DAC2904Y/2K [TI]

IC PARALLEL, WORD INPUT LOADING, 0.03 us SETTLING TIME, 14-BIT DAC, PQFP48, 7 X 7 MM, 1 MM HEIGHT, TQFP-48, Digital to Analog Converter;
DAC2904Y/2K
型号: DAC2904Y/2K
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

IC PARALLEL, WORD INPUT LOADING, 0.03 us SETTLING TIME, 14-BIT DAC, PQFP48, 7 X 7 MM, 1 MM HEIGHT, TQFP-48, Digital to Analog Converter

输入元件 转换器
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DAC2904  
www.ti.com.............................................................................................................................................. SBAS198C AUGUST 2001REVISED OCTOBER 2009  
Dual, 14-Bit, 125MSPS  
DIGITAL-TO-ANALOG CONVERTER  
Check for Samples: DAC2904  
1
FEATURES  
APPLICATIONS  
COMMUNICATIONS:  
2
125MSPS UPDATE RATE  
SINGLE SUPPLY: +3.3V or +5V  
HIGH SFDR: 78dB at fOUT = 10MHz  
LOW GLITCH: 2pV-s  
Base Stations, WLL, WLAN  
Baseband I/Q Modulation  
MEDICAL/TEST INSTRUMENTATION  
ARBITRARY WAVEFORM GENERATORS  
(ARB)  
DIRECT DIGITAL SYNTHESIS (DDS)  
space  
space  
LOW POWER: 310mW  
INTERNAL REFERENCE  
POWER-DOWN MODE: 23mW  
The DAC2904 combines high dynamic performance  
with a high update rate to create a cost-effective  
solution for a wide variety of waveform-synthesis  
applications:  
DESCRIPTION  
The DAC2904 is a monolithic, 14-bit, dual-channel,  
high-speed Digital-to-Analog Converter (DAC), and is  
optimized to provide high dynamic performance while  
dissipating only 310mW.  
Pin compatibility between family members  
provides 10-bit (DAC2900), 12-bit (DAC2902),  
and 14-bit (DAC2904) resolution.  
Operating with high update rates of up to 125MSPS,  
Pin compatible to the AD9767 dual DAC.  
Gain matching is typically 0.5% of full-scale, and  
offset matching is specified at 0.02% max.  
the  
DAC2904  
offers  
exceptional  
dynamic  
performance, and enables the generation of very-high  
output frequencies suitable for “Direct IF”  
applications. The DAC2904 has been optimized for  
communications applications in which separate I and  
Q data are processed while maintaining tight-gain  
and offset matching.  
The DAC2904 utilizes an advanced CMOS  
process; the segmented architecture minimizes  
output-glitch energy, and maximizes the dynamic  
performance.  
All digital inputs are +3.3V and +5V logic  
compatible. The DAC2904 has an internal  
reference circuit, and allows use in a multiplying  
configuration.  
Each DAC has a high-impedance differential-current  
output, suitable for single-ended or differential  
analog-output configurations.  
The DAC2904 is available in a TQFP-48 package,  
and is specified over the extended industrial  
temperature range of –40°C to +85°C.  
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.  
2
All trademarks are the property of their respective owners.  
PRODUCTION DATA information is current as of publication date.  
Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
Copyright © 2001–2009, Texas Instruments Incorporated  
 
DAC2904  
SBAS198C AUGUST 2001REVISED OCTOBER 2009.............................................................................................................................................. www.ti.com  
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with  
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.  
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more  
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.  
PACKAGE/ORDERING INFORMATION(1)  
SPECIFIED  
TEMPERATURE  
RANGE  
TRANSPORT  
MEDIA,  
QUANTITY  
PACKAGE-  
LEAD  
PACKAGE  
DESIGNATOR  
PACKAGE  
MARKING  
ORDERING  
NUMBER  
(2)  
PRODUCT  
DAC2904Y/250  
DAC2904Y/1K  
DAC2904IPFB  
Tape and Reel, 250  
Tape and Reel, 1k  
Tray, 250  
DAC2904Y  
TQFP-48  
PFB  
–40°C to +85°C  
DAC2904Y  
(1) 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.  
(2) Models with a slash (/) are available only in tape and reel media in the quantities indicated (for example, /1K indicates 1000 devices per  
reel). Ordering 1000 pieces of DAC2904Y/1K will get a single 1000-piece tape and reel.  
ABSOLUTE MAXIMUM RATINGS(1)  
DAC2904  
–0.3 to +6  
UNIT  
V
+VA to AGND  
+VD to DGND  
–0.3 to +6  
V
AGND to DGND  
+VA to +VD  
–0.3 to +0.3  
–6 to +6  
V
V
CLK, PD to DGND  
D0–D9 to DGND  
IOUT, I OUT to AGND  
BW, BYP to AGND  
REFIN, FSA to AGND  
INT/EXT to AGND  
Junction Temperature  
Case Temperature  
Storage Temperature  
–0.3 to VD +0.3  
–0.3 to VD +0.3  
–1 to VA + 0.3  
–0.3 to VA + 0.3  
–0.3 to VA + 0.3  
–0.3 to VA + 0.3  
+150  
V
V
V
V
V
V
°C  
°C  
°C  
+100  
+125  
(1) Stresses above those listed under absolute maximum ratings may cause permanent damage to the device. Exposure to absolute  
maximum conditions for extended periods may affect device reliability.  
2
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Copyright © 2001–2009, Texas Instruments Incorporated  
Product Folder Link(s): DAC2904  
 
DAC2904  
www.ti.com.............................................................................................................................................. SBAS198C AUGUST 2001REVISED OCTOBER 2009  
ELECTRICAL CHARACTERISTICS  
TMIN to TMAX, +VA = +5V, +VD = +3.3V, differential transformer coupled output, and 50Ω doubly-terminated, unless otherwise  
noted. Independent Gain Mode.  
