ADC122S625 [TI]

双路 12 位、50 kSPS 至 200 kSPS、同步采样模数转换器;
ADC122S625
型号: ADC122S625
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

双路 12 位、50 kSPS 至 200 kSPS、同步采样模数转换器

转换器 模数转换器
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ADC122S625  
www.ti.com  
SNAS451A FEBRUARY 2008REVISED MARCH 2013  
ADC122S625 Dual 12-Bit, 50 kSPS to 200 kSPS, Simultaneous Sampling A/D Converter  
Check for Samples: ADC122S625  
1
FEATURES  
DESCRIPTION  
The ADC122S625 is a dual 12-bit, 50 kSPS to 200  
kSPS simultaneous sampling Analog-to-Digital (A/D)  
converter. The analog inputs on both channels are  
sampled simultaneously to preserve their relative  
phase information to each other. The converter is  
23  
True Simultaneous Sampling Differential  
Inputs  
Specified Performance from 50 kSPS to 200  
kSPS  
based on  
a
successive-approximation register  
External Reference  
architecture where the differential nature of the  
analog inputs is maintained from the internal track-  
and-hold circuits throughout the A/D converter to  
provide excellent common-mode signal rejection. The  
ADC122S625 features an external reference that can  
be varied from 1.0V to VA.  
Wide Input Common-Mode Voltage Range  
Single High-Speed Serial Data Output  
Operating Temperature Range of 40°C to  
+105°C  
SPI™/ QSPI™/MICROWIRE/DSP Compatible  
Serial Interface  
The ADC122S625's serial data output is binary 2's  
complement and is compatible with several  
standards, such as SPI™, QSPI™, MICROWIRE™,  
and many common DSP serial interfaces. The serial  
clock (SCLK) and chip select bar (CS) are shared by  
both channels.  
APPLICATIONS  
Motor Control  
Power Meters/Monitors  
Multi-Axis Positioning Systems  
Instrumentation and Control Systems  
Data Acquisition Systems  
Medical Instruments  
Operating from a single 5V analog supply and a  
reference voltage of 2.5V, the total power  
consumption while operating at 200 kSPS is typically  
8.6 mW. With the ADC122S625 operating in power-  
down mode, the power consumption reduces to 2.6  
µW. The differential input, low power consumption,  
and small size make the ADC122S625 ideal for direct  
connection to sensors in motor control applications.  
Direct Sensor Interface  
KEY SPECIFICATIONS  
Conversion Rate: 50 kSPS to 200 kSPS  
INL: ±1 LSB (max)  
Operation is specified over the industrial temperature  
range of 40°C to +105°C and clock rates of 1.6 MHz  
to 6.4 MHz. The ADC122S625 is available in a 10-  
lead VSSOP package.  
DNL: ±0.95 LSB (max)  
SNR: 71 dBc (min)  
Connection Diagram  
THD: -72 dBc (min)  
ENOB: 11.25 bits (min)  
Power Consumption at 200 kSPS  
V
10  
9
CS  
1
2
3
4
5
REF  
Converting, VA = 5V, VREF = 2.5V: 8.6 mW  
(typ)  
CHA+  
CHA-  
CHB-  
CHB+  
SCLK  
ADC122S625  
8
D
OUT  
Power-Down, VA = 5V, VREF = 2.5V: 2.6 µW  
(typ)  
7
V
A
6
GND  
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
3
SPI, QSPI are trademarks of Motorola, Incorporated.  
All other 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 © 2008–2013, Texas Instruments Incorporated  
ADC122S625  
SNAS451A FEBRUARY 2008REVISED MARCH 2013  
www.ti.com  
Block Diagram  
SAR  
CHA+  
CHARGE  
REDISTRIBUTION  
DAC  
S/H  
CHA-  
COMPARATOR  
SERIAL  
INTERFACE  
SAR  
V
REF  
CHB-  
CHARGE  
REDISTRIBUTION  
DAC  
S/H  
CHB+  
COMPARATOR  
PIN DESCRIPTIONS AND EQUIVALENT CIRCUITS  
Pin No.  
Symbol  
Description  
Voltage Reference Input. A voltage reference between 1V and VA must be applied to this  
input. VREF must be decoupled to GND with a minimum ceramic capacitor value of 0.1 µF.  
A bulk capacitor value of 1.0 µF to 10 µF in parallel with the 0.1 µF is recommended for  
enhanced performance.  
1
VREF  
Non-Inverting Input for Channel A. CHA+ is the positive analog input for the differential  
signal applied to Channel A.  
2
3
4
CHA+  
CHA  
CHB−  
Inverting Input for Channel A. CHAis the negative analog input for the differential signal  
applied to Channel A.  
Inverting Input for Channel B. CHBis the negative analog input for the differential signal  
applied to Channel B.  
Non-Inverting Input for Channel B. CHB+ is the positive analog input for the differential  
signal applied to Channel B.  
5
6
CHB+  
GND  
Ground. GND is the ground reference point for all signals applied to the ADC122S625.  
Analog Power Supply input. A voltage source between 4.5V and 5.5V must be applied to  
this input. VA must be decoupled to GND with a minimum ceramic capacitor value of 0.1  
µF. A bulk capacitor value of 1.0 µF to 10 µF in parallel with the 0.1 µF is recommended for  
enhanced performance.  
7
8
VA  
Serial Data Output for Channel A and Channel B. The serial data output word is comprised  
of 4 null bits, 12 data bits (ChA conversion result), 4 null bits, and 12 data bits (ChB  
conversion result). During a conversion, the data is output on the falling edges of SCLK and  
is valid on the rising edges.  
DOUT  
9
SCLK  
CS  
Serial Clock. SCLK is used to control data transfer and serves as the conversion clock.  
Chip Select Bar. CS is active low. The ADC122S625 is actively converting when CS is  
LOW and Power-Down Mode when CS is HIGH. A conversion begins on the fall of CS.  
10  
2
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ADC122S625  
www.ti.com  
SNAS451A FEBRUARY 2008REVISED MARCH 2013  
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam  
during storage or handling to prevent electrostatic damage to the MOS gates.  
Absolute Maximum Ratings(1)(2)(3)  
Analog Supply Voltage VA  
0.3V to 6.5V  
0.3V to (VA +0.3V)  
±10 mA  
Voltage on Any Pin to GND  
(4)  
Input Current at Any Pin  
(4)  
Package Input Current  
±50 mA  
(5)  
Power Consumption at TA = 25°C  
See  
(6)  
ESD Susceptibility  
Human Body Model  
Machine Model  
2500V  
250V  
Charge Device Model  
1000V  
Junction Temperature  
Storage Temperature  
+150°C  
65°C to +150°C  
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for  
which the device is functional, but do not ensure specific performance limits. For ensured specifications and test conditions, see the  
Electrical Characteristics. The ensured specifications apply only for the test conditions listed. Some performance characteristics may  
degrade when the device is not operated under the listed test conditions. Operation of the device beyond the maximum Operating  
Ratings is not recommended.  
