THS1031IPWLE [TI]

10-CH 10-BIT PROPRIETARY METHOD ADC, PARALLEL ACCESS, PDSO28, PLASTIC, TSSOP-28;
THS1031IPWLE
型号: THS1031IPWLE
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

10-CH 10-BIT PROPRIETARY METHOD ADC, PARALLEL ACCESS, PDSO28, PLASTIC, TSSOP-28

光电二极管 转换器
文件: 总41页 (文件大小:719K)
中文:  中文翻译
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THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E – NOVEMBER 1999 – REVISED MARCH 2002  
28-PIN TSSOP/SOIC PACKAGE  
(TOP VIEW)  
10-Bit Resolution, 30 MSPS  
Analog-to-Digital Converter  
Configurable Input Functions:  
– Single-Ended  
– Single-Ended With Analog Clamp  
– Single-Ended With Programmable Digital  
Clamp  
AGND  
AV  
DD  
AIN  
1
28  
27  
26  
25  
24  
23  
22  
21  
20  
19  
18  
DV  
2
DD  
I/O0  
I/O1  
I/O2  
I/O3  
I/O4  
I/O5  
I/O6  
I/O7  
I/O8  
VREF  
3
REFBS  
REFBF  
MODE  
4
5
– Differential  
6
Built-In Programmable Gain Amplifier  
(PGA)  
REFTF  
REFTS  
CLAMPIN  
CLAMP  
REFSENSE  
7
8
Differential Nonlinearity: ±0.3 LSB  
Signal-to-Noise: 56 dB  
9
10  
11  
Spurious Free Dynamic Range: 60 dB  
Adjustable Internal Voltage Reference  
Straight Binary/2s Complement Output  
Out-of-Range Indicator  
I/O9 12  
OVR 13  
17 WR  
16 OE  
15 CLK  
DGND 14  
Power-Down Mode  
description  
The THS1031 is a CMOS, low-power, 10-bit, 30 MSPS analog-to-digital converter (ADC) that can operate with  
a supply range from 3 V to 5.5 V. The THS1031 has been designed to give circuit developers flexibility. The  
analog input to the THS1031 can be either single-ended or differential. This device has a built-in clamp amplifier  
whose clamp input level can be driven from an external dc source or from an internal high-precision 10-bit digital  
clamp level programmable via an internal CLAMP register. A 3-bit PGA is included to maintain SNR for small  
signals. The THS1031 provides a wide selection of voltage references to match the user’s design requirements.  
For more design flexibility, the internal reference can be bypassed to use an external reference to suit the dc  
accuracy and temperature drift requirements of the application. The out-of-range output indicates any  
out-of-range condition in THS1031’s input signal. The format of digital output can be coded in either unsigned  
binary or 2s complement.  
The speed, resolution, and single-supply operation of the THS1031 are suited to applications in set-top-box  
(STB), video, multimedia, imaging, high-speed acquisition, and communications. The built-in clamp function  
allows dc restoration of video signal and is suitable for video applications. The speed and resolution ideally suit  
charge-couple device (CCD) input systems such as color scanners, digital copiers, digital cameras, and  
camcorders. A wide input voltage range between REFBS and REFTS allows the THS1031 to be applied in both  
imaging and communications systems.  
The THS1031C is characterized for operation from 0°C to 70°C, while the THS1031I is characterized for  
operation from –40°C to 85°C.  
AVAILABLE OPTIONS  
PACKAGED DEVICES  
T
A
28-TSSOP (PW)  
THS1031CPW  
THS1031IPW  
28-SOIC (DW)  
THS1031CDW  
THS1031IDW  
0°C to 70°C  
40°C to 85°C  
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.  
Copyright 2002, Texas Instruments Incorporated  
PRODUCTION DATA information is current as of publication date.  
Products conform to specifications per the terms of Texas Instruments  
standard warranty. Production processing does not necessarily include  
testing of all parameters.  
1
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
functional block diagram  
Power Down  
10-Bit  
Clamp  
10  
DAC  
Control  
WR  
CLAMPIN  
Register  
CLAMP  
Clamp  
Amplifier  
3
10  
Core  
ADC  
AIN  
Sample  
and  
Hold  
Output  
Buffer  
I/O(09)  
PGA  
REFTS  
REFBS  
DAC  
OVR  
OE  
Internal  
Reference  
Buffer  
A
B
MODE  
REFTF  
REFBF  
Timing  
Circuit  
VBG  
ORG  
GND  
REFSENSE  
VREF  
CLK  
2
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
Terminal Functions  
TERMINAL  
NAME  
AGND  
AIN  
AV  
I/O  
DESCRIPTION  
NO.  
1
I
I
I
I
I
I
I
I
Analog ground  
Analog input  
27  
28  
19  
20  
15  
14  
2
Analog supply  
DD  
CLAMP  
CLAMPIN  
CLK  
High to enable clamp mode, low to disable clamp mode  
Connect to an external analog clamp reference input.  
Clock input  
DGND  
Digital ground  
DV  
Digital driver supply  
DD  
I/O0  
I/O1  
I/O2  
I/O3  
I/O4  
I/O5  
I/O6  
I/O7  
I/O8  
I/O9  
3
4
5
6
7
8
9
10  
11  
12  
Digital I/O bit 0 (LSB)  
Digital I/O bit 1  
Digital I/O bit 2  
Digital I/O bit 3  
Digital I/O bit 4  
Digital I/O bit 5  
Digital I/O bit 6  
Digital I/O bit 7  
Digital I/O bit 8  
Digital I/O bit 9 (MSB)  
I/O  
MODE  
OE  
23  
16  
13  
25  
24  
18  
22  
21  
26  
17  
I
I
Mode input  
High to 3-state the data bus, low to enable the data bus  
Out-of-range indicator  
OVR  
O
I
REFBS  
REFBF  
REFSENSE  
REFTF  
REFTS  
VREF  
Reference bottom sense  
Reference bottom decoupling  
Reference sense  
I
I
I
Reference top decoupling  
Reference top sense  
I
I/O Internal and external reference  
Write strobe  
WR  
I
3
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
absolute maximum ratings over operating free-air temperature (unless otherwise noted)  
Supply voltage range: AV  
to AGND, DV  
to DGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to 6.5 V  
DD  
DD  
AGND to DGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to 0.3 V  
AV to DV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5 V to 6.5 V  
DD  
DD  
Mode input voltage range, MODE to AGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to AV  
Reference voltage input range, REFTF, REFTB, REFTS, REFBS to AGND . . . . . . . 0.3 V to AV  
Analog input voltage range, AIN to AGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to AV  
Reference input voltage range, VREF to AGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to AV  
Reference output voltage range, VREF to AGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to AV  
Clock input voltage range, CLK to AGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to AV  
Digital input voltage range, digital input to DGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to DV  
Digital output voltage range, digital output to DGND . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to DV  
+ 0.3 V  
+ 0.3 V  
+ 0.3 V  
+ 0.3 V  
+ 0.3 V  
+ 0.3 V  
+ 0.3 V  
+ 0.3 V  
DD  
DD  
DD  
DD  
DD  
DD  
DD  
DD  
Operating junction temperature range, T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 150°C  
Storage temperature range, T  
Lead temperature 1,6 mm (1/16 in) from case for 10 seconds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300°C  
J
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65°C to 150°C  
stg  
Stresses beyond those listed under absolute maximum ratingsmay cause permanent damage to the device. These are stress ratings only, and  
functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditionsis not  
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.  