DAC2904  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
RESOLUTION  
Resolution  
14  
Bits  
Output Update Rate (fCLOCK  
STATIC ACCURACY(1)  
)
125  
MSPS  
Differential Nonlinearity (DNL)  
Integral Nonlinearity (INL)  
TA = +25°C  
TA = +25°C  
±4.0  
±5.0  
LSB  
LSB  
DYNAMIC PERFORMANCE  
Spurious-Free Dynamic Range (SFDR)  
To Nyquist  
0dBFS Output  
–6dBFS Output  
–12dBFS Output  
71  
82  
77  
72  
82  
81  
81  
78  
72  
80  
69  
69  
64  
dBc  
dBc  
dBc  
dBc  
dBc  
dBc  
dBc  
dBc  
dBc  
dBc  
dBc  
dBc  
fOUT = 1MHz, fCLOCK = 50MSPS  
fOUT = 1MHz, fCLOCK = 26MSPS  
fOUT = 2.18MHz, fCLOCK = 52MSPS  
fOUT = 5.24MHz, fCLOCK = 52MSPS  
fOUT = 10.4MHz, fCLOCK = 78MSPS  
fOUT = 15.7MHz, fCLOCK = 78MSPS  
fOUT = 5.04MHz, fCLOCK = 100MSPS  
fOUT = 20.2MHz, fCLOCK = 100MSPS  
fOUT = 20.1MHz, fCLOCK = 125MSPS  
fOUT = 40.2MHz, fCLOCK = 125MSPS  
Spurious-Free Dynamic Range within a  
Window  
fOUT = 1MHz, fCLOCK = 50MSPS  
fOUT = 5.24MHz, fCLOCK = 52MSPS  
fOUT = 5.26MHz, fCLOCK = 78MSPS  
fOUT = 5.04MHz, fCLOCK = 125MSPS  
Total Harmonic Distortion (THD)  
fOUT = 1MHz, fCLOCK = 50MSPS  
fOUT = 5.24MHz, fCLOCK = 52MSPS  
fOUT = 5.26MHz, fCLOCK = 78MSPS  
fOUT = 5.04MHz, fCLOCK = 125MSPS  
Multitone Power Ratio  
2MHz span  
10MHz span  
10MHz span  
10MHz span  
80  
90  
88  
88  
88  
dBc  
dBc  
dBc  
dBc  
dBc  
dBc  
dBc  
dBc  
dBc  
–79  
–77  
–76  
–75  
–70  
Eight tone with 110kHz spacing  
0dBFS output  
fOUT = 2.0MHz to 2.99MHz, fCLOCK  
65MSPS  
=
80  
dBc  
Signal-to-Noise Ratio (SNR)  
fOUT = 5.02MHz, fCLOCK = 50MHz  
Signal-to-Noise and Distortion (SINAD)  
fOUT = 5.02MHz, fCLOCK = 50MHz  
Channel Isolation  
0dBFS output  
0dBFS output  
68  
67  
dBc  
dBc  
fOUT = 1MHz, fCLOCK = 52MSPS  
fOUT = 20MHz, fCLOCK = 125MSPS  
85  
77  
dBc  
dBc  
(1) At output lOUT, while driving a virtual ground.  
Copyright © 2001–2009, Texas Instruments Incorporated  
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DAC2904  
SBAS198C AUGUST 2001REVISED OCTOBER 2009.............................................................................................................................................. www.ti.com  
ELECTRICAL CHARACTERISTICS (continued)  
TMIN to TMAX, +VA = +5V, +VD = +3.3V, differential transformer coupled output, and 50Ω doubly-terminated, unless otherwise  
noted. Independent Gain Mode.  
DAC2904  
PARAMETER  
DYNAMIC PERFORMANCE, continued  
Output Settling Time(2)  
Output Rise Time(2)  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
To 0.1%  
30  
2
ns  
ns  
10% to 90%  
10% to 90%  
Output Fall Time(2)  
2
ns  
Glitch Impulse  
2
pV-s  
DC ACCURACY  
Full-Scale Output Range(3)(FSR)  
Output Compliance Range  
Gain Error—Full-Scale  
Gain Error  
All Bits HIGH, IOUT  
With internal reference  
With internal reference  
With internal reference  
With internal reference  
2
–1.0  
–5  
20  
+1.25  
+5  
mA  
V
±1  
±1  
%FSR  
%FSR  
%FSR  
–2.5  
–2.0  
+2.5  
+2.0  
Gain Matching  
0.5  
ppmFSR/°  
C
Gain Drift  
With internal reference  
With internal reference  
With internal reference  
±50  
Offset Error  
Offset Drift  
–0.02  
+0.02  
%FSR  
ppmFSR/°  
C
±0.2  
Power-Supply Rejection, +VA  
Power-Supply Rejection, +VD  
Output Noise  
+5V, ±10%  
+3.3V, ±10%  
–0.2  
+0.2 %FSR/V  
–0.025  
+0.025 %FSR/V  
IOUT = 20mA, RLOAD = 50Ω  
IOUT = 2mA  
50  
30  
pA/Hz  
pA/Hz  
kΩ  
Output Resistance  
200  
6
Output Capacitance  
IOUT, I OUT to ground  
pF  
REFERENCE/CONTROL AMP  
Reference Voltage  
+1.18  
+0.5  
+1.25  
±50  
+1.31  
+1.25  
V
ppmFSR/°  
C
Reference Voltage Drift  
Reference Output Current  
Reference Multiplying Bandwidth  
Input Compliance Range  
DIGITAL INPUTS  
100  
0.3  
nA  
MHz  
V
Logic Coding  
Straight Binary  
Logic High Voltage, VIH  
Logic Low Voltage, VIL  
Logic High Voltage, VIH  
Logic Low Voltage, VIL  
+VD = 5V  
+VD = 5V  
3.5  
5
0
V
V
1.2  
0.8  
+VD = 3.3V  
+VD = 3.3V  
+VD = 3.3V  
+VD = 3.3V  
2
3
V
0
V
(4)  
Logic High Current, IIH  
±10  
±10  
5
μA  
μA  
pF  
Logic Low Current  
Input Capacitance  
(2) Measured single-ended into 50Ω load.  
(3) Nominal full-scale output current is 32 ×IREF; see Applicationxx section for details.  
(4) Typically 45μA for the PD pin, which has an internal pull-down resistor.  
4
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Copyright © 2001–2009, Texas Instruments Incorporated  
Product Folder Link(s): DAC2904  
DAC2904  
www.ti.com.............................................................................................................................................. SBAS198C AUGUST 2001REVISED OCTOBER 2009  
ELECTRICAL CHARACTERISTICS (continued)  
TMIN to TMAX, +VA = +5V, +VD = +3.3V, differential transformer coupled output, and 50Ω doubly-terminated, unless otherwise  
noted. Independent Gain Mode.  