(2) All voltages are measured with respect to GND = 0V, unless otherwise specified.  
(3) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and  
specifications.  
(4) When the input voltage at any pin exceeds the power supplies (that is, VIN < GND or VIN > VA), the current at that pin should be limited  
to 10 mA. The 50 mA maximum package input current rating limits the number of pins that can safely exceed the power supplies with an  
input current of 10 mA to five.  
(5) The absolute maximum junction temperature (TJmax) for this device is 150°C. The maximum allowable power dissipation is dictated by  
TJmax, the junction-to-ambient thermal resistance (θJA), and the ambient temperature (TA), and can be calculated using the formula  
PDMAX = (TJmax TA)/θJA. The values for maximum power dissipation listed above will be reached only when the ADC122S625 is  
operated in a severe fault condition (e.g. when input or output pins are driven beyond the power supply voltages, or the power supply  
polarity is reversed). Such conditions should always be avoided.  
(6) Human body model is a 100 pF capacitor discharged through a 1.5 kresistor. Machine model is a 220 pF capacitor discharged  
through 0 . Charge device model simulates a pin slowly acquiring charge (such as from a device sliding down the feeder in an  
automated assembler) then rapidly being discharged.  
Operating Ratings(1)(2)  
Operating Temperature Range  
40°C TA +105°C  
+4.5V to +5.5V  
1.0V to VA  
Supply Voltage, VA  
Reference Voltage, VREF  
Input Common-Mode Voltage, VCM  
Digital Input Pins Voltage Range  
Clock Frequency  
See Figure 36  
0 to VA  
1.6 MHz to 6.4 MHz  
VREF to +VREF  
Differential Analog Input Voltage  
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for  
which the device is functional, but do not ensure specific performance limits. For ensured specifications and test conditions, see the  
Electrical Characteristics. The ensured specifications apply only for the test conditions listed. Some performance characteristics may  
degrade when the device is not operated under the listed test conditions. Operation of the device beyond the maximum Operating  
Ratings is not recommended.  
(2) All voltages are measured with respect to GND = 0V, unless otherwise specified.  
Package Thermal Resistance  
Package  
θJA  
10-lead VSSOP  
240°C / W  
Soldering process must comply with TI's Reflow Temperature Profile  
(1)  
specifications. Refer to http://www.ti.com/packaging  
(1) Reflow temperature profiles are different for lead-free packages.  
Copyright © 2008–2013, Texas Instruments Incorporated  
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ADC122S625  
SNAS451A FEBRUARY 2008REVISED MARCH 2013  
www.ti.com  
(1)  
ADC122S625 Converter Electrical Characteristics  
The following specifications apply for VA = +4.5V to 5.5V, VREF = 2.5V, fSCLK = 1.6 to 6.4 MHz, fIN = 20 kHz, CL = 25 pF,  
unless otherwise noted. Boldface limits apply for TA = TMIN to TMAX; all other limits are at TA = 25°C.  
Symbol  
Parameter  
Conditions  
Typical  
Limits  
Units  
STATIC CONVERTER CHARACTERISTICS  
Resolution with No Missing Codes  
12  
±1  
Bits  
LSB (max)  
LSB  
Integral Non-Linearity  
INL  
±0.5  
0.02  
±0.4  
0.02  
0.2  
0.1  
2  
Integral Non-Linearity Matching  
Differential Non-Linearity  
DNL  
±0.95  
±3  
LSB (max)  
LSB  
Differential Non-Linearity Matching  
Offset Error  
OE  
LSB (max)  
LSB  
Offset Error Matching  
Positive Gain Error  
±5  
LSB (max)  
LSB  
Positive Gain Error Matching  
0.2  
3
GE  
Negative Gain Error  
±8  
LSB (max)  
LSB  
Negative Gain Error Matching  
0.2  
DYNAMIC CONVERTER CHARACTERISTICS  
SINAD  
SNR  
Signal-to-Noise Plus Distortion Ratio fIN = 20 kHz, 0.1 dBFS  
72.5  
73.2  
83  
84  
69.5  
71  
dBc (min)  
dBc (min)  
dBc (max)  
dBc (min)  
bits (min)  
MHz  
Signal-to-Noise Ratio  
fIN = 20 kHz, 0.1 dBFS  
THD  
Total Harmonic Distortion  
Spurious-Free Dynamic Range  
Effective Number of Bits  
fIN = 20 kHz, 0.1 dBFS  
fIN = 20 kHz, 0.1 dBFS  
fIN = 20 kHz, 0.1 dBFS  
72  
72  
SFDR  
ENOB  
11.8  
26  
11.25  
Differential Input  
Output at 70.7%FS with  
FS Input  
FPBW  
ISOL  
3 dB Full Power Bandwidth  
Single-Ended Input  
22  
MHz  
Channel-to-Channel Isolation  
fIN < 1 MHz  
90  
dBc  
ANALOG INPUT CHARACTERISTICS  
VREF  
+VREF  
±1  
V (min)  
V (max)  
µA (max)  
pF  
VIN  
Differential Input Range  
DC Leakage Current  
Input Capacitance  
IDCL  
CINA  
VIN = VREF or VIN = -VREF  
In Track Mode  
20  
3
In Hold Mode  
pF  
See the Specification Definitions for the test  
condition  
CMRR  
VREF  
Common Mode Rejection Ratio  
Reference Voltage Range  
90  
dB  
1.0  
VA  
V (min)  
V (max)  
DIGITAL INPUT CHARACTERISTICS  
VIH  
VIL  
Input High Voltage  
Input Low Voltage  
Input Current  
2.4  
0.8  
±1  
4
V (min)  
V (max)  
µA (max)  
pF (max)  
IIN  
VIN = 0V or VA  
CIND  
Input Capacitance  
2
DIGITAL OUTPUT CHARACTERISTICS  
ISOURCE = 200 µA  
ISOURCE = 1 mA  
ISINK = 200 µA  
ISINK = 1 mA  
V
A 0.02  
A 0.09  
0.01  
V
A 0.2  
V (min)  
V
VOH  
Output High Voltage  
Output Low Voltage  
V
0.4  
V (max)  
V
VOL  
0.08  
IOZH, IOZL TRI-STATE Leakage Current  
Force 0V or VA  
Force 0V or VA  
±1  
4
µA (max)  
pF (max)  
COUT  
TRI-STATE Output Capacitance  
Output Coding  
2
Binary 2'S Complement  
(1) Tested limits are specified to TI's AOQL (Average Outgoing Quality Level).  