recommended operating conditions  
digital inputs  
MIN NOM  
MAX  
UNIT  
Clock input  
0.8 × AV  
DD  
High-level input voltage, V  
IH  
V
All other inputs  
Clock input  
0.8 × DV  
DD  
0.2 × AV  
0.2 × DV  
DD  
Low-level input voltage, V  
V
IL  
All other inputs  
DD  
analog inputs  
MIN  
REFBS  
1
NOM  
MAX  
REFTS  
2
UNIT  
Analog input voltage, V  
I(AIN)  
(PGA = 1x, top, bottom, or external reference mode)  
V
V
V
Reference input voltage, V  
I(VREF)  
Clamp input voltage, V  
0.1  
AV 0.1  
DD  
I(CLAMPIN)  
power supply  
MIN NOM  
MAX  
5.5  
UNIT  
AV  
DD  
3
3
3.3  
3.3  
Supply voltage  
Maximum sampling rate = 30 MSPS  
V
DV  
5.5  
DD  
REFTS, REFBS reference voltages (MODE = AV  
)
DD  
PARAMETER  
MIN NOM  
MAX  
AV  
UNIT  
V
REFTS  
REFBS  
Reference input voltage (top)  
1
DD  
Reference input voltage (bottom)  
0
AV 1  
V
DD  
Differential input voltage (REFTS REFBS)  
Switched input capacitance on REFTS or REFBS  
1
2
V
0.6  
pF  
sampling rate and resolution  
PARAMETER  
MIN NOM  
MAX  
UNIT  
MHz  
Bits  
f
s
Sample frequency  
Resolution  
5
30  
10  
4
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
electrical characteristics over recommended operating conditions, AV  
= 3 V, DV  
= 3 V,  
DD  
DD  
f = 30 MSPS/50% duty cycle, MODE = AV , 2-V input span from 0.5 V to 2.5 V, external reference,  
s
DD  
PGA = 1X, T = T  
to T  
(unless otherwise noted)  
A
min  
max  
analog inputs  
PARAMETER  
MIN  
TYP  
MAX  
UNIT  
V
V
I(AIN)  
Analog input voltage  
REFBS  
REFTS  
C
Switched sampling input capacitance  
Full power bandwidth (3 dB)  
1.2  
150  
100  
pF  
I
BW  
MHz  
µA  
I
DC leakage current (input = ± FS)  
lkg  
VREF reference voltages  
PARAMETER  
Internal 1-V reference voltage (REFSENSE = VREF)  
MIN  
TYP  
MAX  
1.05  
2.10  
2
UNIT  
V
0.95  
1.90  
1
1
2
Internal 2-V reference voltage (REFSENSE = AV  
)
V
SS  
)
External reference voltage (REFSENSE = AV  
DD  
V
Reference input resistance (REFSENSE = AV , MODE = AV /2)  
DD DD  
18  
kΩ  
REFTF, REFBF reference voltages  
PARAMETER  
TEST CONDITIONS  
MIN  
1
TYP  
MAX  
2
UNIT  
Differential input voltage (REFTF REFBF)  
V
AV  
AV  
AV  
AV  
AV  
AV  
AV  
AV  
AV  
AV  
= 3 V  
= 5 V  
= 3 V  
= 5 V  
= 3 V  
= 5 V  
= 3 V  
= 5 V  
= 3 V  
= 5 V  
1.3  
2
1.5  
2.5  
2
1.7  
3
DD  
DD  
DD  
DD  
DD  
DD  
DD  
DD  
DD  
DD  
Input common mode voltage (REFTF + REFBF)/2  
V
V
V
V
VREF = 1 V  
3
REFTF voltage (MODE = AV  
REFBF voltage (MODE = AV  
)
DD  
2.5  
3.5  
1
VREF = 2 V  
VREF = 1 V  
VREF = 2 V  
2
)
DD  
0.5  
1.5  
680  
V
Input resistance between REFTF and REFBF  
5
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
electrical characteristics over recommended operating conditions, AV  
= 3 V, DV  
= 3 V,  
DD  
DD  
f = 30 MSPS/50% duty cycle, MODE = AV , 2-V input span from 0.5 V to 2.5 V, external reference,  
s
DD  
PGA = 1X, T = T  
to T  
(unless otherwise noted) (continued)  
A
min  
max  
dc accuracy  
PARAMETER  
MIN  
TYP  
±1  
MAX  
±2  
±1  
2
UNIT  
LSB  
INL  
Integral nonlinearity (see Note 1)  
DNL  
Differential nonlinearity (see Note 2)  
Offset error (see Note 3)  
Gain error (see Note 4)  
Missing code  
±0.3  
0.4  
LSB  
%FSR  
1.4  
3.5 %FSR  
No missing code assured  
NOTES: 1. Integral nonlinearity refers to the deviation of each individual code from a line drawn from zero to full scale. The point used as zero  
occurs 1/2 LSB before the first code transition. The full-scale point is defined as a level 1/2 LSB beyond the last code transition. The  
deviation is measured from the center of each particular code to the true straight line between these two endpoints.  
2. AnidealADCexhibitscodetransitionsthatareexactly1LSBapart. DNListhedeviationfromthisidealvalue.Thereforethismeasure  
indicates how uniform the transfer function step sizes are. The ideal step size is defined here as the step size for the device under  
n
test (i.e., (last transition level first transition level) ÷ (2 2)). Using this definition for DNL separates the effects of gain and offset  
error. A minimum DNL better than 1 LSB ensures no missing codes.  
3. Offset error is defined as the difference in analog input voltage between the ideal voltage and the actual voltage that will switch  
the ADC output from code 0 to code 1. The ideal voltage level is determined by adding the voltage corresponding to 1/2 LSB to the  
bottom reference level. The voltage corresponding to 1 LSB is found from the difference of top and bottom references divided by  
the number of ADC output levels (1024).  
4. Gain error is defined as the difference in analog input voltage between the ideal voltage and the actual voltage that will switch  
the ADC output from code 1022 to code 1023. The ideal voltage level is determined by subtracting the voltage corresponding to 1.5  
LSB from the top reference level. The voltage corresponding to 1 LSB is found from the difference of top and bottom references  
divided by the number of ADC output levels (1024).  
dynamic performance (ADC and PGA)  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
9
MAX  
UNIT  
f = 3.5 MHz  
8.2  
f = 3.5 MHz, AV  
f = 15 MHz  
= 5 V  
= 5 V  
= 5 V  
= 5 V  
= 5 V  
= 5 V  
= 5 V  
= 5 V  
= 5 V  
= 5 V  
8.8  
7.7  
7.64  
60  
DD  
ENOB  
SFDR  
THD  
Effective number of bits  
Bits  
f = 15 MHz, AV  
f = 3.5 MHz  
DD  
55  
f = 3.5 MHz, AV  
f = 15 MHz  
63  
DD  
Spurious free dynamic range  
Total harmonic distortion  
Signal-to-noise ratio  
dB  
dB  
dB  
dB  
48  
f = 15 MHz, AV  
f = 3.5 MHz  
52.4  
DD  
58.2 54.7  
f = 3.5 MHz, AV  
f = 15 MHz  
68.7  
47  
51.9  
56  
DD  
f = 15 MHz, AV  
f = 3.5 MHz  
DD  
51.2  
51.1  
f = 3.5 MHz, AV  
f = 15 MHz  
55  
DD  
SNR  
53  
f = 15 MHz, AV  
f = 3.5 MHz  
49.3  
56  
DD  
f = 3.5 MHz, AV  
55  
DD  
SINAD Signal-to-noise and distortion  
f = 15 MHz  
48.1  
47.7  
f = 15 MHz, AV  
DD  
6
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
electrical characteristics over recommended operating conditions, AV  
= 3 V, DV  
= 3 V,  
DD  
DD  
f = 30 MSPS/50% duty cycle, MODE = AV , 2-V input span from 0.5 V to 2.5 V, external reference,  
s
DD  
PGA = 1X, T = T  
to T  
(unless otherwise noted) (continued)  
A
min  
max  
PGA  
PARAMETER  
MIN  
TYP  
0.5  
3
MAX  
UNIT  
V/V  
Gain range (linear scale)  
Gain step size (linear scale)  
Gain error from nominal  
Number of control bits  
0.5  
4
V/V  
3%  
Bits  
clamp amplifier and clamp DAC  
PARAMETER  
MIN  
TYP  
MAX  
UNIT  
Bits  
V
Resolution  
10  
DAC output range  
REFBF  
REFTF  
1
DAC differential nonlinearity  
DAC integral nonlinearity  
Clamping analog output voltage range  
Clamping analog output voltage error  
1  
LSB  
LSB  
V
±1  
0.1  
AV 0.1  
DD  
40  
40  
mV  
clock  
PARAMETER  
MIN  
33  
TYP  
MAX  
UNIT  
ns  
t
t
t
t
Clock cycle  
c
Pulse duration, clock high  
Pulse duration, clock high  
15  
16.5  
16.5  
ns  
w(CKH)  
w(CKL)  
d(o)  
15  
ns  
Clock to data valid, delay time  
Pipeline latency  
25  
ns  
3
4
Cycles  
ns  
t
Aperture delay time  
d(AP)  
Aperture uncertainty (jitter)  
2
ps  
timing  
PARAMETER  
MIN  
0
TYP  
MAX  
20  
UNIT  
ns  
t
t
t
t
t
t
t
Output disable to Hi-Z output, delay time  
Output enable to output valid, delay time  
Output disable to write enable, delay time  
Write disable to output enable, delay time  
Write pulse duration  
d(DZ)  
d(DEN)  
d(OEW)  
d(WOE)  
w(WP)  
su  
0
20  
ns  
12  
12  
15  
5
ns  
ns  
ns  
Input data setup time  
ns  
Input data hold time  
5
ns  
h
power supply  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
30.6  
94  
MAX  
45  
UNIT  
I
Operating supply current  
Power dissipation  
Standby power  
AV  
AV  
AV  
AV  
= 3 V, MODE = AGND  
mA  
CC  
DD  
DD  
DD  
DD  
= DV  
= DV  
= DV  
= 3 V  
135  
DD  
DD  
DD  
P
D
mW  
mW  
= 5 V  
160  
3
P
= 3 V, MODE = AGND  
5
D(STBY)  
7
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
PARAMETER MEASUREMENT INFORMATION  
OE  
See Note A  
t
w(WP)  
t
t
d(WOE)  
d(OEW)  
WE  
t
t
h
d(DZ)  
t
t
d(DEN)  
su  
Hi-Z  
Hi-Z  
Output  
Input  
Output  
I/O  
NOTE A: All timing measurements are based on 50% of edge transition.  
