offset from the carrier with a 12dB peak-to-average ratio.  
Analog and Digital Power Supply Rejection Ratio (APSSR, DPSSR): Defined as the percentage error in the  
ratio of the delta IOUT and delta supply voltage normalized with respect to the ideal IOUT current.  
Differential Nonlinearity (DNL): Defined as the variation in analog output associated with an ideal 1 LSB  
change in the digital input code.  
Gain Drift: Defined as the maximum change in gain, in terms of ppm of full-scale range (FSR) per °C, from the  
value at ambient (25°C) to values over the full operating temperature range.  
Gain Error: Defined as the percentage error (in FSR%) for the ratio between the measured full-scale output  
current and the ideal full-scale output current.  
Integral Nonlinearity (INL): Defined as the maximum deviation of the actual analog output from the ideal output,  
determined by a straight line drawn from zero scale to full scale.  
Intermodulation Distortion (IMD3, IMD): The two-tone IMD3 or four-tone IMD is defined as the ratio (in dBc) of  
the worst 3rd-order (or higher) intermodulation distortion product to either fundamental output tone.  
Offset Drift: Defined as the maximum change in DC offset, in terms of ppm of full-scale range (FSR) per °C,  
from the value at ambient (25°C) to values over the full operating temperature range.  
Offset Error: Defined as the percentage error (in FSR%) for the ratio of the differential output current  
(IOUT1–IOUT2) and the mid-scale output current.  
Output Compliance Range: Defined as the minimum and maximum allowable voltage at the output of the  
current-output DAC. Exceeding this limit may result reduced reliability of the device or adversely affecting  
distortion performance.  
Reference Voltage Drift: Defined as the maximum change of the reference voltage in ppm per degree Celsius  
from value at ambient (25°C) to values over the full operating temperature range.  
Spurious Free Dynamic Range (SFDR): Defined as the difference (in dBc) between the peak amplitude of the  
output signal and the peak spurious signal.  
18  
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Signal to Noise Ratio (SNR): Defined as the ratio of the RMS value of the fundamental output signal to the  
RMS sum of all other spectral components below the Nyquist frequency, including noise, but excluding the first  
six harmonics and dc.  
TYPICAL APPLICATION SCHEMATIC  
(1) Power supply decoupling capacitors not shown.  
(2) Internal Reference configuration shown.  
Figure 26. Schematic  
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DETAILED DESCRIPTION  
The primary modes of operation, listed in Table 1, are selected by registers CONFIG1, CONFIG2 and CONFIG3.  
Table 1. DAC5682Z Modes of Operation  
LVDS  
Input  
Data  
Max Total  
Input Bus  
Rate  
No. of  
FIR0,  
FIR1,  
Max DCLK  
Max CLKIN Freq [DDR]  
Max Input Data  
Rate Per Chan  
(#Ch @ MSPS)  
Max Signal  
Mode  
Name  
DACs Interp. CMIX0 CMIX1  
Out  
Device  
Config.  
BW Per DAC  
(2)  
Factor Mode  
Mode  
Mode  
Freq (MHz)(1)  
(MHz)  
(MSPS)  
(MHz)  
1X1  
1
X1  
Single Real  
A
1000  
500  
1000  
1 at 1000  
500  
(Bypass)  
1X2  
1
1
1
1
1
1
2
2
2
2
X2  
X2  
X4  
X4  
X4  
X4  
X1  
X2  
X2  
X2  
LP  
HP  
LP  
HP  
LP  
HP  
Single Real  
Single Real  
Single Real  
Single Real  
Single Real  
Single Real  
Dual Real  
Dual Real  
Dual Real  
Complex  
A
A
1000  
1000  
1000  
1000  
1000  
1000  
500  
250  
250  
125  
125  
125  
125  
500  
500  
500  
500  
500  
500  
1 at 500  
1 at 500  
1 at 250  
1 at 250  
1 at 250  
1 at 250  
2 at 500  
2 at 500  
2 at 500  
2 at 500  
200  
200  
100  
100  
50  
1X2 HP  
1X4  
LP  
LP  
HP  
HP  
A
250  
1X4 LP/HP  
1X4 HP/LP  
1X4 HP/HP  
2X1  
A
250  
A
250  
A
250  
50  
A/B  
A/B  
A/B  
A/B  
1000  
1000  
1000  
1000  
250  
200  
200  
200  
2X2  
LP  
HP  
1000  
1000  
1000  
2X2 HP  
2X2 CMIX  
LP,  
Fs/4  
2X4  
2
2
2
X4  
X4  
X4  
LP  
LP  
LP  
LP  
Dual Real  
Dual Real  
Complex  
A/B  
A/B  
A/B  
1000  
1000  
1000  
250  
250  
250  
500  
500  
500  
2 at 250  
2 at 250  
2 at 250  
100  
100  
100  
2X4 LP/HP  
2X4 CMIX  
HP  
LP,  
Fs/4  
2X4 HP/LP  
2X4 HP/HP  
2
2
X4  
X4  
HP  
HP  
LP  
Dual Real  
Dual Real  
A/B  
A/B  
1000  
1000  
250  
250  
500  
500  
2 at 250  
2 at 250  
50  
50  
HP  
(1) Also the final DAC sample rate in MSPS.  
(2) Assumes a 40% passband for FIR0 and/or FIR1 filters in all modes except 1X1 and 2X1 where simple Nyquist frequency is listed.  
Slightly wider bandwidths may be achievable depending on filtering requirements. Refer to FIR Filters section for more detail on filter  
characteristics. Also refer to Table 7 for IF placement and upconversion considerations.  
Table 2. Register Map  
(MSB)  
Bit 7  
(LSB)  
Bit 0  
Name  
Address  
Default  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
STATUS0  
CONFIG1  
CONFIG2  
0x00  
0x01  
0x02  
0x03  
0x10  
0xC0  
PLL_lock  
DLL_lock  
Unused  
Unused  
FIR2x4x  
device_ID(2:0)  
SLFTST _ena  
version(1:0)  
FIFO_offset(2:0)  
CMIX0_mode(1:0)  
DAC_delay(1:0)  
fir_ena  
Twos_ comp  
DAC_offset _ena  
Unused  
dual_DAC  
Unused  
CMIX1_mode(1:0)  
SLFTST_err  
_mask  
Pattern_err  
_mask  
CONFIG3  
STATUS4  
CONFIG5  
0x03  
0x04  
0x05  
0x70  
0x00  
0x00  
FIFO_err_ mask  
FIFO_err  
SwapAB_ out  
Unused  
B_equals _A  
Unused  
SW_sync  
SW_sync _sel  
Unused  
SLFTST_err  
rev_bus  
Pattern_ err  
Unused  
FIFO_  
sync_dis  
PLL_  
bypass  
SIF4  
clkdiv_ sync_dis  
Sleep_B  
Reserved  
BiasLPF_A  
DLL_ bypass  
BiasLPF_B  
Reserved  
CONFIG6  
CONFIG7  
CONFIG8  
CONFIG9  
CONFIG10  
CONFIG11  
CONFIG12  
CONFIG13  
CONFIG14  
CONFIG15  
0x06  
0x07  
0x08  
0x09  
0x0A  
0x0B  
0x0C  
0x0D  
0x0E  
0x0F  
0x0C  
0xFF  
0x00  
0x00  
0x00  
0x00  
0x00  
0x00  
0x00  
0x00  
Hold_sync _dis  
Unused  
Sleep_A  
PLL_ sleep  
DLL_ sleep  
DACA_gain(3:0)  
DACB_gain(3:0)  
DLL_ restart  
Reserved  
Reserved  
PLL_m(4:0)  
PLL_n(2:0)  
DLL_delay(3:0)  
VCO_div2  
DLL_invclk  
DLL_ifixed(2:0)  
PLL_LPF _reset  
PLL_gain(1:0)  
Offset_sync  
PLL_range(3:0)  
Reserved(1:0)  
OffsetA(12:8)  
OffsetA(7:0)  
SDO_func_sel(2:0)  
OffsetB(12:8)  
OffsetB(7:0)  
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Register name: STATUS0 – Address: 0x00, Default = 0x03  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
0
Bit 1  
1
Bit 0  
1
PLL_lock  
0
DLL_lock  
0
Unused  
0
device_ID(2:0)  
0
version(1:0)  
0
PLL_lock:  
DLL_lock:  
Asserted when the internal PLL is locked. (Read Only)  
Asserted when the internal DLL is locked. Once the DLL is locked, this bit should remain a  
‘1’ unless the DCLK input clock is removed or abruptly changes frequency causing the DLL  
to fall out of lock. (Read Only)  
device_ID(2:0): Returns ‘000’ for DAC5682Z Device_ID code. (ReadOnly)  
version(1:0): A hardwired register that contains the register set version of the chip. (ReadOnly)  
version (1:0)  
Identification  
‘01’  
‘10’  
‘11'  
PG1.0 Initial Register Set  
PG1.1 Register Set  
Production Register Set  
Register name: CONFIG1 – Address: 0x01, Default = 0x10  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
0
Bit 1  
Bit 0  
0
DAC_delay(1:0)  
Unused  
0
FIR_ena  
1
SLFTST_ena  
0
FIFO_offset(2:0)  
0
0
0
DAC_delay(1:0): DAC data delay adjustment. (0–3 periods of the DAC clock) This can be used to adjust  
system level output timing. The same delay is applied to both DACA and DACB data paths.  
FIR_ena:  
When set, the interpolation filters are enabled.  
SLFTST_ena:  
When set, a Digital Self Test (SLFTST) of the core logic is enabled. Refer to Digital Self  
Test Mode section for details on SLFTST operation.  