4
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ADC122S625  
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SNAS451A FEBRUARY 2008REVISED MARCH 2013  
ADC122S625 Converter Electrical Characteristics (1) (continued)  
The following specifications apply for VA = +4.5V to 5.5V, VREF = 2.5V, fSCLK = 1.6 to 6.4 MHz, fIN = 20 kHz, CL = 25 pF,  
unless otherwise noted. Boldface limits apply for TA = TMIN to TMAX; all other limits are at TA = 25°C.  
Symbol  
Parameter  
Conditions  
Typical  
Limits  
Units  
POWER SUPPLY CHARACTERISTICS  
4.5  
5.5  
V (min)  
V (max)  
VA  
Analog Supply Voltage  
IVA  
(Conv)  
Analog Supply Current,  
Continuously Converting  
fSCLK = 6.4 MHz, fS = 200 kSPS, fIN = 20 kHz,  
VA = 5V  
1.7  
20  
2.45  
40  
mA (max)  
µA (max)  
IVREF  
(Conv)  
Reference Current, Continuously  
Converting  
fSCLK = 6.4 MHz, fS = 200 kSPS, VREF = 2.5V  
fSCLK = 6.4 MHz, VA = 5.0V  
10  
µA  
Analog Supply Current, Power Down  
Mode (CS high)  
IVA (PD)  
(2)  
fSCLK = 0, VA = 5.0V  
0.5  
1.1  
µA (max)  
µA  
fSCLK = 6.4 MHz, VREF = 2.5V  
0.05  
0.05  
IVREF  
(PD)  
Reference Current, Power Down  
Mode (CS high)  
(2)  
fSCLK = 0, VREF = 2.5V  
0.1  
µA (max)  
PWR  
(Conv)  
Power Consumption, Continuously  
Converting  
fSCLK = 6.4 MHz, fS = 200 kSPS, fIN = 20 kHz,  
VA = 5.0V, VREF = 2.5V  
8.6  
12.4  
mW (max)  
fSCLK = 6.4 MHz, VA = 5.0V, VREF = 2.5V  
fSCLK = 0, VA = 5.0V, VREF = 2.5V  
50  
µW  
PWR  
(PD)  
Power Consumption, Power Down  
Mode (CS high)  
2.6  
5.8  
µW (max)  
See the Specification Definitions for the test  
condition  
PSRR  
Power Supply Rejection Ratio  
85  
dB  
AC ELECTRICAL CHARACTERISTICS  
fSCLK  
fSCLK  
Maximum Clock Frequency  
Minimum Clock Frequency  
Maximum Sample Rate(3)  
Minimum Sample Rate  
Track/Hold Acquisition Time  
Conversion Time  
20  
0.8  
625  
25  
6.4  
1.6  
200  
50  
MHz (min)  
MHz (max)  
kSPS (min)  
kSPS (min)  
SCLK cycles  
SCLK cycles  
ns  
fS  
tACQ  
tCONV  
tAD  
3
12  
Aperture Delay  
6
(2) Specified by design, characterization, or statistical analysis and is not tested at final test.  
(3) While the maximum sample rate is fSCLK/32, the actual sample rate may be lower than this by having the CS rate slower than fSCLK/32.  
(1)  
ADC122S625 Timing Specifications  
The following specifications apply for VA = +4.5V to 5.5V, VREF = 2.5V, fSCLK = 1.6 MHz to 6.4 MHz, CL = 25 pF, unless  
otherwise noted. Boldface limits apply for TA = TMIN to TMAX: all other limits TA = 25°C.  
Symbol  
Parameter  
Conditions  
Typical  
Limits  
Units  
ns (min)  
ns (max)  
ns (max)  
ns (min)  
ns (max)  
ns (max)  
ns (min)  
ns (min)  
ns  
4
7
tCSSU  
CS Setup Time prior to an SCLK rising edge  
1/ fSCLK  
1/ fSCLK - 3  
tEN  
tDH  
tDA  
tDIS  
tCH  
tCL  
tr  
DOUT Enable Time after the falling edge of CS  
DOUT Hold time after an SCLK Falling edge  
DOUT Access time after an SCLK Falling edge  
DOUT Disable Time after the rising edge of CS(2)  
SCLK High Time  
9
9
20  
6
20  
10  
26  
20  
25  
25  
SCLK Low Time  
DOUT Rise Time  
7
7
tf  
DOUT Fall Time  
ns  
(1) Tested limits are specified to TI's AOQL (Average Outgoing Quality Level).  
(2) tDIS is the time for DOUT to change 10%.  
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Timing Diagrams  
t
t
ACQ  
CONV  
10  
CS  
1
2
3
4
5
6
7
8
9
11  
12  
13  
14  
15  
16  
SCLK  
DOUT  
4 Leading Zeroes  
DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0  
Channel A Data  
t
Power Down  
CS  
17  
18  
19  
20  
21  
22  
23  
24  
25  
26  
27  
28  
29  
30  
31  
32  
SCLK  
DOUT  
4 Leading Zeroes  
DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0  
Channel B Data  
Figure 1. ADC122S625 Single Conversion Timing Diagram  
t
t
t
PD  
t
t
CONV  
ACQ  
CONV  
ACQ  
CS  
1
2
3
4
5
6
15  
16  
17  
18  
19  
20  
21  
22  
31  
32  
33  
34  
35  
36  
37  
38  
47  
48  
SCLK  
D
DB11 DB10  
MSB  
DB1 DB0  
LSB  
DB11 DB10  
MSB  
DB1 DB0  
LSB  
DB11 DB10  
MSB  
DB1 DB0  
LSB  
OUT  
HI-Z  
Channel A Data  
Channel B Data  
Channel A Data  
Figure 2. ADC122S625 Continuous Conversion Timing Diagram  
2.4V  
D
OUT  
0.8V  
t
f
t
r
Figure 3. DOUT Rise and Fall Times  
SCLK  
V
IL  
t
DA  
2.4V  
0.8V  
D
OUT  
t
DH  
Figure 4. DOUT Hold and Access Times  
6
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SCLK  
CS  
1
2
t
CSSU  
Figure 5. Valid CS Assertion Times  
V
IH  
CS  
90%  
90%  
D
D
OUT  
10%  
t
DIS  
90%  
OUT  
10%  
10%  
Figure 6. Voltage Waveform for tDIS  
Specification Definitions  
APERTURE DELAY is the time between the fourth falling edge of SCLK and the time when the input signal is  
acquired or held for conversion.  
COMMON MODE REJECTION RATIO (CMRR) is a measure of how well in-phase signals common to both input  
pins are rejected.  
To calculate CMRR, the change in output offset is measured while the common mode input voltage is changed  
from 2V to 3V.  