DAC2904  
PARAMETER  
POWER SUPPLY  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
Supply Voltages  
+VA  
+3.0  
+3.0  
+5  
+5.5  
+5.5  
V
V
+VD  
+3.3  
Supply Current  
(5)  
IVA  
+VA = +5V, lOUT = 20mA  
Power-Down mode  
58  
1.7  
4.2  
17  
65  
3
mA  
mA  
(5)  
IVA  
(5)  
IVD  
7
mA  
(6)  
IVD  
19.5  
350  
390  
mA  
Power Dissipation(5)  
Power Dissipation(6)  
Power Dissipation(5)  
Power Dissipation  
Thermal Resistance, TQFP-48  
θJA  
+VA = +5V, +VD = 3.3V, lOUT = 20mA  
+VA = +5V, +VD = 3.3V, lOUT = 20mA  
+VA = +5V, +VD = 3.3V, lOUT = 2mA  
Power-Down mode  
310  
348  
130  
23  
mW  
mW  
mW  
mW  
38  
60  
13  
°C/W  
°C/W  
θJC  
TEMPERATURE RANGE  
Specified  
Ambient  
Ambient  
–40  
–40  
+85  
+85  
°C  
°C  
Operating  
(5) Measured at fCLOCK = 25MSPS and fOUT = 1MHz.  
(6) Measured at fCLOCK = 100MSPS and fOUT = 40MHz.  
Copyright © 2001–2009, Texas Instruments Incorporated  
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DAC2904  
SBAS198C AUGUST 2001REVISED OCTOBER 2009.............................................................................................................................................. www.ti.com  
DEVICE INFORMATION  
PFB PACKAGE  
TQFP-48  
(TOP VIEW)  
48 47 46 45 44 43 42 41 40 39 38 37  
1
2
3
4
5
6
7
8
9
36 D0-2  
35 D1-2  
34 D2_2  
33 D3_2  
D13_1 (MSB)  
D12_1  
D11_1  
D10_1  
D9_1  
32  
D4_2  
D8_1  
31 D5_2  
30 D6_2  
29 D7_2  
28 D8_2  
DAC2904  
D7_1  
D6_1  
D5_1  
D4_1 10  
D3_1 11  
D2_1 12  
27  
D9_2  
26 D10_2  
25 D11_2  
13 14 15 16 17 18 19 20 21 22 23 24  
TERMINAL FUNCTIONS  
TERMINAL  
NAME  
D[13:0]_1  
DGND  
+VD  
NO.  
1–14  
15, 21  
16, 22  
17  
DESCRIPTION  
Data port DAC1, data bit 13 (MSB) to bit 0 (LSB)  
Digital ground  
Digital supply, +3.0V to +5.5V  
DAC1 input latches write signal  
Clock input DAC1  
WRT1  
CLK1  
18  
CLK2  
19  
Clock input DAC2  
WRT2  
D[13:0]_2  
PD  
20  
DAC2 input latches write signal  
Data port DAC2, data bit 13 (MSB) to bit 0 (LSB).  
23–36  
37  
Power-down function control input. H = DAC in power-down mode; L = DAC in normal operation (internal pull-down for default L).  
Analog ground  
AGND  
38  
IOUT  
2
39  
Current output DAC2. Full-scale with all bits of data port 2 high.  
Complementary current output DAC2. Full-scale with all bits of data port 2 low.  
Full-scale adjust, DAC2. Connect external RSET resistor.  
I OUT  
2
40  
FSA2  
GSET  
REFIN  
FSA1  
41  
42  
Gain-setting mode (H = one resistor, L = two resistors)  
43  
Internal reference voltage output; external reference voltage input. Bypass with 0.1μF capacitor to AGND for internal reference operation.  
Full-scale adjust, DAC1. Connect external RSET resistor.  
44  
I OUT  
IOUT  
1
45  
Complementary current output DAC1. Full-scale with all bits of data port 1 low.  
Current output DAC1. Full-scale with all bits of data port 1 high.  
Analog supply, +3.0V to +5.5V  
1
46  
+VA  
NC  
47  
48  
No connection  
6
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DAC2904  
www.ti.com.............................................................................................................................................. SBAS198C AUGUST 2001REVISED OCTOBER 2009  
tS  
tH  
DATA IN  
D[13:0](n)  
D[13:0](n + 1)  
tLPW  
WRT1  
WRT2  
tCPW  
CLK1  
CLK2  
tSET  
IOUT1  
IOUT  
IOUT  
50%  
(n)  
(n + 1)  
IOUT2  
tPD  
TIMING REQUIREMENTS  
PARAMETER  
MIN  
TYP  
MAX  
UNIT  
ns  
tS  
Input setup time  
Input hold time  
2
1.5  
3.5  
0
tH  
ns  
tLPW, tCPW  
tCW  
Latch/Clock pulse width  
4
ns  
Delay rising CLK edge to rising WRT edge  
Propagation delay  
tPW – 2  
ns  
tPD  
1
ns  
tSET  
Settling time (0.1%)  
30  
ns  
DIGITAL INPUTS AND TIMING  
The data input ports of the DAC2904 accept a standard positive coding with data bit D13 being the most  
significant bit (MSB). The converter outputs support a clock rate of up to 125MSPS. The best performance will  
typically be achieved with a symmetric duty cycle for write and clock; however, the duty cycle may vary as long  
as the timing specifications are met. Also, the set-up and hold times may be chosen within their specified limits.  
All digital inputs of the DAC2904 are CMOS compatible. The logic thresholds depend on the applied digital  
supply voltages, such that they are set to approximately half the supply voltage; Vth = +VD/2 (±20% tolerance).  
The DAC2904 is designed to operate with a digital supply (+VD) of +3.0V to +5.5V.  
The two converter channels within the DAC2904 consist of two independent, 14-bit, parallel data ports. Each  
DAC channel is controlled by its own set of write (WRT1, WRT2) and clock (CLK1, CLK2) inputs. Here, the WRT  
lines control the channel input latches and the CLK lines control the DAC latches. The data is first loaded into the  
input latch by a rising edge of the WRT line. This data is presented to the DAC latch on the following falling edge  
of the WRT signal. On the next rising edge of the CLK line, the DAC is updated with the new data and the analog  
output signal will change accordingly. The double latch architecture of the DAC2904 results in a defined  
sequence for the WRT and CLK signals, expressed by parameter tCW . A correct timing is observed when the  
rising edge of CLK occurs at the same time, or before, the rising edge of the WRT signal. This condition can  
simply be met by connecting the WRT and CLK lines together. Note that all specifications were measured with  
the WRT and CLK lines connected together.  