Figure 1. Write Timing Diagram  
Sample 2  
Sample 3  
Sample 1  
Sample 5  
Sample 4  
Analog Input  
t
c
t
w(CKL)  
t
(CKH)  
Input Clock  
See  
Note A  
t
d(o)  
Pipeline Latency  
Digital Output  
Sample 1  
Sample 2  
NOTE A: All timing measurements are based on 50% of edge transition.  
Figure 2. Digital Output Timing Diagram  
8
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
TYPICAL CHARACTERISTICS  
POWER DISSIPATION  
vs  
SAMPLING FREQUENCY  
96  
94  
92  
90  
88  
86  
84  
82  
AV  
DD  
= DV  
= 3 V  
DD  
f = 3.5 MHz  
i
T
= 25°C  
A
5
10  
15  
20  
25  
30  
f
Sampling Frequency MHz  
s
Figure 3  
EFFECTIVE NUMBER OF BITS  
vs  
TEMPERATURE  
10.0  
9.5  
9.0  
8.5  
8.0  
7.5  
7
AV  
DD  
= DV  
= 3 V  
DD  
f = 3.5 MHz  
i
f
= 30 MSPS  
s
40  
15  
10  
35  
60  
85  
T
A
Temperature °C  
Figure 4  
9
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
TYPICAL CHARACTERISTICS  
EFFECTIVE NUMBER OF BITS  
vs  
SAMPLING FREQUENCY  
10.0  
9.5  
9.0  
8.5  
8.0  
7.5  
7
AV  
DD  
= DV  
= 3 V  
DD  
f = 3.5 MHz  
i
T
= 25°C  
A
5
10  
15  
20  
25  
30  
f
Sampling Frequency MSPS  
s
Figure 5  
EFFECTIVE NUMBER OF BITS  
vs  
SAMPLING FREQUENCY  
10.0  
9.5  
9.0  
8.5  
8.0  
7.5  
7
AV  
DD  
= 5 V,  
= 3 V  
DV  
DD  
f = 3.5 MHz  
i
A
T
= 25°C  
5
10  
15  
20  
25  
30  
f
Sampling Frequency MSPS  
s
Figure 6  
10  
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TYPICAL CHARACTERISTICS  
EFFECTIVE NUMBER OF BITS  
vs  
SAMPLING FREQUENCY  
10.00  
9.50  
9.00  
8.50  
8.00  
7.50  
7.00  
AV  
DD  
= DV = 5 V,  
DD  
f = 3.5 MHz  
i
T
= 25°C  
A
5
10  
15  
20  
25  
30  
f
Sampling Frequency MSPS  
s
Figure 7  
DIFFERENTIAL NONLINEARITY  
vs  
INPUT CODE  
1.0  
0.8  
0.6  
AV  
DD  
s
= 3 V, DV  
= 30 MSPS  
= 3 V  
DD  
f
0.4  
0.2  
0.0  
0.2  
0.4  
0.6  
0.8  
1  
0
128  
256  
384  
512  
640  
768  
896  
1024  
Input Code  
Figure 8  
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TYPICAL CHARACTERISTICS  
INTEGRAL NONLINEARITY  
vs  
INPUT CODE  
2.0  
1.5  
AV  
DD  
= 3 V  
= 3 V  
DV  
DD  
f
= 30 MSPS  
1.0  
s
0.5  
0.0  
0.5  
1.0  
1.5  
2.0  
0
128  
256  
384  
512  
640  
768  
896  
1024  
Input Code  
Figure 9  
FFT  
vs  
FREQUENCY  
0
20  
AV  
DD  
= 3 V  
= 3 V  
DV  
DD  
f = 3.5 MHz,  
i
40  
1 dBFS  
60  
80  
100  
120  
140  
0
0
20  
1.5  
40  
3
0
4.5  
0
6
00  
7.5  
10
9
40  
10.5  
10
12  
10
13.5  
00  
15  
f Frequency MHz  
Figure 10  
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CMOS ANALOG-TO-DIGITAL CONVERTER  
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PRINCIPLES OF OPERATION  
The analog input AIN is sampled in the sample-and-hold unit, the output of which goes to a programmable gain  
amplifier (PGA). The PGA feeds the ADC core, where the process of analog to digital conversion is performed  
against ADC reference voltages, REFTF and REFBF.  
Connecting the MODE pin to one of three voltages, AGND, AV  
or AV /2 sets up operating configurations.  
DD  
DD  
The three settings open or close internal switches to select one of the three basic methods of ADC reference  
generation.  
Depending on the users choice of operating configuration, the ADC reference voltages may come from the  
internal reference buffer (IRB) or may be fed from completely external sources. Where the reference buffer is  
employed, the user can choose to drive it from the onboard reference generator (ORG), or may use an external  
voltage source. A specific configuration is selected by connections to the REFSENSE, VREF, REFTS and  
REFBS, and REFTF and REFBF pins, along with any external voltage sources selected by the user.  
The THS1031 offers a clamp function for dc restoration of ac-coupled signals. The clamp voltage may be set  
digitally via the 10-bit clamp DAC or by the analog level applied to the CLAMPIN input.  
The ADC core drives out through output buffers to the I/O pins I/O0 to I/O9. The output buffers can be disabled  
by the OE pin. Control input data on I/O0 to I/O9 can then be written, by pulses on WR, to the control registers.  
These registers control clamp operation, output format (unsigned binary or twos complement), the PGA gain  
setting and the device power down function.  
A single-ended, sample-rate clock (30 MHz maximum) is required at pin CLK. The analog input signal is  
sampled on the rising edge of CLK, and corresponding data is output after the following third rising edge.  
The user-chosen operating configuration and reference voltages determine what input signal voltage range the  
THS1031 can handle.  
The following sections explain:  
Theinternalsignalflowofthedevice, andhowtheinputsignalspanisrelatedtotheADCreferencevoltages;  
The ways in which the ADC reference voltages can be buffered internally, or externally applied;  
How to set the onboard reference generator output, if required, and several examples of complete  
configurations.  
Subsequent sections explain the clamp function and digital controls, followed by more detailed application  
information.  
signal processing chain (sample and hold, PGA, ADC)  
Figure 11 shows the signal flow through the sample and hold unit and the PGA to the ADC core.  
REFTF  
VP+  
VQ+  
1
AIN  
REFTS  
REFBS  
Sample  
and  
Hold  
ADC  
Core  
1/2  
1/2  
PGA  
VP–  
VQ–  
REFBF  
Figure 11. Analog Input Signal Flow  
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PRINCIPLES OF OPERATION  
sample-and-hold  
The analog input signal A is applied to the AIN pin, either dc-coupled, ac-coupled, or ac-coupled with dc  
IN  
restoration using the THS1031 clamp circuit.  
The differential sample and hold processes A with respect to the voltages applied to the REFTS and REFBS  
IN  
pins, to give a differential output VP+ VP= VP given by:  
VP = A VM  
IN  
(1)  
Where:  
VM  
(REFTS REFBS)  
2
(2)  
For single-ended input signals, VM is a constant voltage; usually the AIN mid-scale input voltage. However if  
MODE = AV /2 then REFTS and REFBS can be connected together to operate with AIN as a complementary  
DD  
pair of differential inputs (see Figures 15 and 16).  
programmable gain amplifier  
+
VP is amplified by the PGA and fed into the ADC as a differential voltage VQ VQ = VQ  
VQ = Gain × VP = Gain × [A VM]  
IN  
The default PGA gain at power up is 1, but can be programmed from 0.5 to 4.0 via the control register.  
analog-to-digital converter  
In all operating configurations, VQ is digitized against ADC reference voltages REFTF and REFBF, full-scale  
values of VQ being given by  
(REFTF REFBF)  
VQFS  
2
(3)  
(REFTF REFBF)  
2
VQFS  
VQ voltages outside the range VQFSto VQFS+ lie outside the conversion range of the ADC. Attempts to  
convert out-of-range inputs are signalled to the application by driving the OVR output pin high. VQ voltages less  
than VQFSgive ADC output code 0. VQ voltages greater than VQFS+ give output code 1023.  
complete system  
Combining equations 1 to 3, the analog full-scale input voltages at AIN which give VQFS+ and VQFSat the  
PGA output are:  
(REFTF REFBF)  
A
FS  
VM  
IN  
(2 Gain)  
(4)  
and  
(REFTF REFBF)  
(2 Gain)  
A
FS  
VM  
IN  
(5)  
(6)  
The analog input span (voltage range) that lies within the ADC conversion range is:  
Input span [(FS (FS )] (REFTF REFBF) Gain  
)
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PRINCIPLES OF OPERATION  
complete system (continued)  
The REFTF and REFBF voltage difference and the gain sets the device input range. The next sections describe  
in detail the various methods available for setting voltages REFTF and REFBF to obtain the desired input span  
and device performance.  
