Analog-to-digital converter (ADC)
Low-Power/Cost-Optimized Circuits
Driving a SAR ADC directly without a front-end buffer circuit (low-power,
low-sampling-speed DAQ) ..........................................................................5
Low-power sensor measurements: 3.3-V, 1-ksps, 12-bit, single-ended,
dual-supply circuit ....................................................................................10
Low-power sensor measurements: 3.3-V, 1-ksps, 12-bit, single-ended,
Level Translation Input Drive Circuits
Circuit for driving a high-voltage SAR with an instrumentation amplifier
....23
Circuit for driving high-voltage SAR ADC with a buffered instrumentation
amplifier .....................................................................................................29
Circuit for driving high-voltage SAR ADCs for high-voltage, true differential
signal acquisition ......................................................................................36
Circuit to increase input range on an integrated analog front end (AFE)
SAR ADC ...................................................................................................45
High common-mode differential input voltage to ±10-V ADC input circuit
...... 50
High-current battery monitor circuit: 0−10 A, 0−10 kHz, 18 bit ...............57
High-input impedance, true differential, analog front end (AFE) attenuator
circuit for SAR ADCs .................................................................................63
High-voltage battery monitor circuit: ±20 V, 0-10 kHz, 18-bit fully
differential .................................................................................................. 71
Single-ended to differential signal conversion using an op amp and FDA
for unipolar signals ................................................................................... 78
Single-ended-to-differential circuit using an op amp and fully-differential
amplifier (FDA) for bipolar signals..............................................................85
Single-ended to differential using a two op-amp circuit ..........................92
True differential, 4 × 2 MUX, analog front end, simultaneous-sampling
ADC circuit ...............................................................................................100
Low-Level Sensor Input Circuits
Circuit for driving a switched-capacitor SAR ADC with a buffered
instrumentation amplifier ......................................................................109
Circuit for driving a switched-capacitor SAR ADC with an
instrumentation amplifier ......................................................................117
Circuit for driving an ADC with an instrumentation amplifier in high gain
..124
Low-input bias-current front end SAR ADC circuit ..............................131
High-side current shunt monitor circuit to 3-V single-ended ADC .......136
Two-wire PT100 RTD measurement circuit with low-side reference ....142
Three-wire PT100 RTD measurement circuit with high-side reference
and two IDAC current sources .............................................................148
Three-wire PT100 RTD measurement circuit with low-side reference
and one IDAC current source ...............................................................155
Three-wire PT100 RTD measurement circuit with low-side reference
and two IDAC current sources .............................................................161
Four-wire PT100 RTD measurement circuit with low-side reference ...168
Two-channel, K-type thermocouple measurement circuit with internal
temperature sensor CJC ......................................................................174
Input Protection, Filtering and Isolation Circuits
±12-V voltage sensing circuit with an isolated amplier and pseudo-
differential input SAR ADC ...................................................................181
±12-V voltage sensing circuit with an isolated amplier and differential
input SAR ADC .....................................................................................188
Anti-aliasing lter circuit design for single-ended ADC input using xed
cutoff frequency ...................................................................................195
Circuit showing overstress protection on ADC with integrated analog
front end ............................................................................................... 204
Digitally-isolated ADS8689 circuit design ............................................ 213
Reducing effects of external RC lter circuit on gain and drift error for
integrated analog front ends (AFEs): ±10 V .......................................... 217
Commonly Used Auxiliary Circuits
Isolated power supply, low-noise circuit: 5 V, 100 mA ......................... 223
Powering a dual-supply op-amp circuit with one LDO......................... 228
Digital-to-analog converter (DAC)
Audio Outputs
Active-filtering circuit for audio DAC .................................................... 232
Auxiliary circuits for high-performance audio .......................................237
Current-to-voltage converter circuit for audio DACs ........................... 243
Auxiliary and Biasing Circuits
Circuit for offset adjustment of input signals using precision DAC for
measurement equipment ..................................................................... 248
DAC force and sense reference drive circuit ........................................ 252
Power-supply margining circuit for LDOs using a precision DAC ........ 256
Power-supply margining circuit for SMPS using a precision DAC ....... 261
Current Sources
Loop-powered 4- to 20-mA transmitter circuit .................................... 266
Programmable low-side current sink circuit ......................................... 270
Programmable, two-stage, high-side current source circuit .................275
Voltage Sources
Circuit for differential output from a single-ended precision DAC ....... 280
High-current voltage output circuit using a precision DAC .. ................ 286
Progammable voltage output with sense connections circuit ............ 290
Unipolar negative voltage source from unipolar DAC circuit ............... 295
Unipolar voltage output DAC to bipolar voltage output circuit ............ 299
Table of Contents
single-supply circuit
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