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DAC2904  
SBAS198C AUGUST 2001REVISED OCTOBER 2009.............................................................................................................................................. www.ti.com  
TYPICAL CHARACTERISTICS  
At TA = +25°C, +VD = +3.3V, +VA = +5V, differential transformer coupled, IOUT = 20mA, 50Ω double terminated load, and  
SFDR up to Nyquist, unless otherwise noted.  
TYPICAL DNL  
TYPICAL INL  
4
3
6
5
4
2
3
1
2
0
1
0
-1  
-2  
-3  
-4  
-1  
-2  
-3  
-4  
0
2k  
4k  
6k  
8k  
10k  
12k  
14k  
16k  
0
2k  
4k  
6k  
8k  
10k  
12k  
14k  
16k  
Code  
Code  
Figure 1.  
Figure 2.  
SFDR vs fOUT AT 26MSPS  
SFDR vs fOUT AT 52MSPS  
90  
85  
80  
75  
70  
65  
60  
90  
85  
80  
75  
70  
65  
60  
-6dBFS  
0dBFS  
0dBFS  
-6dBFS  
-12dBFS  
-12dBFS  
0
2
4
6
8
10  
12  
0
5
10  
15  
20  
25  
fOUT (MHz)  
fOUT (MHz)  
Figure 3.  
Figure 4.  
SFDR vs fOUT AT 100MSPS  
SFDR vs fOUT AT 78MSPS  
85  
80  
75  
70  
65  
60  
55  
85  
80  
75  
70  
65  
60  
55  
50  
0dBFS  
-6dBFS  
-6dBFS  
-12dBFS  
-12dBFS  
0dBFS  
0
5
10  
15  
20  
25  
30  
35  
0
5
10  
15  
20  
25  
30  
35  
40  
45  
fOUT (MHz)  
fOUT (MHz)  
Figure 5.  
Figure 6.  
8
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Product Folder Link(s): DAC2904  
DAC2904  
www.ti.com.............................................................................................................................................. SBAS198C AUGUST 2001REVISED OCTOBER 2009  
TYPICAL CHARACTERISTICS (continued)  
At TA = +25°C, +VD = +3.3V, +VA = +5V, differential transformer coupled, IOUT = 20mA, 50Ω double terminated load, and  
SFDR up to Nyquist, unless otherwise noted.  
SFDR vs fOUT AT 125MHz  
SFDR vs IOUTFS AND fOUT AT 78MSPS  
85  
80  
75  
70  
65  
60  
55  
50  
82  
80  
78  
76  
74  
72  
70  
68  
66  
64  
62  
20mA  
10mA  
-6dBFS  
-12dBFS  
5mA  
0dBFS  
0dBFs  
0
10  
20  
30  
fOUT (MHz)  
40  
50  
60  
0
5
10  
15  
20  
25  
fOUT (MHz)  
Figure 7.  
Figure 8.  
SFDR AT 125MSPS vs TEMPERATURE  
GAIN AND OFFSET DRIFT  
0.8  
0.6  
0.004  
0.003  
0.002  
0.001  
0
90  
85  
80  
75  
70  
65  
60  
55  
50  
2MHz  
Offset Error  
0.4  
10MHz  
0.2  
20MHz  
40MHz  
0
-0.2  
-0.4  
-0.6  
-0.8  
-0.001  
-0.002  
-0.003  
-0.004  
Gain Error  
-40  
-20  
0
20  
40  
60  
80 85  
-40  
-20  
0
20  
40  
60  
80  
100  
Temperature (°C)  
Temperature (°C)  
Figure 9.  
Figure 10.  
IVD vs RATIO AT +VD = +3.3V  
IVA vs IOUTFS  
60  
55  
50  
45  
40  
35  
30  
25  
20  
15  
10  
25  
20  
15  
10  
5
125MSPS  
100MSPS  
78MSPS  
52MSPS  
26MSPS  
0
0
5
10  
15  
20  
25  
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45  
Ratio (fOUT/fCLK  
)
IOUTFS (mA)  
Figure 11.  
Figure 12.  
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TYPICAL CHARACTERISTICS (continued)  
At TA = +25°C, +VD = +3.3V, +VA = +5V, differential transformer coupled, IOUT = 20mA, 50Ω double terminated load, and  
SFDR up to Nyquist, unless otherwise noted.  
SINGLE-TONE SFDR  
SINGLE-TONE SFDR  
10  
0
10  
0
fCLOCK = 100MSPS  
fOUT = 20.2MHz  
fCLOCK = 52MSPS  
fOUT = 5.23MHz  
-10  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
-90  
-10  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
-90  
Amplitude = 0dBFS  
Amplitude = 0dBFS  
0
5.2  
10.4  
15.6  
20.8  
26  
0
10  
20  
30  
40  
50  
Frequency (MHz)  
Frequency (MHz)  
Figure 13.  
Figure 14.  
DUAL-TONE SFDR  
FOUR-TONE SFDR  
10  
0
10  
0
fCLOCK = 78MSPS  
fOUT1 = 9.44MHz  
fOUT2 = 10.44MHz  
Amplitude = 0dBFS  
fCLOCK = 50MSPS  
fOUT1 = 6.25MHz  
fOUT2 = 6.75MHz  
fOUT3 = 7.25MHz  
fOUT4 = 7.75MHz  
Amplitude = 0dBFS  
-10  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
-90  
-10  
-20  
-30  
-40  
-50  
-60  
-70  
-80  
-90  
0
7.8  
15.6  
23.4  
31.2  
39  
0
5
10  
15  
20  
25  
Frequency (MHz)  
Frequency (MHz)  
Figure 15.  
Figure 16.  
WCDMA—ACPR  
-30  
-40  
fCLOCK = 61.44MSPS  
PCHANNEL = -13dBm  
ACPR = -69.2dB  
-50  
-60  
-70  
-80  
-90  
-100  
-110  
-120  
-130  
Center: 15.36MHz; Span: 14MHz  
Figure 17.  