ADC reference generation  
The THS1031 has three primary modes of ADC reference generation, selected by the voltage level applied to  
the MODE pin.  
Connecting the MODE pin to AGND gives full external reference mode. In this mode, the user supplies the ADC  
reference voltages directly to pins REFTF and REFBF. This mode is used where there is need for minimum  
power drain or where there are very tight tolerances on the ADC reference voltages. This mode also offers the  
possibility of Kelvin connection of the reference inputs to the THS1031 to eliminate any voltage drops from  
remote references that may occur in the system. Only single-ended input is possible in this mode.  
Connecting the MODE pin to AV /2 gives differential mode. In this mode, the ADC reference voltages REFTF  
DD  
and REFBF are generated by the internal reference buffer from the voltage applied to the VREF pin. This mode  
is suitable for handling differentially presented inputs, which are applied to the AIN and REFTS/REFBS pins.  
A special case of differential mode is center span mode, in which user applies a single-ended signal to AIN and  
applies the mid-scale input voltage (VM) to the REFTS and REFBS pins.  
Connecting the MODE pin to AV  
gives top/bottom mode. In this mode, the ADC reference voltages REFTF  
DD  
and REFBF are generated by the internal reference buffer from the voltages applied to the REFTS and REFBS  
pins. Only single-ended input is possible in top/bottom mode.  
Table 1. Typical Set of Reference Connections  
VREF  
VOLTAGE  
REFERENCE MODE  
MODE  
REFSENSE  
REFTS, REFBS  
ANALOG INPUT FIGURES  
Reference buffer powered  
down, reference voltage pro-  
vided directly by REFTS and  
REFBS  
External  
AV  
SS  
AV  
DD  
Disabled  
Single-ended  
12, 13, 14  
15, 16, 17  
VREF  
AGND  
1 V  
2 V  
Externally connect REFTS  
to REFBS. This pair then  
forms AINto the ADC.  
Differential or  
center span  
Internal  
AV /2  
DD  
External  
divider  
1 + Ra/Rb  
(see Figure 22)  
External (through internal  
reference buffer)  
AV  
DD  
Disabled  
REFTS = V  
+ (V  
Single-ended  
MID  
) × Gain/2  
FS+  
FS+  
V
FS–  
VREF  
AGND  
1 V  
2 V  
Output of VREF can be  
externally tied to REFTS or  
REFBS to provide one of the  
reference voltages  
AV  
DD  
18, 19  
REFBS = V  
MID  
(V  
(top-bottom  
mode)  
V ) × Gain/2  
FS–  
External  
divider  
1 + Ra/Rb  
(see Figure 22)  
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PRINCIPLES OF OPERATION  
full external reference mode (mode = AGND)  
REFTF  
1
AIN+  
REFTS  
REFBS  
Sample  
and  
Hold  
ADC  
Core  
1/2  
1/2  
PGA  
REFBF  
Internal  
Reference  
Buffer  
Figure 12. ADC Reference Generation, MODE = AGND  
When MODE is connected to AGND, the internal reference buffer is powered down, its inputs and outputs  
disconnected, and REFTS and REFBS internally connected to REFTF and REFBF respectively. These nodes  
are connected by the user to external sources to provide the ADC reference voltages. The internal connections  
are designed for use in kelvin connection mode (Figure 14). When using external reference mode as shown  
in Figure 13, REFTS must be shorted to REFTF and REFBS must be shorted to REFBF externally. The mean  
of REFTF and REFBF must be equal to AV /2 (see Figure 13).  
DD  
AV  
DD  
+FS  
AV  
DD  
AIN  
REFSENSE  
2
FS  
AV  
DD  
GAIN  
2
REFTS  
REFBS  
DC SOURCE =  
DC SOURCE =  
+ [(FS+) (FS)] ×  
2
AV  
DD  
GAIN  
2
[(FS+) (FS)] ×  
0.1 µF  
2
REFTF  
REFBF  
10 µF  
0.1 µF  
0.1 µF  
MODE  
Figure 13. Full External Reference Mode  
It is also possible to use REFTS and REFBS as sense lines to drive the REFTF and REFBF lines (Kelvin mode)  
to overcome any voltage drops within the system (see Figure 14).  
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PRINCIPLES OF OPERATION  
full external reference mode (mode = AGND) (continued)  
AV  
DD  
+FS  
AV  
DD  
AIN  
REFSENSE  
2
FS  
REFTS  
REFBS  
_
+
AV  
REFTF  
DD  
GAIN  
2
REFT =  
REFB =  
+ [(FS+) (FS)] ×  
[(FS+) (FS)] ×  
2
0.1 µF  
0.1 µF  
10 µF  
0.1 µF  
_
+
REFBF  
MODE  
AV  
DD  
GAIN  
2
2
Figure 14. Full External Reference With Kelvin Connections  
differential mode (mode = AV /2)  
DD  
AV  
DD  
+ VREF  
2
REFTF =  
1
AIN+  
REFTS  
REFBS  
Sample  
and  
Hold  
ADC  
Core  
1/2  
1/2  
PGA  
AIN–  
AV  
DD  
VREF  
Internal  
Reference  
Buffer  
VREF  
REFBF =  
2
AGND  
Figure 15. ADC Reference Generation, MODE = AV /2  
DD  
When MODE = AV /2, the internal reference buffer is enabled, its outputs internally switched to REFTF and  
DD  
REFBF and inputs internally switched to VREF and AGND as shown in Figure 15. The REFTF and REFBF  
voltages are centered on AV /2 by the internal reference buffer and the voltage difference between REFTF  
DD  
and REFBF equals the voltage at VREF. The internal REFTS to REFBS and REFTF to REFBF switches are  
open in this mode, allowing REFTS and REFBS to form the AINto the sample and hold.  
Depending on the connection of the REFSENSE pin, the voltage on VREF may be externally driven, or set to  
an internally generated voltage of 1 V, 2 V, or an intermediate voltage (see the onboard reference generator  
configuration).  
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PRINCIPLES OF OPERATION  
differential mode (mode = AV /2) (continued)  
DD  
AV  
DD  
+FS  
2
AIN+  
AIN  
MODE  
FS  
+FS  
REFTS  
AIN–  
FS  
REFBS REFSENSE  
0.1 µF  
REFTF  
REFBF  
VREF  
10 µF  
0.1 µF  
0.1 µF  
Figure 16. Differential Input Mode, 1-V Reference Span  
AV  
DD  
2
+FS  
VM  
FS  
AIN  
MODE  
REFTS  
DC SOURCE = VM  
+
_
VM  
REFBS  
REFTF  
0.1 µF  
0.1 µF  
10 µF  
0.1 µF  
REFBF  
REFSENSE  
Figure 17. Center Span Mode, 2-V Reference Span  
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PRINCIPLES OF OPERATION  
top/bottom mode (MODE = AV  
)
DD  
REFTF = AV  
DD  
+ (REFTS REFBS)  
2
1
AIN+  
REFTS  
REFBS  
Sample  
and  
Hold  
ADC  
Core  
1/2  
1/2  
PGA  
REFBF = AV  
(REFTS REFBS)  
Internal  
Reference  
Buffer  
DD  
2
Figure 18. ADC Reference Generation Mode = AV  
DD  
ConnectingMODEtoAV enablestheinternalreferencebuffer. ItsinputsareinternallyswitchedtotheREFTS  
DD  
and REFBS pins and its outputs internally switched to pins REFTF and REFBF. The internal connections  
(REFTS to REFTF) and (REFBS to REFBF) are broken.  
To match the signal span to the full ADC input span, the voltage difference between REFTS and REFBS should  
be REFTS REFBS = [(FS+) (FS)] × Gain, with the average of the REFTS and REFBS voltages being the  
AIN midscale voltage, VM.  
Typically, REFSENSE is tied to AV  
choose to use the ORG output to VREF as either REFTS or REFBS.  
to disable the ORG output to VREF (as in Figure 19), but the user can  
DD  
AV  
DD  
+FS  
AIN  
MODE  
FS  
GAIN  
DC SOURCE = VM + [(FS+) (FS)] ×  
REFSENSE  
REFTS  
REFBS  
2
GAIN  
2
DC SOURCE =VM [(FS+) (FS)] ×  
0.1 µF  
REFTF  
REFBF  
10 µF  
0.1 µF  
0.1 µF  
Figure 19. ADC Reference Generation Mode = AV  
DD  
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PRINCIPLES OF OPERATION  
onboard reference generator configuration  
The onboard reference generator (ORG) can supply a supply-voltage-independent and temperature-  
independent voltage on pin VREF.  