CMRR = 20 LOG ( Δ Output Offset / Δ Common Input)  
(1)  
CONVERSION TIME is the time required, after the input voltage is acquired, for the ADC to convert the input  
voltage to a digital word.  
DIFFERENTIAL NON-LINEARITY (DNL) is the measure of the maximum deviation from the ideal step size of 1  
LSB.  
DUTY CYCLE is the ratio of the time that a repetitive digital waveform is high to the total time of one period. The  
specification here refers to the SCLK.  
EFFECTIVE NUMBER OF BITS (ENOB, or EFFECTIVE BITS) is another method of specifying Signal-to-Noise  
and Distortion or SINAD. ENOB is defined as (SINAD 1.76) / 6.02 and says that the converter is equivalent to  
a perfect ADC of this (ENOB) number of bits.  
FULL POWER BANDWIDTH is a measure of the frequency at which the reconstructed output fundamental  
drops 3 dB below its low frequency value for a full scale input.  
INTEGRAL NON-LINEARITY (INL) is a measure of the deviation of each individual code from a line drawn from  
negative full scale (½ LSB below the first code transition) through positive full scale (½ LSB above the last code  
transition). The deviation of any given code from this straight line is measured from the center of that code value.  
MISSING CODES are those output codes that will never appear at the ADC outputs. The ADC122S625 is  
specified not to have any missing codes.  
NEGATIVE FULL-SCALE ERROR is the difference between the differential input voltage at which the output  
code transitions from negative full scale to the next code and VREF + 0.5 LSB.  
NEGATIVE GAIN ERROR is the difference between the negative full-scale error and the offset error.  
OFFSET ERROR is the difference between the differential input voltage at which the output code transitions from  
code 000h to 001h and 1/2 LSB.  
POSITIVE FULL-SCALE ERROR is the difference between the differential input voltage at which the output  
code transitions to positive full scale and VREF minus 1.5 LSB.  
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POSITIVE GAIN ERROR is the difference between the positive full-scale error and the offset error.  
POWER SUPPLY REJECTION RATIO (PSRR) is a measure of how well a change in supply voltage is rejected.  
PSRR is calculated from the ratio of the change in offset error for a given change in supply voltage, expressed in  
dB. For the ADC122S625, VA is changed from 4.5V to 5.5V.  
PSRR = 20 LOG (ΔOffset / ΔVA)  
(2)  
SIGNAL TO NOISE RATIO (SNR) is the ratio, expressed in dB, of the rms value of the input signal to the rms  
value of the sum of all other spectral components below one-half the sampling frequency, not including  
harmonics or d.c.  
SIGNAL TO NOISE PLUS DISTORTION (S/N+D or SINAD) Is the ratio, expressed in dB, of the rms value of the  
input signal to the rms value of all of the other spectral components below half the clock frequency, including  
harmonics but excluding d.c.  
SPURIOUS FREE DYNAMIC RANGE (SFDR) is the difference, expressed in dB, between the desired signal  
amplitude to the amplitude of the peak spurious spectral component, where a spurious spectral component is  
any signal present in the output spectrum that is not present at the input and may or may not be a harmonic.  
TOTAL HARMONIC DISTORTION (THD) is the ratio of the rms total of the first five harmonic components at the  
output to the rms level of the input signal frequency as seen at the output, expressed in dB. THD is calculated as  
2
Af22 +3+ Af6  
THD = 20 log10  
2
Af1  
(3)  
where Af1 is the RMS power of the input frequency at the output and Af2 through Af6 are the RMS power in the  
first 5 harmonic frequencies.  
THROUGHPUT TIME is the minimum time required between the start of two successive conversion.  
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Typical Performance Characteristics  
VA = 5.0V, VREF = 2.5V, TA = +25°C, fSAMPLE = 200 kSPS, fSCLK = 6.4 MHz, fIN = 20 kHz unless otherwise stated.  
DNL - 200 kSPS  
INL - 200 kSPS  
Figure 7.  
Figure 8.  
DNL vs. VA  
INL vs. VA  
Figure 9.  
Figure 10.  
DNL vs. VREF  
INL vs. VREF  
Figure 11.  
Figure 12.  
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Typical Performance Characteristics (continued)  
VA = 5.0V, VREF = 2.5V, TA = +25°C, fSAMPLE = 200 kSPS, fSCLK = 6.4 MHz, fIN = 20 kHz unless otherwise stated.  
DNL vs. SCLK FREQUENCY  
INL vs. SCLK FREQUENCY  
Figure 13.  
Figure 14.  
DNL vs. TEMPERATURE  
INL vs. TEMPERATURE  
Figure 15.  
Figure 16.  
SINAD vs. VA  
THD vs. VA  
Figure 17.  
Figure 18.  
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Typical Performance Characteristics (continued)  
VA = 5.0V, VREF = 2.5V, TA = +25°C, fSAMPLE = 200 kSPS, fSCLK = 6.4 MHz, fIN = 20 kHz unless otherwise stated.  
SINAD vs. VREF  
THD vs. VREF  
Figure 19.  
Figure 20.  
SINAD vs. SCLK FREQUENCY  
THD vs. SCLK FREQUENCY  
Figure 21.  
Figure 22.  
SINAD vs. INPUT FREQUENCY  
THD vs. INPUT FREQUENCY  
Figure 23.  
Figure 24.  
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Typical Performance Characteristics (continued)  
VA = 5.0V, VREF = 2.5V, TA = +25°C, fSAMPLE = 200 kSPS, fSCLK = 6.4 MHz, fIN = 20 kHz unless otherwise stated.  
SINAD vs. TEMPERATURE  
THD vs. TEMPERATURE  
Figure 25.  
Figure 26.  
VA CURRENT vs. VA  
VA CURRENT vs. SCLK FREQ  
Figure 27.  
Figure 28.  
VA CURRENT vs. TEMPERATURE  
VREF CURRENT vs. SCLK FREQ  
Figure 29.  
Figure 30.  
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Typical Performance Characteristics (continued)  
VA = 5.0V, VREF = 2.5V, TA = +25°C, fSAMPLE = 200 kSPS, fSCLK = 6.4 MHz, fIN = 20 kHz unless otherwise stated.  
VREF CURRENT vs. TEMP  
CMRR vs. CM RIPPLE FREQ  
Figure 31.  
Figure 32.  
SPECTRAL RESPONSE - 200 kSPS  
Figure 33.  
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FUNCTIONAL DESCRIPTION  
The ADC122S625 is a dual 12-bit, simultaneous sampling Analog-to-Digital (A/D) converter. The converter is  
based on a successive-approximation register (SAR) architecture where the differential nature of the analog  
inputs is maintained from the internal track-and-hold circuits throughout the A/D converter. The analog inputs on  
both channels are sampled simultaneously to preserve their relative phase information to each other. The  
architecture and process allow the ADC122S625 to acquire and convert dual analog signals at sample rates up  
to 200 kSPS while consuming very little power.  