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APPLICATION INFORMATION  
THEORY OF OPERATION  
DAC TRANSFER FUNCTION  
The architecture of the DAC2904 uses the current  
steering technique to enable fast switching and a high  
update rate. The core element within the monolithic  
DAC is an array of segmented current sources that  
are designed to deliver a full-scale output current of  
up to 20mA, as shown in Figure 18. An internal  
decoder addresses the differential current switches  
each time the DAC is updated and a corresponding  
output current is formed by steering all currents to  
Each of the DACs in the DAC2904 has a set of  
complementary current output, IOUT and I  
. The  
OUT  
full-scale output current, IOUTFS, is the summation of  
the two complementary output currents:  
IOUTFS = IOUT + IOUT  
(1)  
The individual output currents depend on the DAC  
code and can be expressed as:  
Code  
´
16,384  
IOUT = IOUTFS  
either output summing node, IOUT or I  
. The  
OUT  
(2)  
complementary outputs deliver a differential output  
signal, which improves the dynamic performance  
through reduction of even-order harmonics,  
common-mode signals (noise), and double the  
peak-to-peak output signal swing by a factor of two,  
compared to single-ended operation.  
Code  
16,384  
I
OUT = IOUTFS ´ (16,383 -  
)
(3)  
where Code is the decimal representation of the DAC  
data input word. Additionally, IOUTFS is a function of  
the reference current IREF, which is determined by the  
reference voltage and the external setting resistor,  
The segmented architecture results in a significant  
reduction of the glitch energy, improves the dynamic  
performance (SFDR), and DNL. The current outputs  
maintain a very high output impedance of greater  
than 200kΩ.  
RSET  
.
VREF  
RSET  
IOUTFS = 32 ´ IREF = 32 ´  
(4)  
The full-scale output current is determined by the  
ratio of the internal reference voltage (1.25V) and an  
external resistor, RSET. The resulting IREF is internally  
multiplied by a factor of 32 to produce an effective  
DAC output current that can range from 2mA to  
In most cases the complementary outputs will drive  
resistive loads or a terminated transformer. A signal  
voltage will develop at each output according to:  
VOUT = IOUT ´ RLOAD  
(5)  
VOUT = IOUT ´ RLOAD  
(6)  
20mA, depending on the value of RSET  
.
The value of the load resistance is limited by the  
output compliance specification of the DAC2904. To  
maintain specified linearity performance, the voltage  
The DAC2904 is split into a digital and an analog  
portion, each of which is powered through its own  
supply pin. The digital section includes edge-triggered  
input latches and the decoder logic, while the analog  
section comprises the current source array with its  
associated switches, and the reference circuitry.  
for IOUT and I  
should not exceed the maximum  
OUT  
allowable compliance range.  
The two single-ended output voltages can be  
combined to find the total differential output swing:  
(2 ´ Code - 16,383)  
VOUTDIFF = VOUT - VOUT  
=
´ IOUTFS ´ RLOAD  
16,384  
(7)  
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+VD  
+VD  
+VA  
lOUT  
1
Data Input  
Port 1  
DAC1  
Segmented Switches  
Current Sources  
Input  
Latch 1  
DAC  
Latch 1  
D[13:0]_1  
IOUT  
1
REFIN  
WRT1  
CLK1  
CLK2  
WRT2  
FSA1  
FSA2  
GSET  
PD  
Reference  
Control Amplifier  
DAC2904  
lOUT  
2
Data Input  
Port 2  
DAC2  
Segmented Switches  
Current Sources  
Input  
Latch 2  
DAC  
Latch 2  
D[13:0]_2  
IOUT  
2
DGND  
DGND  
AGND  
Figure 18. Block Diagram of the DAC2904  
given by the breakdown voltage of the CMOS  
process, and exceeding it will compromise the  
reliability of the DAC2904, or even cause permanent  
damage. With the full-scale output set to 20mA, the  
positive compliance equals 1.25V, operating with an  
analog supply of +VA = 5V. Note that the compliance  
range decreases to about 1V for a selected output  
current of IOUTFS = 2mA. Care should be taken that  
the configuration of DAC2904 does not exceed the  
compliance range to avoid degradation of the  
distortion performance and integral linearity.  
ANALOG OUTPUTS  
The DAC2904 provides two complementary current  
outputs, IOUT and I . The simplified circuit of the  
OUT  
analog output stage representing the differential  
topology is shown in Figure 19. The output  
impedance of IOUT and I  
combination of the differential switches, along with  
the current sources and associated parasitic  
capacitances.  
results from the parallel  
OUT  
Best distortion performance is typically achieved with  
the maximum full-scale output signal limited to  
approximately 0.5VPP. This is the case for a 50Ω  
doubly terminated load and a 20mA full-scale output  
current. A variety of loads can be adapted to the  
output of the DAC2904 by selecting a suitable  
transformer while maintaining optimum voltage levels  
+VA  
DAC2904  
at IOUT and I  
. Furthermore, using the differential  
OUT  
output configuration in combination with a transformer  
will be instrumental for achieving excellent distortion  
performance. Common-mode errors, such as  
even-order harmonics or noise, can be substantially  
reduced. This is particularly the case with high output  
frequencies.  
IOUT  
RL  
IOUT  
RL  
For those applications requiring the optimum  
distortion and noise performance, it is recommended  
to select a full-scale output of 20mA. A lower  
full-scale range down to 2mA may be considered for  
applications that require a low power consumption,  
but can tolerate a slightly reduced performance level.  
Figure 19. Equivalent Analog Output  
The signal voltage swing that may develop at the two  
outputs, IOUT and I  
, is limited by a negative and  
OUT  
positive compliance. The negative limit of –1V is  
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OUTPUT CONFIGURATIONS  
DIFFERENTIAL WITH TRANSFORMER  
The current outputs of the DAC2904 allow for a  
variety of configurations, some of which are illustrated  
in Table 1. As mentioned previously, utilizing the  
converter differential outputs will yield the best  
dynamic performance. Such a differential output  
circuit may consist of an RF transformer or a  
differential amplifier configuration. The transformer  
configuration is ideal for most applications with ac  
coupling, while op amps will be suitable for a  
dc-coupled configuration.  
Using an RF transformer provides a convenient way  
of converting the differential output signal into a  
single-ended signal while achieving excellent  
dynamic performance (see Figure 20). The  
appropriate transformer should be carefully selected  
based on the output frequency spectrum and  
impedance requirements. The differential transformer  
configuration has the benefit of significantly reducing  
common-mode signals, thus improving the dynamic  
performance over a wide range of frequencies.  