External connections to REFSENSE control the ORGs output to the VREF pin as shown in Table 2.  
Table 2. Effect of REFSENSE Connection on VREF Value  
REFSENSE CONNECTION  
VREF pin  
ORG OUTPUT TO VREF  
REFER TO:  
Figure 20  
Figure 21  
Figure 22  
Figure 23  
1 V  
2 V  
AGND  
External divider junction  
(1 + R /R )  
A B  
AV  
DD  
Open circuit  
REFSENSE = AV  
powers the ORG down, saving power when the ORG function is not required.  
DD  
If MODE = AV /2, the voltage on VREF determines the ADC reference voltages:  
DD  
AV  
DD  
VREF  
2
REFTF  
REFBF  
2
(7)  
AV  
DD VREF  
2
2
REFTF REFBF  
VREF  
Internal  
Reference  
Buffer  
Mode =  
AV  
DD  
2
+
_
VREF = 1 V  
REFSENSE  
+
VBG  
_
0.1 µF 1 µF  
Tantalum  
AGND  
Figure 20. 1-V VREF Using ORG  
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PRINCIPLES OF OPERATION  
onboard reference generator configuration (continued)  
Internal  
Reference  
Buffer  
Mode =  
AV  
DD  
2
+
_
VREF = 2 V  
REFSENSE  
+
_
VBG  
0.1 µF 1 µF  
Tantalum  
10 kΩ  
10 kΩ  
AGND  
Figure 21. 2-V VREF Using ORG  
Internal  
Reference  
Buffer  
Mode =  
AV  
DD  
2
+
_
VREF = 1 + (Ra/Rb)  
+
_
VBG  
0.1 µF 1 µF  
Tantalum  
Ra  
REFSENSE  
Rb  
AGND  
Figure 22. External Divider Mode  
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PRINCIPLES OF OPERATION  
onboard reference generator configuration (continued)  
Internal  
Reference  
Buffer  
Mode =  
AV  
DD  
2
VREF = External  
REFSENSE  
+
_
+
VBG  
_
AV  
DD  
AGND  
Figure 23. Drive VREF Mode  
operating configuration examples  
This section provides examples of operating configurations.  
Figure 24 shows the operating configuration in top/bottom mode for a 2-V span single-ended input, using VREF  
to drive REFTS and with PGA gain = 1. Connecting the MODE pin to AV  
puts the THS1031 in top/bottom  
DD  
mode. Connecting pin REFSENSE to AGND sets the output of the ORG to 2 V. REFTS and REFBS are  
user-connected to VREF and AGND respectively to match the AIN pin input range to the voltage range of the  
input signal.  
AV  
DD  
2 V  
1 V  
0 V  
AIN  
MODE  
VREF = 2 V  
REFTS  
0.1 µF  
0.1 µF  
REFTF  
REFBF  
REFSENSE  
REFBS  
10 µF  
0.1 µF  
Figure 24. Operation Configuration in Top/Bottom Mode  
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PRINCIPLES OF OPERATION  
operating configuration examples (continued)  
In Figure 25, the input signal is differential, soMode=AV /2(differentialmode)issettoallowtheinversesignal  
DD  
to be applied to REFTS and REFBS. The differential input goes from 0.8 V to 0.8 V, giving a total input signal  
span of 1.6 V. Using a PGA gain of 1, REFTFREFBF should therefore, equal 1.6 V. REFSENSE is connected  
to resistors RA and RB (external divider mode) to make VREF = 1.6 V, that is R /R = 0.6 (see Figure 22).  
A
B
AV  
DD  
2
1.4 V  
1 V  
AIN+  
AIN  
MODE  
0.6 V  
1.4 V  
1 V  
REFTS  
AIN–  
VREF = 1.6 V  
REFSENSE  
0.6 V  
REFBS  
REFTF  
R
A
B
0.1 µF  
0.1 µF  
R
10 µF  
0.1 µF  
REFBF  
Figure 25. Differential Operation  
Figure 26 shows a center span configuration for an input waveform swinging between 0.2 and 1.9 V. Pins  
REFTS and REFBS are connected to a voltage source of 1.05 V, equal to the mid-scale of the input waveform.  
With the PGA gain set to its default value of 1, REFTFREFBF should be set equal to the span of the input  
waveform, 1.7 V, so VREF is connected to an external source of 1.7 V. REFSENSE must be connected to AV  
to disable the ORG output to VREF (see Figure 23) to allow this external source to be applied.  
DD  
AV  
DD  
AV  
DD  
2
1.9 V  
1.05 V  
0.2 V  
AIN  
MODE  
REFSENSE  
REFTS  
DC SOURCE = 1.05 V  
REFBS  
REFTF  
0.1 µF  
VREF  
DC SOURCE = 1.7 V  
10 µF  
0.1 µF  
0.1 µF  
REFBF  
Figure 26. Center Span Operation  
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PRINCIPLES OF OPERATION  
operating configuration examples (continued)  
Figure 27 shows an example of top/bottom mode operation on an input span of 800 mV with mid-scale value  
1.5 V. Pin REFTS is set to 2.5 V and pin REFBS to 0.5 V, making their average value equal to the mid-scale  
value of A and giving the maximum specified difference of 2 V between REFTS and REFBS to maximize the  
IN  
full-scale range of the ADC core for best resolution. The PGA gain then has to be set to 2.5, to amplify the  
800 mV input signal to 2 V at the ADC core input.  
PP  
PP  
AV  
DD  
1.9 V  
1.5 V  
1.1 V  
AIN  
MODE  
REFSENSE  
REFTS  
DC SOURCE = 2.5 V  
DC SOURCE = 0.5 V  
REFBS  
REFTF  
0.1 µF  
10 µF  
0.1 µF  
0.1 µF  
REFBF  
Figure 27. Top/Bottom Mode, PGA Gain 2.5  
clamp operation  
10-Bit  
DAC  
CLAMPIN  
CLAMP  
Control Register (Bit CLINT)  
(Clamp)  
+
_
V
C
SW1  
IN  
R
IN  
AIN  
S/H  
V
IN  
Figure 28. Schematic of Clamp Circuitry  
The THS1031 provides a clamp function for restoring a dc reference level to the signal at AIN which has been  
lost through ac-coupling from the signal source to this pin.  
Figure 29 shows an example of using the clamp to restore the black level of a composite video input ac coupled  
to AIN. While the clamp pin is held high, the clamp amplifier forces the voltage at AIN to equal the clamp  
reference voltage, setting the dc voltage at AIN for the video black level.  
After power up, the clamp reference voltage is the voltage on the CLAMPIN pin. This reference can instead be  
taken from the internal CLAMP DAC by suitably programming the THS1031 clamp and control registers.  
Clamp acquisition and clamp droop design calculations are discussed later.  
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CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
PRINCIPLES OF OPERATION  
clamp operation (continued)  
Line Sync  
Black  
Level  
Video at AIN  
CLAMP  
Figure 29. Example Waveforms for Line-Clamping to a Video Input Black Level  
clamp DAC output voltage range and limits  
When using the internal clamp DAC in top/bottom or center span mode, the user must ensure that the desired  
dc clamp level at AIN lies within the voltage range V to V . This is because the clamp DAC voltage  
REFBF  
REFTF  
REFTF  
is constrained to lie within this range V  
to V  
. Specifically:  
REFBF  
VDAC  
V
(V  
V
)
(0.006 0.988 (DAC code) 1024)  
REFBF  
REFTF  
REFBF  
(8)  
DAC codes can range from 0 to 1023. Figure 30 graphically shows the clamp DAC output voltage versus the  
DAC code.  
VDAC  
V
REFTF  
V
+ 0.006(V )  
V  
REFBF  
REFTF REFBF  
V
+ 0.987(V )  
V  
REFBF  
REFTF REFBF  
V
REFBF  
DAC Code  
0
1023  
Figure 30. Clamp DAC Output Voltage Versus DAC Register Code Value  
If the desired dc level at AIN does not lie within the voltage range V to V , then either the CLAMPIN  
REFTF  
REFBF  
pin can be used instead to provide a suitable reference voltage, or it may be possible to redesign the application  
to move the AIN input range into the CLAMP DAC voltage range. This is achieved in both top/bottom and center  
span modes by shifting both REFTS and REFBS up or down by the voltage through which the AIN input range  
is to be moved.  
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CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
PRINCIPLES OF OPERATION  
power management  
In power-sensitive applications (such as battery-powered systems) where the THS1031 ADC is not required  
to convert continuously, power can be saved between conversion intervals by placing the THS1031 into  
power-down mode. This is achieved by setting bit 3 (PWDN) of the control register to 1. In power-down mode,  
the device typically consumes less than 1 mW of power in either top/bottom or center-span modes. Power-down  
mode is exited by resetting control register bit 3 to 0. On power up, the THS1031 typically requires 5 ms of  
wake-up time before valid conversion results are available.  