FIFO_offset(2:0): Programs the FIFO’s output pointer location, allowing the input pointer to be shifted –4 to  
+3 positions upon SYNC. Default offset is 0 and is updated upon each sync event – unless  
disabled via FIFO_sync_dis in CONFIG5 register.  
FIFO_offset(2:0)  
Offset  
+3  
011  
010  
001  
000  
111  
110  
101  
100  
+2  
+1  
0
–1  
–2  
–3  
–4  
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Register name: CONFIG2 – Address: 0x02, Default = 0xC0  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
0
Bit 1  
0
Bit 0  
Twos_comp  
1
dual_DAC  
1
FIR2x4x  
0
Unused  
0
CMIX1_mode(1:0)  
CMIX0_mode(1:0)  
0
0
Twos_comp:  
dual_DAC:  
When set (default) the input data format is expected to be 2’s complement, otherwise  
offset binary format is expected.  
Selects between dual DAC mode (default) and single DAC mode. This bit is also used  
to select input interleaved data.  
FIR2x4x:  
When set, 4X interpolation of the input data is performed, otherwise 2X interpolation.  
CMIX1_mode(1:0):  
Determines the mode of FIR1 and final CMIX1 blocks. Settings apply to both A and B  
channels. Refer to Table 9 for a detailed description of CMIX1 modes.  
Mode  
CMIX1_mode(1) CMIX1_mode(0)  
Normal (Low  
Pass)  
0
0
High Pass  
+FDAC /4  
–FDAC/4  
0
1
1
1
0
1
CMIX0_mode(1:0): Determines the mode of FIR0 and CMIX0 blocks. Since CMIX0 is located between FIR0  
and FIR1, its output is half-rate. Refer to Table 8 for a detailed description of CMIX0  
modes. The table below shows the effective Fs/4 or ±Fs/8 mixing with respect to the final  
DAC sample rate. Settings apply to both A and B channels.  
Mode  
CMIX1_mode(1) CMIX1_mode(0)  
Normal (Low  
Pass)  
0
0
High Pass  
+FDAC /8  
–FDAC/8  
0
1
1
1
0
1
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Register name: CONFIG3 – Address: 0x03, Default = 0x70  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
Bit 0  
DAC_offset  
_ena  
SLFTST_err  
_mask  
FIFO_err_  
mask  
Pattern_err_  
mask  
SwapAB_out  
B_equals_A  
SW_sync  
SW_sync_sel  
0
1
1
1
0
0
0
0
DAC_offset_ena:  
When set, the values of OffsetA(12:0) and OffsetB(12:0) in CONFIG12 through  
CONFIG15 registers are summed into the DAC-A and DAC-B data paths. This provides  
a system-level offset adjustment capability that is independent of the input data.  
SLFTST_err_mask: When set, masks out the SLFTST_err bit in STATUS4 register. Refer to Digital Self  
Test Mode section for details on SLFTST operation.  
FIFO_err_mask:  
Pattern_err_mask:  
SwapAB_out:  
When set, masks out the FIFO_err bit in STATUS4 register.  
When set, masks out the Pattern err bit in STATUS4 register.  
When set, the A/B data paths are swapped prior to routing to the DAC-A and DAC-B  
outputs.  
B_equals_A:  
When set, the data routed to DAC-A is also routed to DAC-B. This allows wire OR’ing of  
the two DAC outputs together at the board level to create a 2X drive strength single  
DAC output.  
SW_sync:  
This bit can be used as a substitute for the LVDS external SYNC input pins for both  
synchronization and transmit enable control.  
SW_sync_sel:  
When set, the SW_sync bit is used as the only synchronization input and the LVDS  
external SYNC input pins are ignored.  
Register name: STATUS4 – Address: 0x04, Default = 0x00  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
Bit 0  
Unused  
0
SLFTST_err  
0
FIFO_err  
0
Pattern_err  
0
Unused  
0
Unused  
0
Unused  
0
Unused  
0
SLFTST_err:  
Asserted when the Digital Self Test (SLFTST) fails. To clear the error, write a ‘0’ to this  
register bit. This bit is also output on the SDO pin when the Self Test is enabled via  
SLFTST_ena control bit in CONFIG1. Refer to Digital Self Test Mode section for details on  
SLFTST operation.  
FIFO_err:  
Asserted when the FIFO pointers over run each other causing a sample to be missed. To  
clear the error, write a ‘0’ to this register bit.  
Pattern_err:  
A digital checkerboard pattern compare function is provided for board level confidence  
testing and DLL limit checks. If the Pattern_err_mask bit via CONFIG3 is cleared, logic is  
enabled to continuously monitor input FIFO data. Any received data pattern other than  
0xAAAA or 0x5555 causes this bit to be set. To clear the error, flush out the previous  
pattern error by inputting at least 8 samples of the 0xAAAA and/or 0x5555, then write a ‘0’  
to this register bit.  
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Register name: CONFIG5 – Address: 0x05, Default = 0x00  
Bit 7  
SIF4  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
Bit 0  
rev_bus  
clkdiv_sync  
_dis  
FIFO_sync _dis  
Reserved  
DLL_bypass  
PLL_bypass  
Reserved  
0
0
0
0
0
0
0
0
SIF4:  
When set, the serial interface is in 4 pin mode, otherwise it is in 3 pin mode. Refer to  
SDO_func_sel(2:0) bits in CONFIG14 register for options available to output status  
indicator data on the SDO pin.  
rev_bus:  
Reverses the LVDS input data bus so that the MSB to LSB order is swapped. This  
function is provided to ease board level layout and avoid wire crossovers in case the  
LVDS data source output bus is mirrored with respect to the DAC’s input data bus.  
clkdiv_sync_dis:  
FIFO_sync_dis:  
Disables the clock divider sync when this bit is set.  
Disables the FIFO offset sync when this bit is set. See FIFO_offset(2:0) bits in CONFIG1  
register  
Reserved (Bit 3):  
DLL_bypass:  
Set to 0 for proper operation.  
When set, the DLL is bypassed and the LVDS data source is responsible for providing  
correct setup and hold timing.  
PLL_bypass:  
When set, the PLL is bypassed.  
Set to 0 for proper operation.  
Reserved (Bit 0):  
Register name: CONFIG6 – Address: 0x06, Default = 0x0C  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
Bit 0  
Hold_sync _dis  
0
Unused  
0
Sleep_B  
0
Sleep_A  
0
BiasLPF_A  
1
BiasLPF_B  
1
PLL_sleep  
0
DLL_sleep  
0
Hold_sync_dis: When set, disables the sync to the FIFO output HOLD block. Typically this bit should be  
cleared to ‘0’ for normal operation and also follow the same value as the FIFO_sync_dis  
control bit in CONFIG5.  
Sleep_B:  
When set, DACB is put into sleep mode. DACB is not automatically set into sleep mode  
when configured for single DAC mode via dual_DAC bit in CONFIG2. Set this Sleep_B bit  
for the lowest power configuration in single DAC mode since output is on DACA only.  
Sleep_A:  
When set, DACA is put into sleep mode.  
BiasLPF_A:  
Enables a 95 kHz low pass filter corner on the DACA current source bias when set. If this bit  
is cleared, a 472 Hz filter corner is used.  
BiasLPF_B:  
Enables a 95 kHz low pass filter corner on the DACB current source bias when set. If this bit  
is cleared, a 472 Hz filter corner is used.  
PLL_sleep:  
DLL_sleep:  
When set, the PLL is put into sleep mode.  
When set, the DLL is put into sleep mode.  
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Register name: CONFIG7 – Address: 0x07, Default = 0xFF  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
1
Bit 2  
Bit 1  
1
Bit 0  
1
DACA_gain(3:0)  
DACB_gain(3:0)  
1
1
1
1
1
DACA_gain(3:0):  
Scales DACA output current in 16 equal steps.  
VEXTIO  
x DACA_gain + 1  
(
)
R
bias  
DACB_gain(3:0):  
Same as above except for DACB.  
Register name: CONFIG8 – Address: 0x08, Default = 0x00  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
0
Bit 2  
Bit 1  
0
Bit 0  
0
Reserved  
0
DLL_restart  
0
Reserved  
0
0
0
Reserved (7:3): Set to ‘00000’ for proper operation.  
DLL_restart:  
This bit is used to restart the DLL. When this bit is set, the internal DLL loop filter is reset to  
zero volts, and the DLL delay line is held at the center of its bias range. When cleared, the  
DLL will acquire lock to the DCLK signal. A DLL restart is accomplished by setting this bit  
with a serial interface write, and then clearing this bit with another serial interface write. Any  
interruption in the DCLK signal or changes to the DLL programming in the CONFIG10  
register must be followed by this DLL restart sequence. Also, when this bit is set, the  
DLL_lock indicator in the STATUS0 register is cleared.  
Reserved (1:0): Set to ‘00’ for proper operation  
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Register name: CONFIG9 – Address: 0x09, Default = 0x00  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
0
Bit 2  
0
Bit 1  
Bit 0  
0
PLL_m(4:0)  
0
PLL_n(2:0)  
0
0
0
0
PLL_m: M portion of the M/N divider of the PLL thermometer encoded:  
PLL_m(4:0)  
00000  
M value  
1
00001  
2
4
00011  
00111  
8
01111  
16  
11111  
32  
All other values  
Invalid  
PLL_n: N portion of the M/N divider of the PLL thermometer encoded. If supplying a high rate CLKIN  
frequency, the PLL_n value should be used to divide down the input CLKIN to maintain a maximum  
PFD operating of 160 MHz.  