Furthermore, by selecting a suitable impedance ratio  
(winding ratio), the transformer can be used to  
provide optimum impedance matching while  
controlling the compliance voltage for the converter  
outputs. The model shown, ADTT1-1 (by  
Mini-Circuits), has a 1:1 ratio and may be used to  
interface the DAC2904 to a 50Ω load. This results in  
Table 1. Input Coding vs Analog Output Current  
INPUT CODE (D13 - D0)  
11 1111 1111 1111  
10 0000 0000 0000  
00 0000 0000 0000  
IOUT  
20mA  
10mA  
0mA  
I OUT  
0mA  
10mA  
20mA  
a 25Ω load for each of the outputs, IOUT and I  
The output signals are ac-coupled and inherently  
isolated because of its magnetic coupling.  
.
OUT  
The single-ended configuration may be considered  
for applications requiring a unipolar output voltage.  
Connecting a resistor from either one of the outputs  
to ground will convert the output current into a  
ground-referenced voltage signal. To improve on the  
dc linearity by maintaining a virtual ground, an I-to-V  
or op amp configuration may be considered.  
As shown in Figure 20, the transformer center tap is  
connected to ground. This forces the voltage swing  
on IOUT and I  
to be centered at 0V. In this case  
OUT  
the two resistors, RL, may be replaced with one,  
RDIFF, or omitted altogether. This approach should  
only be used if all components are close to each  
other, and if the VSWR is not important. A complete  
power transfer from the DAC output to the load can  
be realized, but the output compliance range should  
be observed. Alternatively, if the center tap is not  
connected, the signal swing will be centered at (RL ×  
IOUTFS/2). However, in this case, the two load  
resistors, RL, must be used to enable the necessary  
dc-current flow for both outputs.  
space  
space  
space  
space  
space  
ADTT1-1  
(Mini-Circuits)  
1:1  
IOUT  
RL  
RS  
RDIFF  
50W  
DAC2904  
50W  
100W  
IOUT  
RL  
50W  
Figure 20. Differential Output Configuration Using an RF Transformer  
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DIFFERENTIAL CONFIGURATION USING AN  
OP AMP  
slew-limitations or into an overload condition; both  
would cause excessive distortion. The difference  
amplifier can easily be modified to add a level shift for  
applications requiring the single-ended output voltage  
to be unipolar; that is, swing between 0V and +2V.  
If the application requires a dc-coupled output, a  
difference amplifier may be considered, as shown in  
Figure 21. Four external resistors are needed to  
configure the voltage-feedback op amp OPA690 as a  
difference amplifier performing the differential to  
single-ended conversion. Under the configuration  
shown, the DAC2904 generates a differential output  
signal of 0.5VPP at the load resistors, RL. The resistor  
values shown were selected to result in a symmetric  
25Ω loading for each of the current outputs since the  
input impedance of the difference amplifier is in  
parallel to resistors RL, and should be considered.  
DUAL TRANSIMPEDANCE OUTPUT  
CONFIGURATION  
The circuit example of Figure 22 shows the signal  
output currents connected into the summing junctions  
of the dual voltage-feedback op amp OPA2690 that is  
set up as a transimpedance stage, or -to-V converter.  
With this circuit, the DAC output will be kept at a  
virtual ground, minimizing the effects of output  
impedance variations, which results in the best dc  
linearity (INL). As mentioned previously, care should  
be taken not to drive the amplifier into slew-rate  
limitations, and produce unwanted distortion.  
R2  
402W  
R1  
200W  
IOUT  
+5V  
VOUT  
DAC2904  
IOUT  
OPA690  
50W  
1/2  
R3  
COPT  
-VOUT = IOUT · RF1  
OPA2690  
200W  
-5V +5V  
RL  
28.7W  
R4  
402W  
RL  
26.1W  
RF1  
DAC2904  
CF1  
IOUT  
CD1  
Figure 21. Difference Amplifier Provides  
Differential to Single-Ended Conversion and  
DC-Coupling  
RF2  
CF2  
IOUT  
CD2  
The OPA690 is configured for a gain of two.  
Therefore, operating the DAC2904 with a 20mA  
full-scale output will produce a voltage output of ±1V.  
This requires the amplifier to operate off of a dual  
power supply (±5V). The tolerance of the resistors  
typically sets the limit for the achievable  
common-mode rejection. An improvement can be  
obtained by fine-tuning resistor R4.  
1/2  
· RF2  
-VOUT = IOUT  
OPA2690  
50W  
-5V  
This configuration typically delivers a lower level of ac  
Figure 22. Dual, Voltage-Feedback Amplifier  
OPA2690 Forms Differential Transimpedance  
Amplifier  
performance  
than  
the  
previously  
discussed  
transformer solution because the amplifier introduces  
another source of distortion. Suitable amplifiers  
should be selected based on the slew rate, harmonic  
distortion, and output swing capabilities. High-speed  
amplifiers like the OPA690 or OPA687 may be  
considered. The ac performance of this circuit may be  
improved by adding a small capacitor, CDIFF, between  
The dc gain for this circuit is equal to feedback  
resistor RF. At high frequencies, the DAC output  
impedance (CD1, CD2) will produce a zero in the noise  
gain for the OPA2690 that may cause peaking in the  
closed-loop frequency response.  
the outputs IOUT and I  
(see Figure 21). This will  
OUT  
introduce a real pole to create a low-pass filter in  
order to slew-limit the DAC fast output signal steps,  
which otherwise could drive the amplifier into  
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CF is added across RF to compensate for this noise  
gain peaking. To achieve a flat transimpedance  
frequency response, the pole in each feedback  
network should be set to:  
INTERFACING ANALOG QUADRATURE  
MODULATORS  
One of the main applications for the dual-channel  
DAC is baseband I- and Q-channel transmission for  
digital communications. In this application, the DAC is  
followed by an analog quadrature modulator,  
modulating an IF carrier with the baseband data, as  
shown in Figure 25. Often, the input stages of these  
quadrate modulators consist of npn-type transistors  
that require a dc bias (base) voltage greater than  
0.8V. The wide output compliance range (–10V to  
+1.25V) allows for a direct dc-coupling between the  
DAC2904 and the quadrature modulator.  
1
GBP  
=
2pRFCF 4pRFCD  
(8)  
with GBP = Gain Bandwidth Product of the OPA  
which will give  
approximately:  
a
corner frequency f–3dB of  
GBP  
f
=
-3dB  
2pRFCD  
(9)  
Figure 24 shows an example of a dc-coupled  
interface with dc level-shifting, using a precision  
resistor network. An ac-coupled interface (see  
Figure 26) has the advantage that the common-mode  
levels at the input of the modulator can be set  
independently of those at the output of the DAC.  