In systems where the ADC must run continuously, but where the clamp is not required, setting control register  
bit 6 (CLDIS to 1), which disables only the clamp circuits, can save power.  
Disabling the ORG in applications where the ORG output is not required can also reduce power dissipation by  
1 mA analog I . This is achieved by connecting the REFSENSE pin to AV  
.
DD  
DD  
output format and digital I/O  
While the OE pin is held low, ADC conversion results are output at pins I/O0 (LSB) to I/O9 (MSB). The ADC input  
over-range indicator is output at pin OVR. OVR is also disabled when OE is held high.  
The default ADC output data format is unsigned binary (output codes 0 to 1023). The output format can be  
switched to 2s complement (output codes 512 to 511) by setting control register bit 5 (TWOC) to 1.  
writing to the internal registers through the digital I/O bus  
Pulling pin OE high disables the I/O and OVR pin output drivers, placing the driver outputs in a high impedance  
state. This allows control register data to be loaded into the THS1031 by presenting it on the I/O0 to I/O9 pins  
and pulsing the WR pin high to latch the data into the chosen control or DAC register.  
Figure 31 shows an example register write cycle where the clamp DAC code is set to 10F (hex) by writing to  
clamp registers 1 and 2 (see the register map in Table 3). Pins I/O0 to I/O7 are driven to the clamp DAC code  
lower byte (0F hex) and pins I/08 and I/O9 are both driven to 0 to select clamp register 1 as the data destination.  
The clamp low-byte data is then loaded into this register by pulsing WR high. The top 2 bits of the DAC word  
are then loaded by driving 01(hex) on pins I/O0 to I/O7 and by driving pin I/O8 to 1 and pin I/O9 to 0 to select  
clamp register 2 as the data destination. WR is pulsed a second time to latch this second control word into clamp  
register 2. Interface timing parameters are given in Figures 1 and 2.  
OE  
WR  
Output  
Input 00F  
Input 101  
Output  
I/O (09)  
Load 0F Into  
REGISTER 0  
Load 01 Into  
REGISTER 1  
Figure 31. Example Register Write Cycle to Clamp DAC Register  
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PRINCIPLES OF OPERATION  
digital control registers  
The THS1031 contains two clamp registers and a control register for user programming of THS1031 operation.  
Binary data can be written into these registers by using pins I/O0 to I/O9 and the WR and OE pins (see the  
previous section). In input mode, the two I/O bus MSBs are address bits, 00 addressing clamp register 1, 01  
clamp register 2, and 10 the control register.  
Table 3. Register Map  
BIT  
ADDRESS  
I/O[9:8]  
DEF  
(HEX)  
DESCRIPTION  
B7  
B6  
B5  
B4  
B3  
B2  
B1  
B0  
00  
01  
10  
11  
Clamp Reg. 1  
Clamp Reg. 2  
Control Reg.  
Reserved  
00  
00  
01  
DAC[7]  
DAC[6]  
DAC[5]  
DAC[4]  
DAC[3]  
DAC[2]  
DAC[1]  
DAC[9]  
PGA[1]  
DAC[0]  
DAC[8]  
PGA[0]  
CLDIS  
TWOC  
CLINT  
PDWN  
PGA[2]  
Table 4. Register Contents  
REGISTER  
BIT NO BIT NAME(S)  
DEFAULT  
DESCRIPTION  
PGA gain:  
000 = 0.5  
001 = 1.0 (default value)  
010 = 1.5  
2:0  
PGA[2:0]  
0
011 = 2.0  
100 = 2.5  
101 = 3.0  
110 = 3.5  
111 = 4.0  
Power down  
3
4
5
PDWN  
CLINT  
TWOC  
CLDIS  
0
0
0
0
0 = THS1031 powered up  
1 = THS1031 powered down  
Control Register  
I/O[9:8] = 10  
Clamp voltage internal/external  
0 = external analog clamp voltage from CLAMPIN pin  
1 = from onboard DAC (see clamp register)  
Output format  
0 = unsigned binary  
1 = twos complement  
Clamp amplifier disable (for power saving)  
0 = Enable  
1 = Disable  
6
7
Unused  
Clamp DAC voltage  
Clamp Register 1  
I/O[9:8] = 00  
(DAC[0] = LSB.)  
DAC[9:0] = 00h: Clamp voltage = REFBF  
DAC[9:0] = 3Fh: Clamp voltage = REFTF  
7:0  
DAC[7:0]  
DAC[9:8]  
0
0
7:2  
1:0  
Unused  
Clamp Register 2  
I/O[9:8] = 01  
Clamp DAC voltage  
(DAC[9] = MSB)  
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PRINCIPLES OF OPERATION  
driving the THS1301 analog inputs  
driving AIN  
Figure 32 shows an equivalent circuit for the THS1031 AIN pin. The load presented to the system at the AIN  
pin comprises the switched input sampling capacitor, C  
, and various stray capacitances, C and C  
.
SAMPLE  
P1  
P2  
AV  
DD  
CLK  
1.2 pF  
AIN  
C
C1  
8 pF  
C2  
1.2 pF  
SAMPLE  
AGND  
CLK  
+
_
V
LAST  
Figure 32. Equivalent Circuit of Analog Input AIN  
In any single-ended input mode, V = the average of the previously sampled voltage at AIN and the average  
LAST  
of the voltages on pins REFTS and REFBS. In any differential mode, V  
= the common mode input voltage.  
LAST  
The external source driving AIN must be able to charge and settle into C  
to within 0.5 LSB error while sampling (CLK pin low) to achieve full ADC resolution.  
and the C and C strays  
P1 P2  
SAMPLE  
AIN input current and input load modeling  
When CLK goes low, the source driving AIN must charge the total switched capacitance C = C  
S
The total charge transferred depends on the voltage at AIN and is given by  
+ C  
.
SAMPLE  
P2  
Q
(AIN  
V
)
C .  
CHARGING  
LAST  
S
(9)  
do not change between samples, the maximum amount of  
For a fixed voltage at AIN, so that AIN and V  
charge transfer occurs at AIN = FS(charging current flows out of THS1030) and AIN = FS+ (current flows into  
LAST  
THS1030). If AIN is held at the voltage FS+, VLAST = [(FS+) + VM]/2, giving a maximum transferred charge:  
[(FS  
)
VM]  
C
(FS  
)
[(FS  
2
)
VM]  
S
Q(FS)  
C
S
2
(10)  
(1 4 of the input voltage span)  
C
S
If the input voltage changes between samples, then the maximum possible charge transfer is  
Q(max) Q(FS)  
which occurs for a full-scale input change (FS+ to FSor FSto FS+) between samples.  
3
(11)  
The charging current pulses can make the AIN source jump or ring, especially if the source is slightly inductive  
at high frequencies. Inserting a small series resistor of 20 or less in the input path can damp source ringing.  
See Figure 33. This resistor can be made larger than 20 if reduced input bandwidth or distortion performance  
is acceptable.  
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PRINCIPLES OF OPERATION  
AIN input current and input load modeling (continued)  
R< 20 Ω  
AIN  
V
S
Figure 33. Damping Source Ringing Using a Small Resistor  
equivalent input resistance at AIN and ac-coupling to AIN  
Some applications may require ac-coupling of the input signal to the AIN pin. Such applications can use an  
ac-coupling network such as shown in Figure 34.  
AV  
DD  
R
(Bias1)  
C
in  
AIN  
R
(Bias2)  
Figure 34. AC-Coupling the Input Signal to the AIN Pin  
Note that if the bias voltage is derived from the supplies, as shown in Figure 34, then additional filtering should  
be used to ensure that noise from the supplies does not reach AIN.  
Working with the input current pulse equations given in the previous section is awkward when designing  
ac-coupling input networks. For such design, it is much simpler to model the AIN input as an equivalent  
resistance, R  
, from the AIN pin to a voltage source VM where  
AIN  
VM = (REFTS + REFBS)/2 and R  
= 1 / (C x f  
)
clk  
AIN  
S
where f is the CLK frequency.  
clk  
The high-pass 3 dB cutoff frequency for the circuit shown in Figure 34 is:  
1
f
(
3 dB)  
2
R
tot  
IN  
(12)  
where R tot is the parallel combination of Rbias1, Rbias2, and R  
. This approximation is good provided that  
IN  
AIN  
the clock frequency, f , is much higher than f(3 dB).  
clk  
Note also that the effect of the equivalent R  
bias network dc level.  
and VM at the AIN pin must be allowed for when designing the  
AIN  
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CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
PRINCIPLES OF OPERATION  
details  
The above value for R  
is derived by noting that the average AIN voltage must equal the bias voltage supplied  
AIN  
by the ac coupling network. The average value of V  
in equation 13 is thus a constant voltage  
LAST  
V
= V(AIN bias) VM  
LAST  
(13)  
For an input voltage V at the AIN pin,  
in  
Qin = (V V  
) × C  
S
IN  
LAST  
(14)  
Provided that f (3 dB) is much lower than f , a constant current flowing over the clock period can approximate  
clk  
the input charging pulse  
I
= Qin/t  
clk  
clk  
= (Vin V  
IN  
= Qin × f  
) × C × f  
S clk  
LAST  
(15)  
The ac input resistance R  
is then  
AIN  
R
= dIin/dVin  
AIN  
= 1 / (dVin / dIin)  
= 1 / (C x f  
)
clk  
S
(16)  
driving the VREF pin (differential mode)  
Figure 35 shows the equivalent load on the VREF pin when driving the internal reference buffer via this pin  
(MODE = AV /2 and REFSENSE = AV ).  