PLL_n(2:0)  
N value  
000  
001  
1
2
011  
4
8
111  
All other values  
Invalid  
PLL Function:  
é
ù
M
ê( )ú  
f
=
x f  
ref  
vco  
N
êë ( )úû  
where ƒref is the frequency of the external DAC clock input on the CLKIN/CLKINC pins.  
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Register name: CONFIG10 – Address: 0x0A, Default = 0x00  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
0
Bit 1  
Bit 0  
0
DLL_delay(3:0)  
DLL_invclk  
0
DLL_ifixed(2:0)  
0
0
0
0
0
DLL_delay(3:0):  
The DCLKP/N LVDS input data clock has a DLL to automatically skew the clock to LVDS  
data timing relationship, providing proper setup and hold times. DLL_delay(3:0) is used to  
manually adjust the DLL delay ± from the fixed delay set by DLL_ifixed(2:0). Adjustment  
amounts are approximate.  
DLL_delay(3:0)  
1000  
Delay Adjust (degrees)  
50°  
55°  
1001  
1010  
60°  
1011  
65°  
1100  
70°  
1101  
75°  
1110  
80°  
1111  
85°  
0000  
90° (Default)  
95°  
0001  
0010  
100°  
105°  
110°  
115°  
120°  
125°  
0011  
0100  
0101  
0110  
0111  
DLL_invclk:  
When set, used to invert an internal DLL clock to force convergence to a different solution.  
This can be used in the case where the DLL delay adjustment has exceeded the limits of  
its range.  
DLL_ifixed(2:0):  
Adjusts the DLL delay line bias current. Refer to the Electrical Characteristics table. Used  
in conjunction with the DLL_invclk bit to select appropriate delay range for a given DCLK  
frequency:  
'011' – maximum bias current and minimum delay range  
'000' – mid scale bias current  
'101' – minimum bias current and maximum delay range  
'100' – do not use.  
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Register name: CONFIG11 – Address: 0x0B, Default = 0x00  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
0
Bit 0  
0
PLL_LPF_ reset  
0
VCO_div2  
0
PLL_gain(1:0)  
PLL_range(3:0)  
0
0
0
0
PLL_LPF_reset: When a logic high, the PLL loop filter (LPF) is pulled down to 0V. Toggle from ‘1’ to ‘0’ to  
restart the PLL if an over-speed lock-up occurs. Over-speed can happen when the process  
is fast, the supplies are higher than nominal, etc., resulting in the feedback dividers missing  
a clock.  
VCO_div2:  
When set, the PLL CLOCK output is 1/2 the PLL VCO frequency. Used to run the VCO at  
2X the needed clock frequency to reduce phase noise for lower input clock rates.  
PLL_gain(1:0):  
Used to adjust the PLL’s Voltage Controlled Oscillator (VCO) gain, KVCO. Refer to the  
Electrical Characteristics table. By increasing the PLL_gain, the VCO can cover a broader  
range of frequencies; however, the higher gain also increases the phase noise of the PLL.  
In general, lower PLL_gain settings result in lower phase noise. The KVCO of the VCO can  
also affect the PLL stability and is used to determine the loop filter components. See  
section on determining the PLL filter components for more detail.  
PLL_range(3:0): Programs the PLL VCO fixed bias current. Refer to the Electrical Characteristics table. This  
setting, in conjunction with the PLL_gain(1:0), sets the achievable frequency range of the  
PLL VCO:  
'000' – minimum bias current and lowest VCO frequency range  
'111' – maximum bias current and highest VCO frequency range  
Register name: CONFIG12 – Address: 0x0C, Default = 0x00  
Bit 7  
Reserved(1:0)  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
0
Bit 0  
0
Offset_sync  
0
OffsetA(12:8)  
0
0
0
0
0
Reserved(1:0):  
Offset_sync:  
Set to ‘00’ for proper operation.  
On a change from ‘0’ to ‘1’ the values of the OffsetA(12:0) and OffsetB(12:0) control  
registers are transferred to the registers used in the DAC-A and DAC-B offset calculations.  
This double buffering allows complete control by the user as to when the change in the  
offset value occurs. This bit does not auto-clear. Prior to updating new offset values, it is  
recommended that the user clear this bit.  
OffsetA(12:8):  
Upper 5 bits of the offset adjustment value for the A data path. (SYNCED via Offset_sync)  
Register name: CONFIG13 – Address: 0x0D, Default = 0x00  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
0
Bit 1  
0
Bit 0  
0
OffsetA(7:0)  
0
0
0
0
0
OffsetA(7:0):  
Lower 8 bits of the offset adjustment value for the A data path. (SYNCED via Offset_sync)  
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Register name: CONFIG14 – Address: 0x0E, Default = 0x00  
Bit 7  
Bit 6  
Bit 5  
Bit 4  
Bit 3  
Bit 2  
Bit 1  
0
Bit 0  
0
SDO_func_sel(2:0)  
0
OffsetB(12:8)  
0
0
0
0
0
SDO_func_sel(2:0): Selects the signal for output on the SDO pin. When using the 3 pin serial interface  
mode, this allows the user to multiplex several status indicators onto the SDO pin. In 4  
pin serial interface mode, programming this register to view one of the 5 available status  
indicators will override normal SDO serial interface operation.  
SDO_func_sel  
(2:0)  
Output to SDO  
000, 110, 111  
Normal SDO function  
PLL_lock  
001  
010  
011  
100  
101  
DLL_lock  
Pattern_err  
FIFO_err  
SLFTST_err  
OffsetB(12:8):  
Upper 5 bits of the offset adjustment value for the B data path. (SYNCED via Offset_sync)  
Register name: CONFIG15 – Address: 0x0F, Default = 0x00  
Bit 7  
0
Bit 6  
0
Bit 5  
0
Bit 4  
0
Bit 3  
0
Bit 2  
0
Bit 1  
0
Bit 0  
0
OffsetB(7:0)  
OffsetB(7:0): Lower 8 bits of the offset adjustment value for the B data path. (SYNCED via Offset_sync)  
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SERIAL INTERFACE  
The serial port of the DAC5682Z is a flexible serial interface which communicates with industry standard  
microprocessors and microcontrollers. The interface provides read/write access to all registers used to define the  
operating modes of DAC5682Z. It is compatible with most synchronous transfer formats and can be configured  
as a 3 or 4 pin interface by SIF4 in register CONFIG5. In both configurations, SCLK is the serial interface input  
clock and SDENB is serial interface enable. For 3 pin configuration, SDIO is a bidirectional pin for both data in  
and data out. For 4 pin configuration, SDIO is data in only and SDO is data out only.  
Each read/write operation is framed by signal SDENB (Serial Data Enable Bar) asserted low for 2 to 5 bytes,  
depending on the data length to be transferred (1–4 bytes). The first frame byte is the instruction cycle which  
identifies the following data transfer cycle as read or write, how many bytes to transfer, and what address to  
transfer the data. Table 3 indicates the function of each bit in the instruction cycle and is followed by a detailed  
description of each bit. Frame bytes 2 to 5 comprise the data transfer cycle.  
Table 3. Instruction Byte of the Serial Interface  
MSB  
LSB  
Bit  
7
6
5
4
3
2
1
0
Description  
R/W  
N1  
N0  
A4  
A3  
A2  
A1  
A0  
R/W  
[N1 : N0]  
Identifies the following data transfer cycle as a read or write operation. A high indicates a read  
operation from DAC5682Z and a low indicates a write operation to DAC5682Z.  
Identifies the number of data bytes to be transferred per Table 5 below. Data is transferred MSB  
first.  
Table 4. Number of Transferred Bytes Within One  
Communication Frame  
N1  
0
N0  
0
Description  
Transfer 1 Byte  
Transfer 2 Bytes  
Transfer 3 Bytes  
Transfer 4 Bytes  
0
1
1
0
1
1
[A4 : A0]  
Identifies the address of the register to be accessed during the read or write operation. For  
multi-byte transfers, this address is the starting address. Note that the address is written to the  
DAC5682Z MSB first and counts down for each byte.  
Figure 27 shows the serial interface timing diagram for a DAC5682Z write operation. SCLK is the serial interface  
clock input to DAC5682Z. Serial data enable SDENB is an active low input to DAC5682Z. SDIO is serial data in.  
Input data to DAC5682Z is clocked on the rising edges of SCLK.  
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Instruction Cycle  
Data Transfer Cycle (s)  
SDENB  
SCLK  
SDIO  
r/w N1 N0 A4 A3 A2 A1 A0 D7 D6 D5 D4 D3 D2 D1 D0  
t
(SDENB)  
t
S
SCLK  
SDENB  
SCLK  
SDIO  
t
SCLKL  
t
(SDIO)  
h
t
SCLKH  
t
(SDIO)  
S
Figure 27. Serial Interface Write Timing Diagram  
Figure 28 shows the serial interface timing diagram for a DAC5682Z read operation. SCLK is the serial interface  
clock input to DAC5682Z. Serial data enable SDENB is an active low input to DAC5682Z. SDIO is serial data in  
during the instruction cycle. In 3 pin configuration, SDIO is data out from DAC5682Z during the data transfer  
cycle(s), while SDO is in a high-impedance state. In 4 pin configuration, SDO is data out from DAC5682Z during  
the data transfer cycle(s). At the end of the data transfer, SDO will output low on the final falling edge of SCLK  
until the rising edge of SDENB when it will 3-state.  