The ADC122S625 requires an external reference, external clock, and an analog power supply. The analog  
supply (VA) can range from 4.5V to 5.5V and the external reference can be any voltage between 1V and VA. The  
value of the reference voltage determines the range of the analog input, while the reference input current  
depends upon the conversion rate.  
Analog inputs are presented at the inputs of Channel A and Channel B. Upon initiation of a conversion, the  
differential input at these pins is sampled on the internal capacitor array. The analog input signals are  
disconnected from the external circuitry while a conversion is in progress.  
The external clock can take on values as indicated in the Electrical Characteristics Table. The duty cycle of the  
clock is essentially unimportant, provided the minimum clock high and low times are met. The minimum clock  
frequency is set by internal capacitor leakage. Each conversion requires thirty-two clock cycles to complete.  
The ADC122S625 offers a high-speed serial data output that is binary 2's complement and compatible with  
several standards, such as SPI™, QSPI™, MICROWIRE™, and many common DSP serial interfaces. The digital  
conversion result of Channel A and Channel B is clocked out on the falling edges of the SCLK input and is  
provided serially at DOUT, most significant bit first. The result of Channel A is output before the result of Channel  
B, with four zeros in between the two results. The digital data provided on DOUT is that of the conversion currently  
in progress. With CS held low after the result of Channel B is output, the ADC122S625 will continuously convert  
the analog inputs until CS is de-asserted (brought high). Having a single, serial DOUT makes the ADC122S625 an  
excellent replacement for two independent ADCs that are part of a daisy chain configuration and allows a system  
designer to save valuable board space and power.  
REFERENCE INPUT  
The externally supplied reference voltage sets the analog input range. The ADC122S625 will operate with a  
reference voltage in the range of 1V to VA.  
Operation with a reference voltage below 1V is also possible with slightly diminished performance. As the  
reference voltage (VREF) is reduced, the range of acceptable analog input voltages is reduced. Assuming a  
proper common-mode input voltage, the differential peak-to-peak input range is limited to twice VREF. See Input  
Common Mode Voltage for more details. Reducing the value of VREF also reduces the size of the least significant  
bit (LSB). The size of one LSB is equal to twice the reference voltage divided by 4096. When the LSB size goes  
below the noise floor of the ADC122S625, the noise will span an increasing number of codes and overall  
performance will suffer. For example, dynamic signals will have their SNR degrade, while D.C. measurements  
will have their code uncertainty increase. Since the noise is Gaussian in nature, the effects of this noise can be  
reduced by averaging the results of a number of consecutive conversions.  
Additionally, since offset and gain errors are specified in LSB, any offset and/or gain errors inherent in the A/D  
converter will increase in terms of LSB size as the reference voltage is reduced.  
The reference input and the analog inputs are connected to the capacitor array through a switch matrix when the  
input is sampled. Hence, the current requirements at the reference and at the analog inputs are a series of  
transient spikes that occur at a frequency dependent on the operating sample rate of the ADC122S625.  
The reference current changes only slightly with temperature. See the curves, Reference Current vs. SCLK  
Frequency and Reference Current vs. Temperature in the Typical Performance Characteristics section for  
additional details.  
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ANALOG SIGNAL INPUTS  
The ADC122S625 has dual differential inputs where the effective input voltage that is digitized is CHA+ minus  
CHA(DIFFINA) and CHB+ minus CHB(DIFFINB). As is the case with all differential input A/D converters,  
operation with a fully differential input signal or voltage will provide better performance than with a single-ended  
input. However, the ADC122S625 can be presented with a single-ended input as shown in Single-Ended Input  
Operation and the Application Circuits.  
The current required to recharge the input sampling capacitor will cause voltage spikes at the + and inputs. Do  
not try to filter out these noise spikes. Rather, ensure that the noise spikes settle out during the acquisition period  
(three SCLK cycles after the fall of CS). This is true for both Channel A and Channel B since both channels are  
converted simultaneously on the fourth falling edge of SCLK after CS is asserted.  
Differential Input Operation  
With a fully differential input voltage or signal, a positive full scale output code (0111 1111 1111b or 7FFh) will be  
obtained when DIFFINA or DIFFINB is greater than or equal to VREF 1.5 LSB. A negative full scale code (1000  
0000 0000b or 800h) will be obtained when DIFFINA or DIFFINB is greater than or equal to VREF + 0.5 LSB.  
This ignores gain, offset and linearity errors, which will affect the exact differential input voltage that will  
determine any given output code. Figure 34 shows the ADC122S625 being driven by a full-scale differential  
source.  
VREF  
2
VCM  
VREF  
2
VCM  
+
-
VCM  
RS  
+
SRC  
CS  
ADC122S625  
-
RS  
VREF  
2
VCM  
VREF  
VCM  
+
-
VCM  
2
Figure 34. Differential Input  
Single-Ended Input Operation  
For single-ended operation, the non-inverting inputs of the ADC122S625 can be driven with a signal that has a  
maximum to minimum value range that is equal to or less than twice the reference voltage. The inverting inputs  
should be biased at a stable voltage that is halfway between these maximum and minimum values. In order to  
utilize the entire dynamic range of the ADC122S625, the reference voltage is limited at VA / 2. This allows the  
non-inverting inputs the maximum swing range of ground to VA. Figure 35 shows the ADC122S625 being driven  
by a full-scale single-ended source. Even though the design of the ADC122S625 is optimized for a differential  
input, there is very little performance degradation while operating the ADC122S625 in single-ended fashion.  
VCM + VREF  
VCM  
VCM - VREF  
RS  
+
CS  
ADC122S625  
-
SRC  
VCM  
Figure 35. Single-Ended Input  
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Input Common Mode Voltage  
The allowable input common mode voltage (VCM) range depends upon the supply and reference voltages used  
for the ADC122S625. The ranges of VCM for differential and single-ended operation are depicted in Figure 36 and  
Figure 37. Equations for calculating the minimum and maximum common mode voltages for differential and  
single-ended operation are shown in Table 1.  
6
Differential Input  
5
V
= 5.0V  
A
3.75  
2.5  
1.25  
0
-1  
0.0  
1.0  
2.0 2.5 3.0  
(V)  
4.0  
5.0  
V
REF  
Figure 36. VCM range for Differential Input operation  
6
Single-Ended Input  
5
V
= 5.0V  
A
3.75  
2.5  
1.25  
0
-1  
0.0  
0.75  
1.25  
(V)  
1.75  
2.5  
V
REF  
Figure 37. VCM range for single-ended operation  
Table 1. Allowable VCM Range  
Input Signal  
Minimum VCM  
VREF / 2  
Maximum VCM  
A VREF / 2  
A VREF  
Differential  
V
Single-Ended  
VREF  
V
SERIAL DIGITAL INTERFACE  
The ADC122S625 communicates via a synchronous serial interface as shown in the Timing Diagrams section.  