DD  
DD  
AV  
DD  
R
IN  
REFSENSE = AV  
DD  
,
VREF  
AV  
DD  
2
14 kΩ  
Mode =  
AGND  
+
AV  
DD  
4
+ VREF/4  
4
_
Figure 35. Equivalent Circuit of VREF  
The current flowing into I is given by  
IN  
I
(3 VREF AV  
)
IN  
DD  
(4  
R
)
IN  
(17)  
Note that the actual IIN may differ from this value by up to 50% due to device-to-device processing variations  
and allowing for operating temperature variations.  
The user should ensure that VREF is driven from a low noise, low drift source, well-decoupled to analog ground  
and capable of driving I .  
IN  
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PRINCIPLES OF OPERATION  
driving the internal reference buffer (top/bottom mode)  
Figure 36 shows the load present on the REFTS and REFBS pins in top/bottom mode due to the internal  
reference buffer only. The sample and hold must also be driven via these pins, which adds additional load.  
AV  
DD  
R
IN  
REFTS  
REFBS  
14 kΩ  
AV  
DD  
2
Mode =  
AGND  
+
_
AV  
DD  
+ REFTS + REFBS  
4
Figure 36. Equivalent Circuit of Inputs to Internal Reference Buffer  
Equations for the currents flowing into REFTS and REFBS are:  
(3 REFTS AV  
REFBS)  
DD  
)
I
I
TS  
IN  
IN  
(4  
R
IN  
(18)  
(3 REFBS AV  
REFTS)  
DD  
)
BS  
(4  
R
IN  
ThesecurrentsmustbeprovidedbythesourcesonREFTSandREFBSinadditiontotherequirementsofdriving  
the sample and hold. Tolerance on these currents are ±50%.  
driving REFTS and REFBS  
AV  
DD  
CLK  
0.6 pF  
REFTS  
REFBS  
C
C1  
7 pF  
C2  
0.6 pF  
SAMPLE  
AGND  
Mode = AV  
DD  
CLK  
+
_
V
LAST  
Internal  
Reference  
Buffer  
Figure 37. Equivalent Circuit of REFTS and REFBS Inputs  
This is essentially a combination of driving the ADC internal reference buffer (if in top/bottom mode) and also  
drivingaswitchedcapacitorloadlikeAIN, butwiththesamplingcapacitorandC oneachpinnowbeing0.6 pF  
P2  
and about 0.6 pF respectively.  
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PRINCIPLES OF OPERATION  
driving REFTF and REFBF (full external reference mode)  
AV  
DD  
REFTF  
To REFBS  
(For Kelvin Connection)  
AGND  
680 Ω  
AV  
DD  
REFBF  
To REFTS  
(For Kelvin Connection)  
AGND  
Figure 38. Equivalent Circuit of REFTF and REFBF Inputs  
Note the need for off-chip decoupling.  
clamp operation  
The clamp voltage output level may be established by an analog voltage on the CLAMPIN pin or by  
programming the on-chip clamp DAC.  
clamp acquisition time  
Figure 39 shows the basic operation of the clamp circuit with the analog input AIN coupled via an RC circuit.  
10-Bit  
DAC  
CLAMPIN  
CLAMP  
Control Register  
+
V
CLAMP  
_
C
SW1  
IN  
R
IN  
AIN  
S/H  
V
IN  
Figure 39. Schematic of Clamp Circuitry  
After powerup, the clamp circuit requires SW1 to be closed to charge the coupling capacitor, C , to the voltage  
IN  
required to set the dc clamp level at AIN. The charging time required to set the correct clamp voltage is called  
the clamp acquisition time, t  
:
ACQ  
Vc  
Ve  
t
C
R
In  
ACQ  
IN  
IN  
(19)  
Vcisthedifferencebetweenthedcbiasvoltageleveloftheinputsignal, V , andthetargetclampoutputvoltage,  
IN  
V
. Ve is the difference between the ideal Vc and the actual Vc obtained during the acquisition time. The  
(clamp)  
maximum tolerable error depends on the application requirements.  
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PRINCIPLES OF OPERATION  
clamp acquisition time (continued)  
For example, consider clamping an incoming video signal that has a black level near 0.3 V to a black level of  
1.3 V at the THS1031 input. The voltage Vc required across the input coupling capacitor is thus 1.3 0.3 = 1 V.  
If a 10 mV or less clamp voltage error Ve will give acceptable system operation, if the source resistance Rin is  
20 and the coupling capacitor C is 1 µF, then the total clamp pulse duration required to reach this error is:  
IN  
Vc  
Ve  
1
0.01  
t
C
R
In  
1
F
20  
In  
= 92 µs (approximately)  
ACQ  
IN  
IN  
(20)  
Note that SW1 does not have to be closed continuously until the desired clamp voltage is achieved. The clamp  
level can be acquired over a longer interval by using a series of shorter clamp pulses with total pulse duration  
at least equal to the acquisition time calculated using equation 19.  
droop  
The charge pulses entering or leaving AIN caused by the sample and hold switched capacitor input can charge  
or discharge C , causing the voltage at AIN to drift toward VM (the average of REFTS and REFBS) during the  
IN  
time between clamp pulses. This effect is called clamp droop and can be seen as a slow change in the ADC  
output code when the input signal is a constant dc level. Through careful clamp circuit design, this droop can  
be kept below 1 LSB, giving no change in the ADC output between clamp pulses.  
The clamp voltage droop is a function of the input current to the THS1031 and the time between clamp pulses,  
td  
I
IN  
V
td (approximately)  
DROOP  
C
IN  
(21)  
Where:  
I
(V  
VM)  
VM)  
2
R
IN  
AIN  
AIN  
(V  
CS fclk  
2
AIN  
R
is the input resistance given by equation 20. Cs is approximately 2.5 pF. Substituting I into the droop  
IN  
AIN  
voltage equation gives  
V
(V VM)  
CS td (2 C )  
DROOP  
AIN  
IN  
(22)  
Note that I has maximum value when V  
level is near either full-scale input voltage. There is no droop when the clamp level equals VM because I is  
is either +FS or FS, and so the droop rate is worst then the clamp  
IN  
AIN  
IN  
zero. Note that the actual voltage droop may be up to 50% more than given by equation 22 when allowing for  
temperature variations and device to device processing variations.  
For example, with C = 1 µF at f = 30 MSPS conversion rate in top/bottom mode with REFTS = 2.5 V and  
IN  
clk  
REFBS = 0.5 V, the clamp droop over td = 63.5 ms when V  
= +FS is  
AIN  
V
(V  
VM)  
CS fclk td (2 C )  
DROOP  
AIN  
IN  
(2.5 V 1.5 V)  
2.5 pF 30 MMz 2  
0.0024 mV  
1.25 LSB (assuming PGA gain  
1)  
(23)  
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PRINCIPLES OF OPERATION  
clamp operation (continued)  
Thus if a constant voltage is applied to the clamp input that drives the ADC output to code 1023 (with no  
over-range), then the ADC output code will slowly drop to code 1022, or possibly code 1021, over the period  
t .  
d
If the calculated droop is greater than can be tolerated in the application then increase C to slow the droop  
IN  
and hence reduce the voltage change between clamp pulses.  
If a high leakage capacitor is used for coupling the input source to the AIN pin then the droop may be significantly  
larger than calculated above due to the capacitors rapid rate of self-discharge. Avoid using electrolytic and  
tantalum coupling capacitors as these usually exhibit much higher leakage then nonpolarized capacitor types.  
Electrolytic and tantalum capacitors also tend to have higher parasitics inductance, which can cause further  
problems at high input frequencies.  
steady-state clamp voltage error  
Under steady-state conditions, the change in the clamp voltage caused during clamping must equal the change  
caused by clamp droop, otherwise the effect causing the largest voltage change would pull the clamp voltage  
away until these charging and droop effects equalize.  