Instruction Cycle  
Data Transfer Cycle(s)  
SDENB  
SCLK  
SDIO  
SDO  
r/w N1 N0  
-
A3 A2 A1 A0 D7 D6 D5 D4 D3 D2 D1 D0  
D7 D6 D5 D4 D3 D2 D1 D0  
0
0
3 pin Configuration Output  
4 pin Configuration Output  
SDENB  
SCLK  
SDIO  
SDO  
Data n  
Data n-1  
t
(Data)  
d
Figure 28. Serial Interface Read Timing Diagram  
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FIR FILTERS  
Figure 29 shows the magnitude spectrum response for the identical 47-tap FIR0 and FIR1 filters. The transition  
band is from 0.4 to 0.6 × FIN (the input data rate for the FIR filter) with <0.002 dB of pass-band ripple and  
approximately 76dB of stop-band attenuation. Figure 30 shows the region from 0.35 to 0.45 × FIN – up to 0.44x  
FIN there is less than 0.4 dB attenuation. The composite spectrum for x4 interpolation mode, the cascaded  
response of FIR0 and FIR1, is shown in Figure 31. The filter taps for both FIR0 and FIR1 are listed in Table 5.  
Figure 29. Magnitude Spectrum for FIR0 and FIR1  
Figure 30. FIR0 and FIR1 Transition Band  
Figure 31. Magnitude Composite Spectrum for 4x Interpolation Mode  
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Table 5. FIR0 and FIR1 Digital Filter Taps  
TAP#  
1, 47  
COEFF  
–5  
TAP#  
2, 46  
4, 44  
6, 42  
8, 40  
10, 38  
12, 36  
14, 34  
16, 32  
18, 30  
20, 28  
22, 26  
COEFF  
0
0
3, 45  
18  
5, 43  
–42  
0
7, 41  
85  
0
9, 39  
–158  
272  
0
11, 37  
13, 35  
15, 33  
17, 31  
19, 29  
21, 27  
23, 25  
24  
0
–444  
704  
0
0
–1106  
1795  
–3295  
10368  
16384  
0
0
0
DUAL-CHANNEL REAL UPCONVERSION  
The DAC5682Z can be used in a dual channel mode with real upconversion by mixing with a 1, –1, … sequence  
in the signal chain to invert the spectrum. This mixing mode maintains isolation of the A and B channels. The two  
points of mixing, CMIX0 and CMIX1, follow each FIR filter. The mixing modes for each CMIX block is control by  
CMIX0_mode(1:0) and CMIX1(1:0) in register CONFIG2. The wide bandwidths of both FIR0 and FIR1 (40%  
passband) provide options for setting four different frequency ranges, listed in Table 6. With the High Pass/Low  
Pass (2X2 HP/LP mode) and Low Pass/High Pass (2X2 LP/HP mode) settings, the unconverted signal is  
spectrally inverted.  
Table 6. Dual-Channel Real Upconversion Options  
FIR0,  
CMIX0  
MODE  
FIR1,  
CMIX1  
MODE  
INTERP.  
FACTOR  
INPUT  
OUTPUT  
SIGNAL  
SPECTRUM  
INVERTED?  
MODE NAME  
FREQUENCY(1)  
FREQUENCY(1)  
BANDWIDTH(1)  
2X4  
X4  
X4  
X4  
X4  
LP  
HP  
HP  
LP  
LP  
LP  
HP  
HP  
0.0 to 0.4 × fDATA  
0.0 to 0.4 × fDATA  
0.0 to 0.4 × fDATA  
0.0 to 0.4 × fDATA  
0.0 to 0.4 × fDATA  
0.6 to 0.8 × fDATA  
1.2 to 1.4 × fDATA  
1.6 to 2.0 × fDATA  
0.4 × fDATA  
0.2 × fDATA  
0.2 × fDATA  
0.4 × fDATA  
No  
Yes  
No  
2X4 HP/LP  
2X4 HP/HP  
2X4 LP/HP  
Yes  
(1) fDATAis the input data rate of each channel after de-interleaving.  
COARSE MIXERS: CMIX0 AND CMIX1  
The DAC5682Z has two coarse mixer (CMIX) blocks: CMIX0 follows FIR0 and CMIX1 follows FIR1. (See  
Figure 32) Each CMIX block provides mixing capability of fixed frequencies Fs/2 (real) or ±Fs/4 (complex) with  
respect to the output frequency of the preceding FIR block. Since FIR0 and CMIX0 are only used in x4  
interpolation modes, the output is half-rate relative to the DAC output frequency. Therefore, an ±Fs/4 mixing  
sequence results in ±FDAC/8 frequency shift at the DAC output.  
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Table 7. CMIX0 Mixer Sequences  
CMIX0_mode(0)  
Mode  
CMIX0_mode(1)  
MIXING SEQUENCE  
Normal  
(Low Pass, No Mixing)  
0
0
1
1
0
1
0
1
FIR0A = { +A, +A , +A, +A }  
FIR0B = { +B, +B , +B, +B }  
High Pass  
FIR0A = { +A, –A , +A, –A }  
FIR0B = { +B, –B , +B, –B }  
+FDAC /8 (+Fs/4)  
–FDAC /8 (–Fs/4)  
FIR0A = { +A, –B , –A, +B }  
FIR0B = { +B, +A , –B, –A }  
FIR0A = { +A, +B , –A, –B }  
FIR0B = { +B, –A , –B, +A }  
Table 8. CMIX1 Mixer Sequences  
Mode  
CMIX1_mode(1)  
CMIX1_mode(0)  
MIXING SEQUENCE  
Normal  
(Low Pass, No Mixing)  
0
0
1
1
0
DACA = { +A, +A , +A, +A }  
DACB = { +B, +B , +B, +B }  
High Pass (Fs/2)  
1
0
1
DACA = { +A, –A , +A, –A }  
DACB = { +B, –B , +B, –B }  
+FDAC /4  
DACA = { +A, –B , –A, +B }  
DACB = { +B, +A , –B, –A }  
–FDAC /4  
DACA = { +A, +B , –A, –B }  
DACB = { +B, –A , –B, +A }  
A Data In  
x2  
x2  
A Data Out  
FIR1  
FIR0  
B Data In  
x2  
x2  
B Data Out  
Block Diagram  
(same for each)  
0
1
A Mix In  
A Mix Out  
0
1
1
-1  
1
B Mix Out  
B Mix In  
0
0
1
1
-1  
CMIXx_mode(1:0)  
Mix Sequencer  
Figure 32. CMIX0 and CMIX1 Coarse Mixers Block Diagram  
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CLOCK AND DATA MODES  
There are two modes of operation to drive the internal clocks on the DAC5682Z. Timing diagrams for both  
modes are shown in Figure 33. EXTERNAL CLOCK MODE accepts an external full-rate clock input on the  
CLKIN/CLKINC pins to drive the DACs and final logic stages while distributing an internally divided down clock  
for lower speed logic such as the interpolating FIRs. PLL CLOCK MODE uses an internal clock multiplying PLL  
to derive the full-rate clock from an external lower rate reference frequency on the CLKIN/CLKINC pins. In both  
modes, an LVDS half-rate data clock (DCLKP/DCLKN) is provided by the user and is typically generated by a  
toggling data bit to maintain LVDS data to DCLK timing alignment. LVDS data relative to DCLK is input using  
Double Data Rate (DDR) switching using both rising and falling edges as shown in the both figures below. The  
CONFIG10 register contains user controlled settings for the DLL to adjust for the DCLK input frequency and  
various tSKEW timing offsets between the LVDS data and DCLK. The CDCM7005 from Texas Instruments is  
recommended for providing phase aligned clocks at different frequencies for device-to-device clock distribution  
and multiple DAC synchronization.  
CLKINC  
PLL = 4X  
CLKIN  
Two Clock Mode Shown: PLL = 4X and EXTERNAL (PLL = OFF)  
CLKIN  
EXTERNAL  
CLKINC  
DACCLK  
(Internal)  
DCLKN  
DCLKP  
t
t
SKEW(B)  
SKEW(A)  
t
S
t
Valid Data (A)  
Valid Data (B)  
H
SYNCN  
Transmit Enable / Synchronization Event  
SYNCP  
D[15:0]N  
D[15:0]P  
A
B
A
B
A
A
A
A
A
A
N+1  
Single DAC Mode (1X1)  
Dual DAC Mode (2X2)  
1
3
0
2
N
A
B
N-2  
0
1
0
1
N-2  
Figure 33. Clock and Data Timing Diagram  
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PLL CLOCK MODE  
In PLL Clock Mode, the user provides an external reference clock to the CLKIN/C input pins. Refer to Figure 34.  
An internal clock multiplying PLL uses the lower-rate reference clock to generate a high-rate clock for the DAC.  
This function is very useful when a high-rate clock is not already available at the system level; however, the  
internal VCO phase noise in PLL Clock Mode may degrade the quality of the DAC output signal when compared  
to an external low jitter clock source.  
The internal PLL has a type four phase-frequency detector (PFD) comparing the CLKIN/C reference clock with a  
feedback clock to drive a charge pump controlling the VCO operating voltage and maintaining synchronization  
between the two clocks. An external low-pass filter is required to control the loop response of the PLL. See the  
Low-Pass Filter section for the filter setting calculations. This is the only mode where the LPF filter applies.  
The input reference clock N-Divider is selected by CONFIG9 PLL_n(2:0) for values of ÷1, ÷2, ÷4 or ÷8. The VCO  
feedback clock M-Divider is selected by CONFIG9 PLL_m(4:0) for values of ÷1, ÷2, ÷4, ÷8, ÷16 or ÷32. The  
combination of M-Divider and N-Divider form the clock multiplying ratio of M/N. If the reference clock frequency is  
greater than 160 MHz, use a N-Divider of ÷2, ÷4 or ÷8 to avoid exceeding the maximum PFD operating  
frequency.  
