ADC12032CIWM/NOPB - 12-Bit+Sign SAR ADC, 2-Channel | Texas Instruments
MPN: ADC12032CIWM/NOPB ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.5 | $7.50 |
| 10 | $6.8 | $68.00 |
| 100 | $6.05 | $605.00 |
| 500 | $5.4 | $2,700.00 |
| 1,000 | $4.75 | $4,750.00 |
ADC12032CIWM/NOPB Overview
An SAR ADC (Successive Approximation Register Analog-to-Digital Converter) is a type of data converter that uses a binary-search algorithm against an internal DAC to digitize an analog input within N clock cycles, where N is the resolution in bits. SAR converters sit in the data-converter hierarchy as: ADC -> SAR ADC -> data converter -> signal chain IC -> semiconductor. They are valued for deterministic latency, single-shot accuracy, and low power consumption, which makes them preferred for multiplexed multi-channel data-acquisition systems rather than continuous high-speed streaming applications.
Key features of the ADC12032 include 12-bit resolution with extended-sign coding for ±VREF bipolar inputs, integrated 2-channel analog input multiplexer, on-chip sample-and-hold, self-calibration (offset and gain) registers invoked at power-up or on demand, MICROWIRE/serial-compatible interface for low-pin-count host connection, and a single +5 V supply. The differential non-linearity (DNL) is rated at ±1 LSB maximum, with ±1 LSB integral non-linearity (INL) after calibration.
The device uses a charge-redistribution SAR architecture with a binary-weighted capacitor DAC, which inherently provides the sample-and-hold function. The built-in self-calibration trims both zero-scale and full-scale errors against an internal reference node, allowing the part to achieve specified accuracy without external trimming components. The serial data format includes a sign bit, allowing bipolar input ranges without external op-amps.
Typical applications include portable and bench-top digital multimeters, weigh scales and load-cell digitizers, panel meters and process-control front ends, temperature/pressure sensor signal chains, and industrial multi-channel data acquisition boards. The internal MUX and self-calibration make it particularly suited for low-channel-count, high-accuracy instrumentation.
When designing with this device, place 0.1 µF and 10 µF decoupling capacitors close to the supply pins, provide a clean low-impedance VREF (the ADC12032 expects an external +2.5 V to +5 V reference), and allow the calibration cycle to complete (tCAL ~2800 clock cycles) before issuing the first conversion command to guarantee specified accuracy.
This page synthesizes TI datasheet parameters, distributor pricing, package cross-references, and practical design guidance not aggregated in any single source on the web.
Drop-in alternatives for ADC12032CIWM/NOPB — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ADC12032CIWM/NOPB (same form factor and footprint) — differing in Analog Supply Voltage, Data Interface, Input Type, Operating Temperature, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADC12032CIWM
✅ Drop-In📋 Reference alternative (not in catalog)
ADC12030CIWM/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
ADC12032CIWMX/NOPB
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ADC10062CIWM/NOPB
✅ Drop-In✓ In Stock
$5.85 / Unit
View Datasheet →ADC10158CIWMX/NOPB
✅ Drop-In✓ In Stock
$5.74 / Unit
View Datasheet →ADC12032CIWM/NOPB Maximum Ratings & Electrical Characteristics
| Number of Bits | 12 (plus sign) |
| Architecture | SAR (Successive Approximation Register) |
| Number of Inputs | 1 or 2 (multiplexed) |
| Input Type | Single-ended (with sign bit for bipolar) |
| Data Interface | MICROWIRE-compatible Serial |
| Differential Non-Linearity (DNL) | ±1 LSB (max) |
| Integral Non-Linearity (INL) | ±1 LSB (max, after calibration) |
| Analog Supply Voltage | +5 V (single supply) |
| Digital Supply Voltage | +5 V (single supply) |
| Operating Temperature | -40 C to +85 C (industrial) |
| Package / Case | 20-SOIC (0.295 inch / 7.50 mm width) |
| Mounting Type | Surface Mount |
| Pin Count | 20 |
| Self-Calibration | Yes (offset + gain, on power-up or on demand) |
| Lead-Free Finish (S/NOPB suffix) | Yes (Pb-free, RoHS-compliant) |
| RoHS Status | Compliant |
ADC12032CIWM/NOPB Pin Configuration
| Pin 1 | VIN+ — Analog input, channel 1 (positive) |
| Pin 2 | VIN-/COM — Analog input, channel 2 / analog common |
| Pin 3 | REFIN+ — Positive reference input |
| Pin 4 | REFIN- — Negative reference input (ground) |
| Pin 5 | AGND — Analog ground |
| Pin 6 | DOUT — Serial data output (MICROWIRE) |
| Pin 7 | SCLK — Serial clock input |
| Pin 8 | /CS — Chip select (active low) |
| Pin 9 | SIGN — Sign bit output |
| Pin 10 | CAL — Calibration control (initiate self-cal) |
| Pin 11 | OSC1 — Oscillator pin 1 (or external clock in) |
| Pin 12 | OSC2 — Oscillator pin 2 (leave open if external clock used) |
| Pin 13 | DVDD — Digital +5 V supply |
| Pin 14 | DGND — Digital ground |
| Pin 15 | EOC — End-of-conversion flag |
| Pin 16 | MUX — Channel select (CH0/CH1) |
| Pin 17 | SHD — Sample-and-hold discharge control |
| Pin 18 | SHP — Sample-and-hold positive control |
| Pin 19 | AVDD — Analog +5 V supply |
| Pin 20 | NC — Not connected (per datasheet, package pin reserved) |
Typical Applications
ADC12032CIWM/NOPB is suitable for 7 applications: Digital Multimeter (DMM) Input Stage, Weigh Scale / Load-Cell Digitizer, Industrial Process Control Front End, Panel Meter and Instrumentation Display, Temperature / Pressure Sensor Conditioning, Battery-Powered Portable Instrumentation, Multi-Channel Data Acquisition Board (DAQ).