Figure 40 shows the approximate voltage waveform at AIN resulting from clamp droop during t and clamp  
d
voltage reacquisition during the clamp pulse time, t .  
c
V
(Clamp)  
V
COS  
V
= V  
AIN  
DROOP  
V
AIN  
t
t
d
c
VM  
Figure 40. Approximate Waveforms at AIN During Droop and Clamping  
The voltage change at AIN during acquisition has been approximated as a linear charging ramp by assuming  
that almost all of V  
approximationwhenV  
is then  
appears across R , giving a charging current V  
/Rin (this is a reasonable  
COS  
IN  
COS  
islargeenoughtobeaproblem).ThevoltagechangeatAINduringclampacquisition  
COS  
V
COS  
V
tc  
AIN  
R
(24)  
IN  
The peak-to-peak voltage variation at AIN must equal the clamp droop voltage at steady state. Equating the  
droop voltage to the clamp acquisition voltage change gives  
R
I
td  
IN  
IN  
tc  
V
COS  
(25)  
Where I is the input current given by equation, thus for low offset voltage, keep R low and ensure that the  
IN  
IN  
ratio t /t is not unreasonably large.  
d c  
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PRINCIPLES OF OPERATION  
driving the clock input  
Obtaining good performance from the THS1031 requires care when driving the clock input.  
Different sections of the sample-and-hold and ADC operate while the clock is low or high. The user should  
ensure that the clock duty cycle remains near 50% to ensure that all internal circuits have as much time as  
possible in which to operate.  
The CLK pin should be driven from a low jitter source for best dynamic performance. To maintain low jitter at  
the CLK input, any clock buffers external to the THS1031 should have fast rising edges. Use a fast logic family  
such as AC or ACT to drive the CLK pin, and consider powering any clock buffers separately from any other  
logic on the PCB to prevent digital supply noise appearing on the buffered clock edges as jitter.  
The CLK input threshold is nominally aroundAV /2ensurethatanyclockbuffershaveanappropriatesupply  
DD  
voltage to drive above and below this level.  
digital output loading and circuit board layout  
The THS1031 outputs are capable of driving rail-to-rail with up to 20 pF of load per pin at 30 MHz clock and 3 V  
digital supply. Minimizing the load on the outputs will improve THS1031 signal-to-noise performance by  
reducing the switching noise coupling from the THS1031 output buffers to the internal analog circuits. The  
output load capacitance can be minimized by buffering the THS1031 digital outputs with a low input capacitance  
buffer placed as close to the output pins as physically possible, and by using the shortest possible tracks  
between the THS1031 and this buffer.  
Noise levels at the output buffers, and hence coupling to the analog circuits within THS1031, becomes worse  
as the THS1031 digital supply voltage is increased. Where possible, consider using the lowest DV  
application can tolerate.  
that the  
DD  
Use good layout practices when designing the application PCB to ensure that any off-chip return currents from  
the THS1031 digital outputs (and any other digital circuits on the PCB) do not return via the supplies to any  
sensitive analog circuits. The THS1031 should be soldered directly to the PCB for best performance. Socketing  
the device will degrade performance by adding parasitic socket inductance and capacitance to all pins.  
user tips for obtaining best performance from the THS1031  
Voltages on AIN, REFTF and REFBF and REFTS and REFBS must all be inside the supply rails.  
ORG modes offer the simplest configurations for ADC reference generation.  
Choose differential input mode for best distortion performance.  
Choose a 2-V ADC input span for best noise performance.  
Choose a 1-V ADC input span for best distortion performance.  
If the ORG is not used to provide ADC reference voltages, its output may be used for other purposes in the  
system. Care should be taken to ensure noise is not injected into the THS1031.  
Use external voltage sources for ADC reference generation where there are stringent requirements on  
accuracy and drift.  
Drive clock input CLK from a low-jitter, fast logic stage, with a well-decoupled power supply and short PCB  
traces.  
35  
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
MECHANICAL DATA  
DW (R-PDSO-G**)  
PLASTIC SMALL-OUTLINE  
16 PINS SHOWN  
0.050 (1,27)  
16  
0.020 (0,51)  
0.014 (0,35)  
0.010 (0,25)  
M
9
0.419 (10,65)  
0.400 (10,15)  
0.010 (0,25) NOM  
0.299 (7,59)  
0.293 (7,45)  
Gage Plane  
0.010 (0,25)  
1
8
0°8°  
0.050 (1,27)  
0.016 (0,40)  
A
Seating Plane  
0.004 (0,10)  
0.012 (0,30)  
0.004 (0,10)  
0.104 (2,65) MAX  
PINS **  
16  
20  
24  
28  
DIM  
0.410  
0.510  
0.610  
0.710  
A MAX  
A MIN  
(10,41) (12,95) (15,49) (18,03)  
0.400  
0.500  
0.600  
0.700  
(10,16) (12,70) (15,24) (17,78)  
4040000/C 07/96  
NOTES: A. All linear dimensions are in inches (millimeters).  
B. This drawing is subject to change without notice.  
C. Body dimensions do not include mold flash or protrusion not to exceed 0.006 (0,15).  
D. Falls within JEDEC MS-013  
36  
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
THS1031  
3-V TO 5.5-V, 10-BIT, 30 MSPS  
CMOS ANALOG-TO-DIGITAL CONVERTER  
SLAS242E NOVEMBER 1999 REVISED MARCH 2002  
MECHANICAL DATA  
PW (R-PDSO-G**)  
PLASTIC SMALL-OUTLINE  
14 PINS SHOWN  
0,30  
0,19  
M
0,10  
0,65  
14  
8
0,15 NOM  
4,50  
4,30  
6,60  
6,20  
Gage Plane  
0,25  
1
7
0°8°  
A
0,75  
0,50  
Seating Plane  
0,10  
0,15  
0,05  
1,20 MAX  
PINS **  
8
14  
16  
20  
24  
28  
DIM  
3,10  
2,90  
5,10  
4,90  
5,10  
4,90  
6,60  
6,40  
7,90  
7,70  
9,80  
9,60  
A MAX  
A MIN  
4040064/F 01/97  
NOTES: A. All linear dimensions are in millimeters.  
B. This drawing is subject to change without notice.  
C. Body dimensions do not include mold flash or protrusion not to exceed 0,15.  
D. Falls within JEDEC MO-153  
37  
POST OFFICE BOX 655303 DALLAS, TEXAS 75265  
PACKAGE OPTION ADDENDUM  
www.ti.com  
17-Jun-2009  
PACKAGING INFORMATION  
Orderable Device  
THS1031CDW  
Status (1)  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
Package Package  
Pins Package Eco Plan (2) Lead/Ball Finish MSL Peak Temp (3)  
Qty  
Type  
Drawing  
SOIC  
DW  
28  
28  
28  
28  
28  
28  
28  
28  
28  
28  
20 Green (RoHS & CU NIPDAU Level-1-260C-UNLIM  
no Sb/Br)  
THS1031CDWG4  
THS1031CPW  
SOIC  
TSSOP  
TSSOP  
TSSOP  
TSSOP  
SOIC  
DW  
PW  
PW  
PW  
PW  
DW  
DW  
PW  
PW  
20 Green (RoHS & CU NIPDAU Level-1-260C-UNLIM  
no Sb/Br)  
50 Green (RoHS & CU NIPDAU Level-1-260C-UNLIM  
no Sb/Br)  
THS1031CPWG4  
THS1031CPWR  
THS1031CPWRG4  
THS1031IDW  
50 Green (RoHS & CU NIPDAU Level-1-260C-UNLIM  
no Sb/Br)  
2000 Green (RoHS & CU NIPDAU Level-1-260C-UNLIM  
no Sb/Br)  
2000 Green (RoHS & CU NIPDAU Level-1-260C-UNLIM  
no Sb/Br)  
20 Green (RoHS & CU NIPDAU Level-1-260C-UNLIM  
no Sb/Br)  
THS1031IDWG4  
THS1031IPW  
SOIC  
20 Green (RoHS & CU NIPDAU Level-1-260C-UNLIM  
no Sb/Br)  
TSSOP  
TSSOP  
50 Green (RoHS & CU NIPDAU Level-1-260C-UNLIM  
no Sb/Br)  
THS1031IPWG4  
50 Green (RoHS & CU NIPDAU Level-1-260C-UNLIM  
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 MATERIALS INFORMATION  
www.ti.com  
11-Mar-2008  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0 (mm)  
B0 (mm)  
K0 (mm)  
P1  
W
Pin1  
Diameter Width  
(mm) W1 (mm)  
(mm) (mm) Quadrant  
THS1031CPWR  
TSSOP  
PW  
28  
2000  
330.0  
16.4  
6.9  
10.2  
1.8  
12.0  
16.0  
Q1  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
11-Mar-2008  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
TSSOP PW 28  
SPQ  
Length (mm) Width (mm) Height (mm)  
346.0 346.0 33.0  
THS1031CPWR  
2000  
Pack Materials-Page 2  
IMPORTANT NOTICE  
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements,  
and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should  
obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are  
sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment.  
TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standard  
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mandated by government requirements, testing of all parameters of each product is not necessarily performed.  
TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and  
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Copyright © 2009, Texas Instruments Incorporated  

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