For DAC sample rates less than 500MHz, the phase noise of DAC clock signal can be improved by programming  
the PLL for twice the desired DAC clock frequency, and setting the CONFIG11 VCO_div2 bit. If not using the  
PLL, set CONFIG5 PLL_bypass and CONFIG6 PLL_sleep to reduce power consumption. In some cases, it  
may be useful to reset the VCO control voltage by toggling CONFIG11 PLL_LPF_reset.  
External  
Loop  
Filter  
PLL Bypass  
Clock Multiplying PLL  
To internal  
DAC clock  
distribution  
CLKIN  
FREF/N  
FVCO/M  
N–Divider  
(1, 2, 4, 8)  
FVCO  
VCO  
FREF  
Charge  
Pump  
PFD  
CLKINC  
FPLL  
FVCO/2  
M-Divider  
( 1,2,4,8,16,32)  
÷2  
FVCO  
PLL Sleep  
PLL_sleep  
(CONFIG6)  
PLL_m(4:0)  
(CONFIG9)  
VCO_div2 PLL_bypass  
(CONFIG11) via CONFIG5  
PLL_gain(1:0),  
PLL_range(3:0)  
(CONFIG11)  
PLL_n(2:0)  
(CONFIG9)  
PLL_LPF_reset  
(CONFIG11)  
Figure 34. Functional Block Diagram for PLL  
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CLOCK INPUTS  
Figure 35 shows an equivalent circuit for the LVDS data input clock (DCLKP/N).  
27 kW  
DVDD  
DCLKP  
Note: Input and output common mode  
level self-biases to approximately DVDD/2,  
or 0.9 V normal.  
DVDD  
GND  
GND  
DCLKN  
27 kW  
Figure 35. DCLKP/N Equivalent Input Circuit  
Figure 36 shows an equivalent circuit for the DAC input clock (CLKIN/C).  
6 kW  
CLKVDD  
CLKIN  
Note: Input and output common mode  
level self-biases to approximately CLKVDD/2,  
or 0.9 V normal.  
CLKVDD  
GND  
GND  
CLKINC  
6 kW  
Figure 36. CLKIN/C Equivalent Input Circuit  
Figure 37 shows the preferred configuration for driving the CLKIN/CLKINC input clock with a differential  
ECL/PECL source.  
0.01 mF  
CLKIN  
+
Differential  
ECL  
or  
C
100 W  
AC  
(LV)PECL  
Source  
-
CLKINC  
82.5 W  
0.01 mF  
R
R
130 W  
T
T
130 W  
82.5 W  
V
TT  
Figure 37. Preferred Clock Input configuration With a Differential ECL/PECL Clock Source  
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LVDS DATA INTERFACING  
Interfacing very high-speed LVDS data and clocks presents a big challenge to system designers as they have  
unique constraints and are often implemented with specialized circuits to increase bandwidth. One such  
specialized LVDS circuit used in many FPGAs and ASICs is a SERializer-DESerializer (SERDES) block. For  
interfacing to the DAC5682Z, only the SERializer functionality of the SERDES block is required. SERDES drivers  
accept lower rate parallel input data and output a serial stream using a shift register at a frequency multiple of  
the data bit width. For example, a 4-bit SERDES block can accept parallel 4-bit input data at 250 MSPS and  
output serial data 1000 MSPS.  
External clock distribution for FPGA and ASIC SERDES drivers often have a chip-to-chip system constraint of a  
limited input clock frequency compared to the desired LVDS data rate. In this case, an internal clock multiplying  
PLL is often used in the FPGA or ASIC to drive the high-rate SERDES outputs. Due to this possible system  
clocking constraint, the DAC5682Z accommodates a scheme where a toggling LVDS SERDES data bit can  
provide a “data driven” half-rate clock (DCLK) from the data source. A DLL on-board the DAC is used to shift the  
DCLK edges relative to LVDS data to maintain internal setup and hold timing.  
To increase bandwidth of a single 16-bit input bus, the DAC5682Z assumes Double Data Rate (DDR) style  
interfacing of data relative to the half-rate DCLK. Refer to Figure 38 and Figure 39 providing an example  
implementation using FPGA-based LVDS data and clock interfaces to drive the DAC5682Z. In this example, an  
assumed system constraint is that the FPGA can only receive a 250 MHz maximum input clock while the desired  
DAC clock is 1000 MHz. A clock distribution chip such as the CDCM7005 is useful in this case to provide  
frequency and phase locked clocks at 250 MHz and 1000 MHz.  
FPGA / ASIC  
DAC5682Z DAC  
DAC  
TRF3703 AQM  
5V  
Term  
I-Signal  
LPF  
Antenna  
100  
SERDES  
D15  
1.0 GBPS  
(DDR)  
I
100  
100  
SERDES  
SERDES  
PA  
5V  
Term  
D0  
Q-Signal  
LPF  
Q
DAC  
SYNC  
To TX  
Feedback  
1.0 GHz  
DLL  
90  
100  
SERDES  
Control  
DCLK  
To RX  
Path  
opt.  
PLL  
0
500 MHz  
Toggling  
Data Bit  
4x Clock  
Multiplier  
Loop  
Filter  
~ 2.1 GHz  
TRF3761-X PLL/VCO  
DAC5682Z  
Control  
Div  
1/2/4  
Freq/Phase Locked  
250 MHz  
1.0 GHz  
VCO  
VCTRL_IN  
N-  
Divider  
10 MHz  
REF  
OSC  
100  
DLL  
Term  
÷1  
Loop  
Filter  
CDCM7005  
PFD  
Charge  
Pump  
REF_IN  
R-  
Div  
÷4  
CPOUT  
PLL  
Synth  
Loop  
Filter  
Clock Divider /  
Distribution  
Status & Control  
VCXO_STATUS  
REF_STATUS  
Status &  
Control  
VCXO  
CDCM7005  
Control  
PLL_LOCK  
1000 MHz  
TRF3761-X  
Control  
Figure 38. Example Direct Conversion System Diagram  
From the example provided by Figure 39, driving LVDS data into the DAC using SERDES blocks requires a  
parallel load of 4 consecutive data samples to shift registers. Color is used in the figure to indicate how data and  
clocks flow from the FPGA to the DAC5682Z. The figure also shows the use of the SYNCP/N input, which along  
with DCLK, requires 18 individual SERDES data blocks to drive the DAC’s input data FIFO that provides an  
elastic buffer to the DAC5682Z digital processing chain.  
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Using common “data driven”  
SERDES blocks, relative  
delays from CLK, SYNC and  
DATA are matched. (200pS)  
FPGA  
M
1000
250MHz  
÷1  
DCLK  
Lock Loop  
4
4
Ref CLK  
Gen &  
Sync  
CLKA  
(500MHz)  
CLKB  
(500MHz)  
System  
SYNC  
C  
250MHz  
(bit 15)  
4
4
D15N  
16  
To DAC  
1000MSPS DDR  
(2 bits/CLKIN cycle)  
16  
16  
16  
D0P  
4b SERDES  
(bit 0)  
LVDS  
D0N  
250 MHz (FPGA)  
DDR C
0
CLKA F  
CLKB F  
DLL Phase Offset control  
determines CLKA/B skew.  
SYNC input combines TXENABLE  
function (normally “1”) and SYNChronizer  
function (“0” to “1” transition)  
SYNC
1
SYNCP/N  
SERDES  
S3[15:0]  
S4[15:0]  
Sam
Sam
Sample “S3”  
Sample “S4”  
15] S1[15]  
Bit 0 Data Nibble  
S4[0] S3[0] S2[0] S1[0]  
D0P/N  
SERDES  
Figure 39. Example FPGA-Based LVDS Data Flow to DAC  
LVDS Inputs (D[15:0]P/N and SYNCP/N)  
To Adjacent  
LVDS Input  
D[15:0]P,  
SYNCP  
100 pF  
Total  
LVDS  
Receiver  
Ref Note (1)  
D[15:0]N,  
SYNCN  
Note (1):  
R
node common  
CENTER  
To Adjacent  
LVDS Input  
to all D[15:0]P/N and SYNCP/N  
receiver inputs  
Figure 40. D[15:0]P/N and SYNCP/N LVDS Input Configuration  
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Example  
V
1.40 V  
1.00 V  
A
DAC5682Z  
D[15:0]P,  
SYNCP  
V
B
LVDS  
V
V
A
400 mV  
0 V  
A,B  
Receiver  
V
A
V
=
COM1  
(V +V )/2  
D[15:0]N,  
SYNCN  
A
B
V
B
-400 mV  
V
B
GND  
1
0
Logical Bit  
Equivalent  
Figure 41. LVDS Data (DxP/N, SYNCP/N Pairs) Input Levels  
Example LVDS Data Input Levels  
APPLIED VOLTAGES  
RESULTING  
DEFERENTIAL  
VOLTAGE  
RESULTING  
COMMON-MODE  
VOLTAGE  
LOGICAL BIT BINARY  
EQUIVALENT  
VA  
VB  
VA,B  
VCOM1  
1.4 V  
1.0 V  
1.2 V  
0.8 V  
1.0 V  
1.4 V  
0.8 V  
1.2 V  
400 mV  
–400 mV  
400 mV  
–400 mV  
1.2 V  
1
0
1
0
1.0 V  
Note: AC Coupled  
DAC5682Z  
)
0.01 mF  
Self-bias (VBIAS  
DCLKP  
DCLKN  
VA,B  
DLL  
Circuit  
VA  
0.01 mF  
VB  
GND  
VCOM2 =~ DVDD/2  
Figure 42. LVDS Clock (DCLKP/N) Input Levels  
LVDS SYNCP/N Operation  
The SYNCP/N LVDS input control functions as a combination of Transmit Enable (TXENABLE) and  
Synchronization trigger. If SYNCP is low, the transmit chain is disabled so input data from the FIFO is ignored  
while zeros are inserted into the data path. If SYNCP is raised from low to high, a synchronization event occurs  
with behavior defined by individual control bits in registers CONFIG1, CONFIG5 and CONFIG6. The SYNCP/N  
control is sampled and input into the FIFO along with the other LVDS data to maintain timing alignment with the  
data bus. Refer to Figure 39.  