Furthermore, no voltage loss is obtained in this setup.  
The full-scale output voltage is simply defined by the  
product of IOUTFS × RF, and has a negative unipolar  
excursion. To improve on the ac performance of this  
circuit, adjustment of RF and/or IOUTFS should be  
considered. Further extensions of this application  
example may include adding a differential filter at the  
OPA2690 output followed by a transformer, in order  
to convert to a single-ended signal.  
VDC  
SINGLE-ENDED CONFIGURATION  
R3  
Using a single load resistor connected to one of the  
DAC outputs, a simple current-to-voltage conversion  
can be accomplished. The circuit in Figure 23 shows  
a 50Ω resistor connected to IOUT, providing the  
termination of the further connected 50Ω cable.  
Therefore, with a nominal output current of 20mA, the  
DAC produces a total signal swing of 0V to 0.5V into  
the 25Ω load.  
VOUT1  
VOUT  
1
R4  
IOUT1  
DAC2904  
IOUT1  
IOUT  
1
IOUTFS = 20mA  
IOUT  
1
VOUT = 0V to +0.5V  
IOUT  
R5  
DAC2904  
IOUT  
50W  
50W  
25W  
Figure 24. DC-Coupled Interface to Quadrature  
Modulator Applying Level Shifting  
Figure 23. Driving a Doubly-Terminated 50Ω  
Cable Directly  
Different load resistor values may be selected as long  
as the output compliance range is not exceeded.  
Additionally, the output current, IOUTFS, and the load  
resistor may be mutually adjusted to provide the  
desired output signal swing and performance.  
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VOUT ~ 0VP to 1.20VP  
VIN ~ 0.6VP to 1.8VP  
IIN  
IREF  
IIN  
DAC2904  
IOUT1  
IREF  
IOUT  
1
Signal  
Conditioning  
RF  
S
QIN  
IOUT2  
QREF  
IOUT  
2
Quadrature Modulator  
Signal conditioning (level-shifting) may be required to ensure correct dc common-mode levels at the input of the quadrature modulator.  
Figure 25. Generic Interface to a Quadrature Modulator  
VDC  
INTERNAL REFERENCE OPERATION  
The DAC2904 has an on-chip reference circuit which  
R1  
IOUT  
1
DAC2904  
consists of a 1.25V bandgap reference and two  
control amplifiers, one for each DAC. The full-scale  
output current, IOUTFS, of the DAC2904 is determined  
by the reference voltage, VREF, and the value of  
resistor RSET. IOUTFS can be calculated by:  
0.01mF  
0.01mF  
IOUT  
1
VOUT1  
VOUT  
1
IOUT  
1
IOUT  
1
50W  
50W  
RLOAD  
R2  
VREF  
IOUTFS = 32 ´ IREF = 32 ´  
RSET  
(10)  
Figure 26. AC-Coupled Interface to Quadrature  
Modulator Applying Level Shifting  
As shown in Figure 27, the external resistor RSET  
connects to the FSA pin (Full-Scale Adjust). The  
reference control amplifier operates as a V-to-I  
converter producing a reference current, IREF, which  
is determined by the ratio of VREF and RSET (see  
+5V  
Equation 10). The full-scale output current, IOUTFS  
,
results from multiplying IREF by a fixed factor of 32.  
+VA  
DAC2904  
Using the internal reference, a 2kΩ resistor value  
results in a full-scale output of approximately 20mA.  
Resistors with a tolerance of 1% or better should be  
considered. Selecting higher values, the output  
current can be adjusted from 20mA down to 2mA.  
Operating the DAC2904 at lower than 20mA output  
currents may be desirable for reasons of reducing the  
total power consumption, improving the distortion  
performance, or observing the output compliance  
voltage limitations for a given load condition.  
VREF  
IREF  
=
RSET  
FSA  
Ref  
Control  
Amp  
Current  
Sources  
REFIN  
RSET  
2kW  
0.1mF  
+1.25V Ref.  
It is recommended to bypass the REFIN pin with a  
ceramic chip capacitor of 0.1μF or more. The control  
amplifier is internally compensated, and its  
small-signal bandwidth is approximately 0.3MHz.  
Figure 27. Internal Reference Configuration  
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GAIN SETTING OPTIONS  
+5V  
The full-scale output current on the DAC2904 can be  
set two ways: either for each of the two DAC  
+VA  
DAC2904  
channels independently or for both channels  
VREF  
IREF  
=
RSET  
simultaneously. For the independent gain set mode,  
the GSET pin (pin 42) must be low (that is, connected  
to AGND). In this mode, two external resistors are  
required—one RSET connected to the FSA1 pin (pin  
44) and the other to the FSA2 pin (pin 41). In this  
configuration, the user has the flexibility to set and  
adjust the full-scale output current for each DAC  
independently, allowing for the compensation of  
possible gain mismatches elsewhere within the  
transmit signal path.  
FSA  
Ref  
Control  
Amp  
Current  
Sources  
REFIN  
External  
Reference  
RSET  
+1.25V Ref.  
Figure 28. External Reference Configuration  
Alternatively, bringing the GSET pin high (that is,  
connected to +VA), the DAC2904 will switch into the  
simultaneous gain set mode. Now the full-scale  
output current of both DAC channels is determined by  
only one external RSET resistor connected to the  
FSA1 pin. The resistor at the FSA2 pin may be  
removed; however, this is not required because this  
pin is not functional in this mode and the resistor has  
no effect on the gain equation. The formula for  
deriving the correct RSET remains unchanged; for  
example, RSET = 2kΩ will result in a 20mA output for  
both DACs.  
GROUNDING, DECOUPLING AND LAYOUT  
INFORMATION  
Proper grounding and bypassing, short lead lengths,  
and the use of ground planes are particularly  
important for high-frequency designs. Multilayer  
printed circuit boards (PCBs) are recommended for  
best performance because they offer distinct  
advantages such as minimization of ground  
impedance, separation of signal layers by ground  
layers, etc.  
The DAC2904 uses separate pins for its analog and  
digital supply and ground connections. The  
placement of the decoupling capacitor should be such  
that the analog supply (+VA) is bypassed to the  
analog ground (AGND), and the digital supply  
bypassed to the digital ground (DGND). In most  
cases 0.1μF ceramic chip capacitors at each supply  
pin are adequate to provide a low impedance  
decoupling path. Keep in mind that the effectiveness  
of these capacitors largely depends on the proximity  
to the individual supply and ground pins. Therefore,  
they should be located as close as physically  
possible to those device leads. Whenever possible,  
the capacitors should be located immediately under  
each pair of supply/ground pins on the reverse side of  
the PCB. This layout approach will minimize the  
parasitic inductance of component leads and PCB  
runs.  