CS, chip select, initiates conversions and frames the serial data transfers. SCLK (serial clock) controls both the  
conversion process and the timing of the serial data. DOUT is the serial data output pin, where the conversion  
results of Channel A and Channel B are sent as a serial data stream, with the result of Channel A output before  
the result of Channel B.  
A serial frame is initiated on the falling edge of CS and ends on the rising edge of CS. The ADC122S625's DOUT  
is in a high impedance state when CS is high (asserted) and is active when CS is low (de-asserted); thus CS  
acts as an output enable. A timing diagram for a single conversion is shown in Figure 1.  
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During the first three cycles of SCLK, the ADC122S625 is in acquisition mode (tACQ), tracking the input voltage  
on both Channel A and Channel B. For the next twelve SCLK cycles (tCONV), the conversion of Channel A and  
Channel B is accomplished simultaneously and data is presented on DOUT, one bit at a time. SCLK falling edges  
one through four clock out leading zeros while falling edges five through sixteen clock out the conversion result  
of Channel A, MSB first. The process is repeated in order to clock out the result of Channel B, with SCLK falling  
edges seventeen through twenty clocking out four zeros followed by falling edges twenty-one through thirty-two  
clokcing out the conversion result of Channel B. If there is more than one conversion in a frame (continuous  
conversion mode), the ADC122S625 will re-enter acquisition mode on the falling edge of SCLK after the N*32  
rising edge of SCLK and re-enter conversion mode on the N*32+4 falling edge of SCLK as shown in Figure 2.  
"N" is an integer value.  
The ADC122S625 can enter acquisition mode under three different conditions. The first condition involves CS  
going low (asserted) with SCLK high. In this case, the ADC122S625 enters acquisition mode on the first falling  
edge of SCLK after CS is asserted. In the second condition, CS goes low with SCLK low. Under this condition,  
the ADC122S625 automatically enters acquisition mode and the falling edge of CS is seen as the first falling  
edge of SCLK. In the third condition, CS and SCLK go low simultaneously and the ADC122S625 immediately  
enters acquisition mode. While there is no timing restriction with respect to the falling edges of CS and the falling  
edge of SCLK, see Figure 5 for setup and hold time requirements for the falling edge of CS with respect to the  
rising edge of SCLK.  
CS Input  
The CS (chip select bar) is an active low input that is TTL and CMOS compatible. The ADC122S625 transitions  
from acquisition mode, to conversion mode, to power-down mode when CS is low and is always in power-down  
mode when CS is high. The falling edge of CS marks the beginning of a conversion where the input to Channel  
A and Channel B are tracked by the input sampling capacitor. The rising edge of CS marks the end of a  
conversion window. As a result, CS frames the conversion window and can be used to control the sample rate of  
the ADC122S625. While the SCLK frequency is limited to a range of 1.6 MHz to 6.4 MHz, the frequency of CS  
has no limitation. This allows a system designer to operate the ADC122S625 at sample rates approaching zero  
samples per second if conserving power is very important. See Burst Mode Operation for more details. Multiple  
conversions can occur within a given conversion frame with each conversion requiring thirty-two SCLK cycles.  
This is referred to as continuous conversion mode and is shown in Figure 2 of the Timing Diagrams section.  
Proper operation requires that the fall of CS not occur simultaneously with a rising edge of SCLK. If the fall of CS  
occurs during the rising edge of SCLK, the data might be clocked out one bit early. Whether or not the data is  
clocked out early depends upon how close the CS transition is to the SCLK transition, the device temperature,  
and characteristics of the individual device. To ensure that the MSB is always clocked out at a given time (the  
5th falling edge of SCLK), it is essential that the fall of CS always meet the timing requirement specified in the  
Timing Specification table.  
SCLK Input  
The SCLK (serial clock) serves two purposes in the ADC122S625. It is used by the ADC122S625 as the  
conversion clock and it is used as the serial clock to output the conversion results. The SCLK input is TTL and  
CMOS compatible. Internal settling time requirements limit the maximum clock frequency while internal capacitor  
leakage limits the minimum clock frequency. The ADC122S625 offers specified performance with the clock rates  
indicated in the Electrical Characteristics Table.  
Data Output(s)  
The conversion result of Channel A and Channel B is output on DOUT, with the result of Channel A being output  
before the result of Channel B. The data output format of the ADC122S625 is binary, two’s complement, as  
shown in Table 2. This table indicates the ideal output code for a given input voltage and does not include the  
effects of offset, gain error, linearity errors, or noise. Each data output bit is output on the falling edges of SCLK.  
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Table 2. Ideal Output Code vs. Input Voltage  
Analog Input  
(+IN) (IN)  
2's Complement Binary Output  
2's Comp. Hex Code  
2's Comp. Dec Code  
VREF 1.5 LSB  
+ 0.5 LSB  
0111 1111 1111  
0000 0000 0001  
0000 0000 0000  
1111 1111 1111  
1000 0000 0000  
7FF  
001  
000  
FFF  
800  
2047  
1
0.5 LSB  
0
0V 1.5 LSB  
VREF + 0.5 LSB  
1  
2048  
While data is output on the falling edges of SCLK, receiving systems have the option of capturing the data from  
the ADC122S625 on the subsequent rising or falling edge of SCLK. If a receiving system is going to capture data  
on the subsequent falling edges of SCLK, it is important to make sure that the minimum hold time after an SCLK  
falling edge (tDH) is acceptable. See Figure 4 for DOUT hold and access times.  
DOUT is enabled on the falling edge of CS and disabled on the rising edge of CS. If CS is raised prior to the 16th  
falling edge of SCLK, the current conversion is aborted and DOUT will go into its high impedance state. A new  
conversion will begin when CS is taken LOW.  
Applications Information  
OPERATING CONDITIONS  
We recommend that the following conditions be observed for operation of the ADC122S625:  
40°C TA +105°C  
+4.5V VA +5.5V  
1V VREF VA  
1.6 MHz fSCLK 6.4 MHz  
VCM: See Input Common Mode Voltage  
POWER CONSUMPTION  
The architecture, design, and fabrication process allow the ADC122S625 to operate at conversion rates up to  
200 kSPS while consuming very little power. The ADC122S625 consumes the least amount of power while  
operating in power down mode. For applications where power consumption is critical, the ADC122S625 should  
be operated in power down mode as often as the application will tolerate. To further reduce power consumption,  
stop the SCLK while CS is high.  