The software_sync_sel and software_sync controls in CONFIG3 provide a substitute for external SYNCP/N  
control; however, since the serial interface is used no timing control is provided with respect to the DAC clock.  
DLL OPERATION  
The DAC5682Z provides a digital Delay Lock Loop (DLL) to skew the LVDS data clock (DCLK) relative to the  
data bits, D[15:0] and SYNC, in order to maintain proper setup and hold timing. Since the DLL operates  
closed-loop, it requires a stable DCLK to maintain delay lock. Refer to the description of DLL_ifixed(2:0) and  
DLL_delay(3:0) control bits in the CONFIG10 register. Prior to initializing the DLL, the DLL_ifixed value should  
be programmed to match the expected DCLK frequency range. To initialize the DLL, refer to the DLL_Restart  
programming bit in the CONFIG8 register. After initialization, the status of the DLL can be verified by reading the  
DLL_Lock bit from STATUS0. See Startup Sequence below.  
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RECOMMENDED STARTUP SEQUENCE  
The following startup sequence is recommend to initialization the DAC5682Z:  
1. Supply all 1.8V (CLKVDD, DVDD, VFUSE) and 3.3V (AVDD and IOVDD) voltages.  
2. Provide stable CLKIN/C clock.  
3. Toggle RESETB pin for a minimum 25 nSec active low pulse width.  
4. Program all desired SIF registers. Set DLL_Restart bit during this write cycle. Ensure that DLL_ifixed and  
DLL_phase bits to correspond with the DCLKP/N frequency and delay.  
5. Provide stable DCLKP/N clock. (This can also be provided earlier in the sequence)  
6. Clear the DLL_Restart bit when the DCLKP/N clock is expected to be stable.  
7. Verify the status of DLL_Lock and repeat until set to ‘1’. DLL_Lock can be monitored by reading the  
STATUS0 register or by monitoring the SDO pin in 3-wire SIF mode. (See description for CONFIG14  
SDO_func_sel.)  
8. Enable transmit of data by asserting the LVDS SYNCP/N input or setting CONFIG3 SW_sync bit. (See  
description for CONFIG3 SW_sync and SW_sync_sel) The SYNC source must be held at a logic ‘1’ to  
enable data flow through the DAC.  
9. Provide data flow to LVDS D[15:0]P/N pins. If using the LVDS SYNCP/N input, data can be input  
simultaneous with the logic ‘1’ transition of SYNCP/N.  
CMOS DIGITAL INPUTS  
Figure 43 shows a schematic of the equivalent CMOS digital inputs of the DAC5682Z. SDIO and SCLK have  
pull-down resistors while RESETB and SDENB have pull-up resistors internal the DAC5682Z. See the  
specification table for logic thresholds. The pull-up and pull-down circuitry is approximately equivalent to 100k.  
IOVDD  
IOVDD  
internal  
digital in  
RESETB  
SDENB  
internal  
digital in  
SDIO  
SCLK  
IOGND  
IOGND  
Figure 43. CMOS/TTL Digital Equivalent Input  
DIGITAL SELF TEST MODE  
The DAC5682Z has a Digital Self Test (SLFTST) mode to designed to enable board level testing without  
requiring specific input data test patterns. The SLFTST mode is enabled via the CONFIG1 SLFTST_ena bit and  
results are only valid when CONFIG3 SLFTST_err_mask bit is cleared. An internal Linear Feedback Shift  
Register (LFSR) is used to generate the input test patterns for the full test cycle while a checksum result is  
computed on the digital signal chain outputs. The LVDS input data bus is ignored in SLFTST mode. After the test  
cycle completes, if the checksum result does not match a hardwired comparison value, the STATUS4  
SLFTST_err bit is set and will remain set until cleared by writing a ‘0’ to the SLFTST_err bit. A full self test cycle  
requires no more than 400,000 CLKIN/C clock cycles to complete and will automatically repeat until the  
SLFTEST_ena bit is cleared.  
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To initiate a the Digital Self Test:  
1. Provide a normal CLKIN/C input clock. (The PLL is not used in SLFTST mode)  
2. Provide a RESETB pulse to perform a hardware reset on device.  
3. Program the registers with the values shown in Table 9. These register values contain the settings to  
properly configure the SLFTST including SLFTST_ena and SLFTST_err_mask bits  
4. Provide a ‘1’ on the SYNCP/N input to initiate TXENABLE.  
5. Wait at a minimum of 400,000 CLKIN/C cycles for the SLFTST to complete. Example: If CLKIN = 1GHz, then  
the wait period is 400,000 × 1 / 1GHz = 400 µSec.  
6. Read STATUS4 SLFTST_err bit. If set, a self test error has occurred. The SLFTST_err status may  
optionally be programmed to output on the SDO pin if using the 3-bit SIF interface. See Table 9 Note (1).  
7. (Optional) The SLFTST function automatically repeats until SLFTST_ena bit is cleared. To the loop the test,  
write a ‘0’ to STATUS4 SLFTST_err to clear previous errors and continue at step 5 above.  
8. To continue normal operating mode, provide another RESETB pulse and reprogram registers to the desired  
normal settings.  
Table 9. Digital Self Test (SLFTST) Register Values  
REGISTER  
CONFIG1  
CONFIG2  
CONFIG3  
STATUS4  
CONFIG5  
CONFIG6  
CONFIG12  
CONFIG13  
CONFIG14(1)  
CONFIG15  
All others  
ADDRESS (hex)  
VALUE (Binary)  
00011000  
11101010  
10110000  
00000000  
00000110  
00001111  
00001010  
01010101  
00001010  
10101010  
Default  
VALUE (Hex)  
01  
02  
03  
04  
05  
06  
0C  
0D  
0E  
0F  
18  
EA  
B0  
00  
06  
0F  
0A  
55  
0A  
AA  
Default  
(1) If using a 3-bit SIF interface, the SDO pin can be programmed to report SLFTST_err status via the SDO_fun_sel(2:0) bits. In this case,  
set CONFIG14 = ‘10101010’ or AA hex.  
REFERENCE OPERATION  
The DAC5682Z uses a bandgap reference and control amplifier for biasing the full-scale output current. The  
full-scale output current is set by applying an external resistor RBIAS to pin BIASJ. The bias current IBIAS through  
resistor RBIAS is defined by the on-chip bandgap reference voltage and control amplifier. The default full-scale  
output current equals 16 times this bias current and can thus be expressed as:  
IOUTFS = 16 × IBIAS = 16 × VEXTIO / RBIAS  
Each DAC has a 4-bit independent coarse gain control via DACA_gain(3:0) and DACB_gain(3:0) in the  
CONFIG7 register. Using gain control, the IOUTFS can be expressed as:  
IOUTAFS = (DACA_gain + 1) × IBIAS = (DACA_gain + 1) × VEXTIO / RBIAS  
IOUTBFS = (DACB_gain + 1) × IBIAS = (DACB_gain + 1) × VEXTIO / RBIAS  
where VEXTIO is the voltage at terminal EXTIO. The bandgap reference voltage delivers an accurate voltage of  
1.2 V. This reference is active when terminal EXTLO is connected to AGND. An external decoupling capacitor  
CEXT of 0.1 µF should be connected externally to terminal EXTIO for compensation. The bandgap reference can  
additionally be used for external reference operation. In that case, an external buffer with high impedance input  
should be applied in order to limit the bandgap load current to a maximum of 100 nA. The internal reference can  
be disabled and overridden by an external reference by connecting EXTLO to AVDD. Capacitor CEXT may  
hence be omitted. Terminal EXTIO thus serves as either input or output node.  
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The full-scale output current can be adjusted from 20 mA down to 2 mA by varying resistor RBIAS or changing the  
externally applied reference voltage. The internal control amplifier has a wide input range, supporting the  
full-scale output current range of 20 dB.  
DAC TRANSFER FUNCTION  
The CMOS DAC’s consist of a segmented array of NMOS current sinks, capable of sinking a full-scale output  
current up to 20 mA. Differential current switches direct the current to either one of the complementary output  
nodes IOUT1 or IOUT2. (DACA = IOUTA1 or IOUTA2 and DACB = IOUTB1 or IOUTB2.) Complementary output  
currents enable differential operation, thus canceling out common mode noise sources (digital feed-through,  
on-chip and PCB noise), dc offsets, even order distortion components, and increasing signal output power by a  
factor of two.  
The full-scale output current is set using external resistor RBIAS in combination with an on-chip bandgap voltage  
reference source (+1.2 V) and control amplifier. Current IBIAS through resistor RBIAS is mirrored internally to  
provide a maximum full-scale output current equal to 16 times IBIAS  
.