EXTERNAL REFERENCE OPERATION  
The internal reference can be disabled by simply  
applying an external reference voltage into the REFIN  
pin, which in this case functions as an input, as  
shown in Figure 28. The use of an external reference  
may be considered for applications that require higher  
accuracy and drift performance, or to add the ability  
of dynamic gain control.  
While a 0.1μF capacitor is recommended to be used  
with the internal reference, it is optional for the  
external reference operation. The reference input,  
REFIN, has a high input impedance (1MΩ) and can  
easily be driven by various sources. Note that the  
voltage range of the external reference should stay  
within the compliance range of the reference input.  
POWER-DOWN MODE  
Further supply decoupling with surface-mount  
tantalum capacitors (1μF to 4.7μF) may be added as  
needed in proximity of the converter.  
The DAC2904 features a power-down function which  
can be used to reduce the total supply current to less  
than 6mA over the specified supply range of 3.0V to  
5.5V. Applying a logic high to the PD pin will initiate  
the power-down mode, while a logic low enables  
normal operation. When left unconnected, an internal  
active pulldown circuit will enable the normal  
operation of the converter.  
Low noise is required for all supply and ground  
connections to the DAC2904. It is recommended to  
use a multilayer PCB utilizing separate power and  
ground planes. Mixed signal designs require  
particular attention to the routing of the different  
supply currents and signal traces. Generally, analog  
supply and ground planes should only extend into  
analog signal areas, such as the DAC output signal  
and the reference signal. Digital supply and ground  
Copyright © 2001–2009, Texas Instruments Incorporated  
Submit Documentation Feedback  
17  
Product Folder Link(s): DAC2904  
 
DAC2904  
SBAS198C AUGUST 2001REVISED OCTOBER 2009.............................................................................................................................................. www.ti.com  
planes must be confined to areas covering digital  
circuitry, including the digital input lines connecting to  
the converter, as well as the clock signal. The analog  
and digital ground planes should be joined together at  
one point underneath the DAC. This can be realized  
with a short track of approximately 1/8 inch (3,0 mm).  
connected together at the supply connector of the  
PCB. In the case of only one supply voltage being  
available to power the DAC, ferrite beads along with  
bypass capacitors may be used to create an LC filter.  
This will generate a low-noise analog supply voltage,  
which can then be connected to the +VA supply pin of  
the DAC2904.  
The power to the DAC2904 should be provided  
through the use of wide PCB runs or planes. Wide  
runs will present a lower trace impedance, further  
optimizing the supply decoupling. The analog and  
digital supplies for the converter should only be  
While designing the layout, it is important to keep the  
analog signal traces separated from any digital line,  
in order to prevent noise coupling onto the analog  
signal path.  
18  
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Copyright © 2001–2009, Texas Instruments Incorporated  
Product Folder Link(s): DAC2904  
DAC2904  
www.ti.com.............................................................................................................................................. SBAS198C AUGUST 2001REVISED OCTOBER 2009  
REVISION HISTORY  
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.  
Changes from Revision B (November, 2003) to Revision C .......................................................................................... Page  
Updated document format to current standards ................................................................................................................... 1  
Added DAC2904IPFB orderable to Package/Ordering Information table ............................................................................. 2  
Copyright © 2001–2009, Texas Instruments Incorporated  
Submit Documentation Feedback  
19  
Product Folder Link(s): DAC2904  
PACKAGE OPTION ADDENDUM  
www.ti.com  
21-May-2010  
PACKAGING INFORMATION  
Status (1)  
Eco Plan (2)  
MSL Peak Temp (3)  
Samples  
Orderable Device  
Package Type Package  
Drawing  
Pins  
Package Qty  
Lead/  
Ball Finish  
(Requires Login)  
DAC2904IPFB  
DAC2904Y/1K  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
TQFP  
TQFP  
TQFP  
TQFP  
TQFP  
PFB  
PFB  
PFB  
PFB  
PFB  
48  
48  
48  
48  
48  
250  
1000  
1000  
250  
Green (RoHS  
& no Sb/Br)  
CU NIPDAU Level-2-260C-1 YEAR  
Green (RoHS  
& no Sb/Br)  
CU NIPDAU Level-2-260C-1 YEAR  
CU NIPDAU Level-2-260C-1 YEAR  
CU NIPDAU Level-2-260C-1 YEAR  
CU NIPDAU Level-2-260C-1 YEAR  
DAC2904Y/1KG4  
DAC2904Y/250  
DAC2904Y/250G4  
Green (RoHS  
& no Sb/Br)  
Green (RoHS  
& no Sb/Br)  
250  
Green (RoHS  
& no Sb/Br)  
(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.  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
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 to Customer on an annual basis.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
21-May-2010  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
16-Jul-2012  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
DAC2904Y/1K  
DAC2904Y/250  
TQFP  
TQFP  
PFB  
PFB  
48  
48  
1000  
250  
330.0  
330.0  
16.4  
16.4  
9.6  
9.6  
9.6  
9.6  
1.5  
1.5  
12.0  
12.0  
16.0  
16.0  
Q2  
Q2  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
16-Jul-2012  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
DAC2904Y/1K  
DAC2904Y/250  
TQFP  
TQFP  
PFB  
PFB  
48  
48  
1000  
250  
367.0  
367.0  
367.0  
367.0  
38.0  
38.0  
Pack Materials-Page 2  
MECHANICAL DATA  
MTQF019A – JANUARY 1995 – REVISED JANUARY 1998  
PFB (S-PQFP-G48)  
PLASTIC QUAD FLATPACK  
0,27  
0,17  
0,50  
M
0,08  
36  
25  
37  
24  
48  
13  
0,13 NOM  
1
12  
5,50 TYP  
7,20  
SQ  
Gage Plane  
6,80  
9,20  
SQ  
8,80  
0,25  
0,05 MIN  
0°7°  
1,05  
0,95  
0,75  
0,45  
Seating Plane  
0,08  
1,20 MAX  
4073176/B 10/96  
NOTES: A. All linear dimensions are in millimeters.  
B. This drawing is subject to change without notice.  
C. Falls within JEDEC MS-026  
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