Burst Mode Operation  
Normal operation of the ADC122S625 requires the SCLK frequency to be thirty-two times the sample rate and  
the CS rate to be the same as the sample rate. However, in order to minimize power consumption in applications  
requiring sample rates below 50 kSPS, the ADC122S625 should be run with an SCLK frequency of 6.4 MHz and  
a CS rate as slow as the system requires. When this is accomplished, the ADC122S625 is operating in burst  
mode. The ADC122S625 enters into power down mode at the end of each conversion, minimizing power  
consumption. This causes the converter to spend the longest possible time in power down mode. Since power  
consumption scales directly with conversion rate, minimizing power consumption requires determining the lowest  
conversion rate that will satisfy the requirements of the system.  
POWER SUPPLY CONSIDERATIONS AND PCB LAYOUT  
For best performance, care should be taken with the physical layout of the printed circuit board. This is especially  
true with a low reference voltage or when the conversion rate is high. At high clock rates there is less time for  
settling, so it is important that any noise settles out before the conversion begins.  
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Analog Power Supply  
Any ADC architecture is sensitive to spikes on the power supply, reference, and ground pins. These spikes may  
originate from switching power supplies, digital logic, high power devices, and other sources. Power to the  
ADC122S625 should be clean and well bypassed. A 0.1 µF ceramic bypass capacitor and a 1 µF to 10 µF  
capacitor should be used to bypass the ADC122S625 supply, with the 0.1 µF capacitor placed as close to the  
ADC122S625 package as possible.  
Since the ADC122S625 has a separate analog and reference pin, the user has two options. The first option is to  
tie the analog and reference supply pins together and power them with the same power supply. This is the most  
cost effective way of powering the ADC122S625 but it is also the least ideal. As stated previously, noise from the  
analog supply pin can couple into the reference supply pin and adversely affect performance. The other option  
involves the user powering the analog and reference supply pins with separate supply voltages. These supply  
voltages can have the same amplitude or they can be different. The only design constraint is that the reference  
supply voltage be less than the analog supply voltage.  
Voltage Reference  
The reference source must have a low output impedance and needs to be bypassed with a minimum capacitor  
value of 0.1 µF. A larger capacitor value of 1 µF to 10 µF placed in parallel with the 0.1 µF is preferred. While the  
ADC122S625 draws very little current from the reference on average, there are higher instantaneous current  
spikes at the reference input.  
The reference input of the ADC122S625, like all A/D converters, does not reject noise or voltage variations. Keep  
this in mind if the reference voltage is derived from the power supply. Any noise and/or ripple from the supply  
that is not rejected by the external reference circuitry will appear in the digital results. The use of an active  
reference source is recommended. The LM4040 and LM4050 shunt reference families and the LM4132 and  
LM4140 series reference families are excellent choices for a reference source.  
PCB Layout  
Capacitive coupling between the noisy digital circuitry and the sensitive analog circuitry can lead to poor  
performance. The solution is to keep the analog circuitry separated from the digital circuitry and the clock line as  
short as possible. Digital circuits create substantial supply and ground current transients. The logic noise  
generated could have significant impact upon system noise performance. To avoid performance degradation of  
the ADC122S625 due to supply noise, avoid sharing the power supplies for VA and VREF with other digital  
circuitry on the board.  
Generally, analog and digital lines should cross each other at 90° to avoid crosstalk. However, to maximize  
accuracy in high resolution systems, avoid crossing analog and digital lines altogether. It is important to keep  
clock lines as short as possible and isolated from other lines, including other digital lines. In addition, the clock  
line should also be treated as a transmission line and be properly terminated. The analog input should be  
isolated from noisy signal traces to avoid coupling of spurious signals into the input. Any external component  
(e.g., a filter capacitor) connected between the converter's input pins and ground or to the reference input pin  
and ground should be connected to a very clean point in the ground plane.  
A single, uniform ground plane and the use of split power planes are recommended. The power planes should be  
located within the same board layer. All analog circuitry (input amplifiers, filters, reference components, etc.)  
should be placed over the analog power plane. All digital circuitry and I/O lines should be placed over the digital  
power plane. Furthermore, the GND pin on the ADC122S625 and all the components in the reference circuitry  
and input signal chain that are connected to ground should be connected to the ground plane at a quiet point.  
Avoid connecting these points too close to the ground point of a microprocessor, microcontroller, digital signal  
processor, or other high power digital device.  
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APPLICATION CIRCUITS  
The following figures are examples of the ADC122S625 in typical application circuits. These circuits are basic  
and will generally require modification for specific circumstances.  
Data Acquisition  
Figure 38 shows a basic low cost, low power data acquisition circuit. The analog supply pin is powered by the  
system +5V supply and the 2.5V reference voltage is generated by the LM4040-2.5 shunt reference.  
+5V  
+
10 mF  
2 kW  
ADC122S625  
V
REF  
V
A
+
0.1 mF  
0.1 mF  
10 mF  
LM4040-2.5  
Microcontroller  
CHA+ SCLK  
DIFFINA  
DIFFINB  
CHA-  
GND  
D
OUT  
CSB  
CHB-  
CHB+  
Figure 38. Low cost, low power Data Acquisition System  
Current Sensing Application  
Figure 39 shows an example of interfacing a pair of current transducers to the ADC122S625. The current  
transducers convert an input current into a voltage that is converted by the ADC122S625. Since the output  
voltage of the current transducers are single-ended and centered around a common-mode voltage of 2.5V, the  
ADC122S625 is configured with the output of the transducer driving the non-inverting inputs and the common-  
mode output voltage of the transducer driving the inverting input. The output of the transducer has an output  
range of ±2V around the common-mode voltage of 2.5V. As a result, a series reference voltage of 2.0V is  
connected to the ADC122S625. This will allow all of the codes of the ADC122S625 to be available for the  
application. This configuration of the ADC122S625 is referred to as a single-ended application of a differential  
ADC. All of the elements in the application are conveniently powered by the same +5V power supply, keeping  
circuit complexity and cost to a minimum.  