The relation between IOUT1 and IOUT2 can be expressed as:  
IOUT1 = – IOUTFS – IOUT2  
We will denote current flowing into a node as – current and current flowing out of a node as + current. Since the  
output stage is a current sink the current can only flow from AVDD into the IOUT1 and IOUT2 pins. The output  
current flow in each pin driving a resistive load can be expressed as:  
IOUT1 = IOUTFS × (65536 – CODE) / 65536  
IOUT2 = IOUTFS × CODE / 65536  
where CODE is the decimal representation of the DAC data input word.  
For the case where IOUT1 and IOUT2 drive resistor loads RL directly, this translates into single ended voltages  
at IOUT1 and IOUT2:  
VOUT1 = AVDD – | IOUT1 | × RL  
VOUT2 = AVDD – | IOUT2 | × RL  
Assuming that the data is full scale (65536 in offset binary notation) and the RL is 25 , the differential voltage  
between pins IOUT1 and IOUT2 can be expressed as:  
VOUT1 = AVDD – | –0 mA | × 25 = 3.3 V  
VOUT2 = AVDD – | –20 mA | × 25 = 2.8 V  
VDIFF = VOUT1 – VOUT2 = 0.5 V  
Note that care should be taken not to exceed the compliance voltages at node IOUT1 and IOUT2, which would  
lead to increased signal distortion.  
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DAC OUTPUT SINC RESPONSE  
Due to sampled nature of a high-speed DAC’s, the well known sin(x)/x (or SINC) response can significantly  
attenuate higher frequency output signals. See the Figure 44 which shows the unitized SINC attenuation roll-off  
with respect to the final DAC sample rate in 4 Nyquist zones. For example, if the final DAC sample rate FS = 1.0  
GSPS, then a tone at 440MHz is attenuated by 3.0dB. Although the SINC response can create challenges in  
frequency planning, one side benefit is the natural attenuation of Nyquist images. The increased over-sampling  
ratio of the input data provided by the DAC5682Z’s 2x and 4x digital interpolation modes improve the SINC  
roll-off (droop) within the original signal’s band of interest  
Figure 44. Unitized DAC sin(x)/x (SINC) Response  
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ANALOG CURRENT OUTPUTS  
Figure 45 shows a simplified schematic of the current source array output with corresponding switches.  
Differential switches direct the current of each individual NMOS current source to either the positive output node  
IOUT1 or its complementary negative output node IOUT2. The output impedance is determined by the stack of  
the current sources and differential switches, and is typically >300 kin parallel with an output capacitance of 5  
pF.  
The external output resistors are referred to an external ground. The minimum output compliance at nodes  
IOUT1 and IOUT2 is limited to AVDD – 0.5 V, determined by the CMOS process. Beyond this value, transistor  
breakdown may occur resulting in reduced reliability of the DAC5682Z device. The maximum output compliance  
voltage at nodes IOUT1 and IOUT2 equals AVDD + 0.5 V. Exceeding the minimum output compliance voltage  
adversely affects distortion performance and integral non-linearity. The optimum distortion performance for a  
single-ended or differential output is achieved when the maximum full-scale signal at IOUT1 and IOUT2 does not  
exceed 0.5 V.  
AVDD  
R
R
LOAD  
LOAD  
IOUT1  
IOUT2  
S(1)  
S(N)  
S(2)  
S(2)C  
S(N)C  
S(1)C  
...  
Figure 45. Equivalent Analog Current Output  
The DAC5682Z can be easily configured to drive a doubly terminated 50cable using a properly selected RF  
transformer. Figure 46 and Figure 47 show the 50doubly terminated transformer configuration with 1:1 and 4:1  
impedance ratio, respectively. Note that the center tap of the primary input of the transformer has to be  
connected to AVDD to enable a dc current flow. Applying a 20 mA full-scale output current would lead to a 0.5  
VPP for a 1:1 transformer and a 1 VPP output for a 4:1 transformer. The low dc-impedance between IOUT1 or  
IOUT2 and the transformer center tap sets the center of the ac-signal at AVDD, so the 1 VPP output for the 4:1  
transformer results in an output between AVDD + 0.5 V and AVDD – 0.5 V.  
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AVDD  
(3.3 V)  
50 W  
1 : 1  
IOUT1  
IOUT2  
R
LOAD  
50 W  
100 W  
50 W  
AVDD (3.3 V)  
Figure 46. Driving a Doubly Terminated 50 Cable Using a 1:1 Impedance Ratio Transformer  
AVDD (3.3 V)  
100 W  
4 : 1  
IOUT1  
R
LOAD  
50 W  
IOUT2  
100 W  
AVDD (3.3 V)  
Figure 47. Driving a Doubly Terminated 50 Cable Using a 4:1 Impedance Ratio Transformer  
DESIGNING THE PLL LOOP FILTER  
To minimize phase noise given for a given fDAC and M/N, the values of PLL_gain and PLL_range are selected  
so that GVCO is minimized and within the MIN and MAX frequency for a given setting.  
The external loop filter components C1, C2, and R1 are set by the GVCO, M/N, the loop phase margin φd and the  
loop bandwidth ωd. Except for applications where abrupt clock frequency changes require a fast PLL lock time, it  
is suggested that φd be set to at least 80 degrees for stable locking and suppression of the phase noise side  
lobes. Phase margins of 60 degrees or less can be sensitive to board layout and decoupling details.  
See Figure 48, the recommend external loop filter topology. C1, C2, and R1 are calculated by the following  
equations:  
t2  
t3  
t1 - t2  
t3  
t32  
æ
ö
C1 = t1 1 -  
C2 =  
R1 =  
ç
÷
t1 t3 - t2  
(
)
è
ø
(1)  
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where,  
t1 =  
K K  
d
tan Φ + sec Φ  
d
1
VCO  
d
tan Φ + sec Φ  
(
d
t2 =  
t3 =  
)
d
2
w
tan Φ + sec Φ  
d
w
d
(
)
d
d
w
d
(2)  
charge pump current: iqp = 1 mA  
vco gain: KVCO = 2π × GVCO rad/V  
PFD Frequency: ωd 160 MHz  
phase detector gain: Kd = iqp ÷ (2 × π × M) A/rad  
An Excel spreadsheet is available from Texas Instruments for automatically calculating the values for C1, R1 and  
C2.  
DAC5682Z PLL  
LPF  
R1  
(Pin 64)  
PLL  
External  
Loop  
Filter  
C2  
C1  
Figure 48. Recommended External Loop Filter Topology  
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APPLICATIONS EXAMPLES  
DIGITAL INTERFACE AND CLOCKING CONSIDERATIONS FOR APPLICATION EXAMPLES  
The DAC5682Z’s LVDS digital input bus can be driven by an FPGA or digital ASIC. This input signal can be  
generated directly by the FPGA, or fed by a Texas Instruments Digital Up Converter (DUC) such as the GC5016  
or GC5316. Optionally, a GC1115 Crest Factor Reduction (CFR) or Digital Pre-Distortion (DPD) processor may  
be inserted in the digital signal chain for improving the efficiency of high-power RF amplifiers. For the details on  
the DAC’s high-rate digital interface, refer to the LVDS Data Interfacing section.  
A low phase noise clock for the DAC at the final sample rate can be generated by a VCXO and a Clock  
Synchronizer/PLL such as the Texas Instruments CDCM7005, which can also provide other system clocks at the  
VCXO frequency divided by /1, /2, /3, /4, /6, /8 or/16. An optional system clocking solution can use the DAC in  
clock multiplying PLL mode in order to avoid distributing a high-frequency clock at the DAC sample rate;  
however, the internal VCO phase noise of the DAC in PLL mode may degrade the quality of the DAC output  
signal.  
SINGLE COMPLEX INPUT, REAL IF OUTPUT RADIO  
Refer to Figure 49 for an example Single Complex Input, Real IF Output Radio. The DAC5682Z receives an  
interleaved complex I/Q baseband input data stream and increases the sample rate through interpolation by a  
factor of 2 or 4. By performing digital interpolation on the input data, undesired images of the original signal can  
be push out of the band of interest and more easily suppressed with analog filters. Complex mixing is available at  
each stage of interpolation using the CMIX0 and CMIX1 blocks to up-convert the signal to a frequency placement  
at a multiples ±Fdac/8 or ±Fdac/4. Only the real portion of the digital signal is converted by DAC-A while DAC-B  
can be programmed to sleep mode for reduced power consumption. The DAC output signal would typically be  
terminated with a transformer (see the Analog Current Output section). An IF filter, either LC or SAW, is used to  
suppress the DAC Nyquist zone images and other spurious signals before being mixed to RF with a mixer. The  
TRF3671 Frequency Synthesizer, with integrated VCO, may be used to drive the LO input of the mixer for  
frequencies between 375 and 2380 MHz.  
Interleaved  
I/Q Data  
3.3V  
FPGA  
DAC5682Z DAC  
3.3V  
100  
D15P/N  
D0P/N  
RF  
Processing  
DAC-A  
I
100  
100  
3.3V  
DAC-B  
Sleep  
Q
SYNCP/N  
DCLKP/N  
100  
DLL  
opt.  
PLL  
PLL/  
DLL  
375 MHz Min to 2380 MHz Max  
(Depends on divider and  
“dash #” of TRF3761)  
1000 MHz  
Loop  
Filter  
100  
250 MHz  
Div  
1/2/4  
VCXO  
÷4  
÷1  
VCO  
VCTRL_IN  
N-  
Divider  
Loop  
Filter  
Loop  
Filter  
Clock Divider /  
Distribution  
PLL  
PFD  
R-  
Div  
CDCM7005  
CPOUT  
10 MHz  
OSC  
TRF3761-X PLL/VCO  
Note: For clarity, only signal paths are shown.  
Figure 49. System Diagram of a Complex Input, Real IF Output Radio  
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APPLICATIONS EXAMPLES (continued)  
DUAL CHANNEL REAL IF OUTPUT RADIO  
Refer to Figure 50 for an example Dual Channel Real IF Output Radio. The DAC5682Z receives an interleaved  
A/B input data stream and increases the sample rate through interpolation by a factor of 2 or 4. By performing  
digital interpolation on the input data, undesired images of the original signal can be push out of the band of  
interest and more easily suppressed with analog filters. Real mixing is available at each stage of interpolation  
using the CMIX0 and CMIX1 blocks to up-convert the signal. (See Dual-Channel Real Upconversion section)  
Both DAC output signals would typically be terminated with a transformer (see the Analog Current Output  
section). An IF filter, either LC or SAW, is used to suppress the DAC Nyquist zone images and other spurious  
signals before being mixed to RF with a mixer. The TRF3671 Frequency Synthesizer, with integrated VCO, may  
be used to drive a common LO input of the mixers for frequencies between 375 and 2380 MHz. Alternatively, two  
separate TRF3761 synthesizers could be used for independent final RF frequency placement.  
Interleaved  
3.3V  
FPGA  
A/B Data  
DAC5682Z DAC  
3.3V  
100  
D15P/N  
D0P/N  
RF  
Processing  
DAC-A  
DAC-B  
I
3.3V  
100  
100  
3.3V  
3.3V  
RF  
Processing  
Q
SYNCP/N  
DCLKP/N  
3.3V  
100  
DLL  
opt.  
PLL  
PLL/  
DLL  
375 MHz Min to 2380 MHz Max  
(Depends on divider and  
“dash #” of TRF3761)  
1000 MHz  
Loop  
Filter  
100  
250 MHz  
Div  
1/2/4  
VCXO  
÷4  
÷1  
VCO  
VCTRL_IN  
N-  
Divider  
Loop  
Filter  
Loop  
Filter  
Clock Divider /  
Distribution  
PLL  
PFD  
R-  
Div  
CDCM7005  
CPOUT  
10 MHz  
OSC  
TRF3761-X PLL/VCO  
Note: For clarity,only signal paths are shown.  
Figure 50. System Diagram of a Dual Channel Real IF Output Radio  
DIRECT CONVERSION RADIO  
Refer to Figure 51 for an example Direct Conversion Radio. The DAC5682Z receives an interleaved complex I/Q  
baseband input data stream and increases the sample rate through interpolation by a factor of 2 or 4. By  
performing digital interpolation on the input data, undesired images of the original signal can be push out of the  
band of interest and more easily suppressed with analog filters.  
For a Zero IF (ZIF) frequency plan, complex mixing of the baseband signal is not required. Alternatively, for a  
Complex IF frequency plan the input data can be placed at an pre-placed at an IF within the bandwidth  
limitations of the interpolation filters. In addition, complex mixing is available at each stage of interpolation using  
the CMIX0 and CMIX1 blocks to up-convert the signal to a frequency placement at a multiples ±Fdac/8 or  
±Fdac/4. The output of both DAC channels is used to produce a Hilbert transform pair and can be expressed as:  
A(t) = I(t)cos(ωct) – Q(t)sin(ωct) m(t)  
A(t) = I(t)cos(ωct) – Q(t)sin(ωct) mh(t)  
(3)  
(4)  
where m(t) and mh(t) connote a Hilbert transform pair and ωc is the sum of the CMIX0 and CMIX1 frequencies.  
The complex output is input to an analog quadrature modulator (AQM) such as the Texas Instruments  
TRF3703-33 for a single side-band (SSB) up conversion to RF. A passive (resistor only) interface to the AQM is  
recommended, with an optional LC filter network. The TRF3671 Frequency Synthesizer with integrated VCO may  
be used to drive the LO input of the TRF3703-33 for frequencies between 375 and 2380 MHz. Upper  
single-sideband upconversion is achieved at the output of the analog quadrature modulator, whose output is  
expressed as:  
Copyright © 2007, Texas Instruments Incorporated  
Submit Documentation Feedback  
49  
Product Folder Link(s): DAC5682Z  
 
DAC5682Z  
www.ti.com  
SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
APPLICATIONS EXAMPLES (continued)  
RF(t) = I(t)cos(ωc + ωLO)t – Q(t)sin(ωc + ωLO)t  
(5)  
Flexibility is provided to the user by allowing for the selection of negative CMIX mixing sequences to produce a  
lower-sideband upconversion. Note that the process of complex mixing translates the signal frequency from 0 Hz  
means that the analog quadrature modulator IQ imbalance produces a sideband that falls outside the signal of  
interest. DC offset error in DAC and AQM signal path may produce LO feed-through at the RF output which may  
fall in the band of interest. To suppress the LO feed-through, the DAC5682Z provides a digital offset correction  
capability for both DAC-A and DAC-B paths. (See DAC_offset_ena bit in CONFIG3.)  
The complex IF architecture has several advantages over the real IF architecture:  
Uncalibrated side-band suppression ~ 35 dBc compared to 0 dBc for real IF architecture.  
Direct DAC to AQM interface – no amplifiers required  
Nonharmonic clock-related spurious signals fall out-of-band  
DAC 2nd Nyquist zone image is offset fDAC compared with fDAC– 2 × IF for a real IF architecture, reducing the  
need for filtering at the DAC output.  
Uncalibrated LO feed through for AQM is ~ 35 dBc and calibration can reduce or completely remove the LO  
feed through.  
5V  
Interleaved  
FPGA  
I/Q Data  
DAC5682Z DAC  
100  
D15P/N  
DAC-A  
I
D0P/N  
100  
RF OUT  
DAC-B  
100  
Q
SYNCP/N  
DCLKP/N  
90  
100  
DLL  
opt.  
PLL  
0
TRF3703-33 AQM  
PLL/  
DLL  
375 MHz Min to 2380 MHz Max  
(Depends on divider and  
“dash #” of TRF3761)  
1000 MHz  
Loop  
Filter  
100  
250 MHz  
Div  
1/2/4  
VCXO  
÷4  
÷1  
VCO  
VCTRL_IN  
N-  
Divider  
Loop  
Filter  
Loop  
Filter  
Clock Divider /  
Distribution  
PLL  
PFD  
R-  
Div  
CDCM7005  
CPOUT  
10 MHz  
OSC  
TRF3761-X PLL/VCO  
Note: For clarity,only signal paths are shown .  
Figure 51. System Diagram of Direct Conversion Radio  
CMTS/VOD TRANSMITTER  
The exceptional SNR of the DAC5682Z enables a dual-cable modem termination system (CMTS) or video on  
demand (VOD) QAM transmitter in excess of the stringent DOCSIS specification, with >74 dBc and 75 dBc in the  
adjacent and alternate channels.  
Refer to Figure 50 for an example Dual Channel Real IF Output Radio – this signal chain is nearly identical to a  
typical system using the DAC5682Z for a cost optimized dual channel two QAM transmitter. A GC5016 would  
take four separate symbol rate inputs and provide pulse shaping and interpolation to ~ 128 MSPS. The four QAM  
carriers would be combined into two groups of two QAM carriers with intermediate frequencies of approximately  
30 MHz to 40 MHz. The GC5016 would output two real data streams to one DAC5682Z through an FPGA for  
CMOS to LVDS translation. The DAC5682Z would function as a dual-channel device and provide 2x or 4x  
interpolation to increase the frequency of the 2nd Nyquist zone image. The two signals are then output through  
the two DAC outputs, through a transformer and to an RF upconverter.  
50  
Submit Documentation Feedback  
Copyright © 2007, Texas Instruments Incorporated  
Product Folder Link(s): DAC5682Z  
DAC5682Z  
www.ti.com  
SLLS853AAUGUST 2007REVISED NOVEMBER 2007  
APPLICATIONS EXAMPLES (continued)  
HIGH-SPEED ARBITRARY WAVEFORM GENERATOR  
The 1GSPS bandwidth input data bus combined with the 16-bit DAC resolution of the DAC5682Z allows  
wideband signal generation for test and measurement applications. In this case, interpolation is not desired by  
the FPGA-based waveform generator as it can make use of the full Nyquist bandwidth of up to 500MHz.  
FPGA  
DAC5682Z DAC  
100  
100  
D15P/N  
D0P/N  
DAC-A  
DAC-B  
Sleep  
100  
SYNCP/N  
DCLKP/N  
100  
DLL  
Figure 52. System Diagram of Arbitrary Waveform Generator  
Copyright © 2007, Texas Instruments Incorporated  
Submit Documentation Feedback  
51  
Product Folder Link(s): DAC5682Z  
PACKAGE OPTION ADDENDUM  
www.ti.com  
8-Nov-2007  
PACKAGING INFORMATION  
Orderable Device  
Status (1)  
Package Package  
Pins Package Eco Plan (2) Lead/Ball Finish MSL Peak Temp (3)  
Qty  
Type  
QFN  
QFN  
Drawing  
DAC5682ZIRGCR  
DAC5682ZIRGCT  
ACTIVE  
ACTIVE  
RGC  
64  
64  
2000  
250  
TBD  
TBD  
Call TI  
Call TI  
Call TI  
Call TI  
RGC  
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in  
a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2)  
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check  
http://www.ti.com/productcontent for the latest availability information and additional product content details.  
TBD: The Pb-Free/Green conversion plan has not been defined.  
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements  
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered  
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.  
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and  
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS  
compatible) as defined above.  
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame  
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)  
(3)  
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder  
temperature.  
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In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI  
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Addendum-Page 1  
IMPORTANT NOTICE  
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