+5V  
+
10 mF  
LM4132-2.0  
V
REF  
V
A
ADC122S625  
+
0.1 mF  
0.1 mF  
10 mF  
2.5V + 2.0V  
2.5V  
CHA+  
OUT  
+5V  
I
IN  
I
I
IN  
ADC  
ADC  
SCLK  
V
OUT  
CM  
CHA-  
GND  
GND  
I
I
OUT  
D
OUT  
Serial  
Interface  
CSB  
CHB-  
2.5V  
V
CM  
I
IN  
I
IN  
+5V  
OUT  
GND  
2.5V + 2.0V  
I
OUT  
CHB+  
OUT  
LTSR-15NPs  
Figure 39. Interfacing the ADC122S625 to a Current Transducer  
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Bridge Sensor Application  
Figure 40 shows an example of interfacing the ADC122S625 to a pair of bridge sensors. The application  
assumes that the bridge sensors require buffering and amplification to fully utilize the dynamic range of the ADC  
and thus optimize the performance of the entire signal path. The amplification stage for each ADC input consists  
of a pair of opamps from the LMP7704. The amplification stage offers the benefit of high input impedance and  
potentially high amplification. On the other hand, it offers no common-mode rejection of noise coming from the  
bridge sensors. The application circuit assumes the bridge sensors are powered from the same +5V power  
supply voltage as the analog supply pin on the ADC122S625. This has the benefit of providing the ideal  
common-mode input voltage for the ADC122S625 while keeping design complexity and cost to a minimum. The  
LM4132-4.1, a 4.1V series reference, is used as the reference voltage in the application.  
+5V  
+5V = V  
A
+
-
470 pF  
180W  
ADC122S625  
ADC_A  
100 kW  
100 kW  
2 kW  
180W  
-
+
A
= 100 V/V  
V
Bridge  
Sensor  
SCLK  
DOUT  
LMP7704  
Serial Interface  
+5V  
CSB  
+
-
470 pF  
180W  
100 kW  
ADC_B  
2 kW  
180W  
100 kW  
V
REF  
-
+
A
V
= 100 V/V  
Bridge  
Sensor  
LM4132-4.1  
4.7 mF  
+5V  
+
+
0.1 mF  
4.7 mF  
Figure 40. Interfacing the ADC122S625 to Bridge Sensors  
Copyright © 2008–2013, Texas Instruments Incorporated  
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21  
Product Folder Links: ADC122S625  
 
 
ADC122S625  
SNAS451A FEBRUARY 2008REVISED MARCH 2013  
www.ti.com  
REVISION HISTORY  
Changes from Original (March 2013) to Revision A  
Page  
Changed layout of National Data Sheet to TI format .......................................................................................................... 21  
22  
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Copyright © 2008–2013, Texas Instruments Incorporated  
Product Folder Links: ADC122S625  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
(6)  
ADC122S625CIMM/NOPB  
ADC122S625CIMMX/NOPB  
ACTIVE  
ACTIVE  
VSSOP  
VSSOP  
DGS  
DGS  
10  
10  
1000 RoHS & Green  
3500 RoHS & Green  
SN  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
-40 to 105  
-40 to 105  
X35C  
X35C  
SN  
(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) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance  
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may  
reference these types of products as "Pb-Free".  
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.  
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based  
flame retardants must also meet the <=1000ppm threshold requirement.  
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.  
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation  
of the previous line and the two combined represent the entire Device Marking for that device.  
(6)  
Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two  
lines if the finish value exceeds the maximum column width.  
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  
10-Dec-2020  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
9-Aug-2022  
TAPE AND REEL INFORMATION  
REEL DIMENSIONS  
TAPE DIMENSIONS  
K0  
P1  
W
B0  
Reel  
Diameter  
Cavity  
A0  
A0 Dimension designed to accommodate the component width  
B0 Dimension designed to accommodate the component length  
K0 Dimension designed to accommodate the component thickness  
Overall width of the carrier tape  
W
P1 Pitch between successive cavity centers  
Reel Width (W1)  
QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPE  
Sprocket Holes  
Q1 Q2  
Q3 Q4  
Q1 Q2  
Q3 Q4  
User Direction of Feed  
Pocket Quadrants  
*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)  
ADC122S625CIMM/NOPB VSSOP  
DGS  
DGS  
10  
10  
1000  
3500  
178.0  
330.0  
12.4  
12.4  
5.3  
5.3  
3.4  
3.4  
1.4  
1.4  
8.0  
8.0  
12.0  
12.0  
Q1  
Q1  
ADC122S625CIMMX/  
NOPB  
VSSOP  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
9-Aug-2022  
TAPE AND REEL BOX DIMENSIONS  
Width (mm)  
H
W
L
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
ADC122S625CIMM/NOPB  
VSSOP  
VSSOP  
DGS  
DGS  
10  
10  
1000  
3500  
210.0  
367.0  
185.0  
367.0  
35.0  
35.0  
ADC122S625CIMMX/  
NOPB  
Pack Materials-Page 2  
PACKAGE OUTLINE  
DGS0010A  
VSSOP - 1.1 mm max height  
S
C
A
L
E
3
.
2
0
0
SMALL OUTLINE PACKAGE  
C
SEATING PLANE  
0.1 C  
5.05  
4.75  
TYP  
PIN 1 ID  
AREA  
A
8X 0.5  
10  
1
3.1  
2.9  
NOTE 3  
2X  
2
5
6
0.27  
0.17  
10X  
3.1  
2.9  
1.1 MAX  
0.1  
C A  
B
B
NOTE 4  
0.23  
0.13  
TYP  
SEE DETAIL A  
0.25  
GAGE PLANE  
0.15  
0.05  
0.7  
0.4  
0 - 8  
DETAIL A  
TYPICAL  
4221984/A 05/2015  
NOTES:  
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing  
per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not  
exceed 0.15 mm per side.  
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm per side.  
5. Reference JEDEC registration MO-187, variation BA.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
DGS0010A  
VSSOP - 1.1 mm max height  
SMALL OUTLINE PACKAGE  
10X (1.45)  
(R0.05)  
TYP  
SYMM  
10X (0.3)  
1
5
10  
SYMM  
6
8X (0.5)  
(4.4)  
LAND PATTERN EXAMPLE  
SCALE:10X  
SOLDER MASK  
OPENING  
SOLDER MASK  
OPENING  
METAL UNDER  
SOLDER MASK  
METAL  
0.05 MAX  
ALL AROUND  
0.05 MIN  
ALL AROUND  
SOLDER MASK  
DEFINED  
NON SOLDER MASK  
DEFINED  
SOLDER MASK DETAILS  
NOT TO SCALE  
4221984/A 05/2015  
NOTES: (continued)  
6. Publication IPC-7351 may have alternate designs.  
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
DGS0010A  
VSSOP - 1.1 mm max height  
SMALL OUTLINE PACKAGE  
10X (1.45)  
SYMM  
(R0.05) TYP  
10X (0.3)  
8X (0.5)  
1
5
10  
SYMM  
6
(4.4)  
SOLDER PASTE EXAMPLE  
BASED ON 0.125 mm THICK STENCIL  
SCALE:10X  
4221984/A 05/2015  
NOTES: (continued)  
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
9. Board assembly site may have different recommendations for stencil design.  
www.ti.com  
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DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”  
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