Digital Multimeter (DMM) Input Stage
The ADC12032CIWM/NOPB's 12-bit-plus-sign resolution, ±1 LSB linearity after calibration, and 2-channel MUX make it a direct fit for handheld and bench-top digital multimeter front ends. Channel 1 measures the input voltage; channel 2 can digitize the auto-zero reference to cancel thermocouple offsets and input-bias-current induced drift, which are dominant error sources in 3.5-digit DMMs. According to TI datasheet characterization, the on-chip self-calibration routine compensates zero-scale and full-scale errors against an external +2.5 V reference, so the ADC delivers the 1/2000 accuracy required for 4.5-digit multimeters without external trims. A typical circuit places 100 Ω + 100 nF RC input filters ahead of VIN+ and VIN-, with the reference node driven by a low-noise REF5025. The wide industrial -40 C to +85 C operating range and SOIC-20 wide-body footprint make hand-rework straightforward for prototype calibration.
Recommended
Weigh Scale / Load-Cell Digitizer
The ADC12032CIWM/NOPB is well suited to weigh-scale and load-cell signal-chain designs. A typical bridge-type load cell produces a bipolar output in the 0 to 30 mV range; the ADC's sign bit extends the effective input range to ±VREF, while the 2-channel input allows one channel for the load cell and one channel for a zero-scale reference to cancel temperature-induced offset drift. According to TI datasheet information, the self-calibration routine invoked at power-up trims zero-scale and full-scale errors to ±1 LSB INL. A 12-bit-plus-sign converter offers 1 part in 8,192 resolution, sufficient for commercial retail scales and laboratory balances. The MICROWIRE-compatible serial interface connects the ADC directly to a low-cost 8-bit MCU such as the MSP430, eliminating the need for an external display driver and keeping BOM cost low for high-volume scale production.
Recommended
Industrial Process Control Front End
For industrial process-control front ends, the ADC12032CIWM/NOPB's 2-channel MUX, integrated sample-and-hold, and single +5 V supply align with PLC analog-input module requirements. Channel 1 can digitize a 4-20 mA loop voltage (after sense resistor), while channel 2 monitors loop supply voltage or a local temperature sensor for cold-junction compensation. According to TI datasheet information, the wide -40 C to +85 C industrial temperature range and the SAR architecture's deterministic latency make the ADC predictable in real-time control loops. The serial MICROWIRE output supports galvanic-isolation barriers (digital isolators such as ISO1540D) for high-voltage plant isolation, simplifying the PCB layout versus a parallel-output ADC. The SOIC-20 wide-body footprint is widely accepted in industrial designs and is compatible with standard 7.5 mm SOIC land patterns.
Recommended
Panel Meter and Instrumentation Display
Panel meters, loop-powered displays, and bench-top instrumentation use the ADC12032CIWM/NOPB for low-cost high-accuracy analog-to-digital conversion. According to TI datasheet characterization, the +5 V single-supply operation eliminates the need for negative rails, and the integrated 2-channel MUX allows simultaneous voltage and current measurement on a single ADC. The on-chip self-calibration maintains specified accuracy across the industrial temperature range, important for outdoor-installed panel meters. The serial MICROWIRE-compatible interface reduces pin count and simplifies PCB routing in compact meter enclosures. The 12-bit-plus-sign resolution covers 0.1% display precision, more than adequate for most process-indicator applications. The Pb-free /NOPB finish meets current RoHS requirements for industrial equipment shipping into EU and Asia-Pacific markets.
Recommended
Temperature / Pressure Sensor Conditioning
The ADC12032CIWM/NOPB is widely used in thermocouple, RTD, and pressure-sensor signal conditioning. Channel 1 digitizes the sensor output; channel 2 measures a local cold-junction compensation sensor or a precision reference resistor to cancel temperature-induced offset and gain drift. According to TI datasheet information, the SAR architecture delivers single-shot accuracy without pipeline delay, ideal for safety-critical sensors where one misread cannot be averaged out. The integrated sample-and-hold acquires the input in a single clock cycle, simplifying input multiplexer design. The serial interface minimizes board space, and the wide industrial -40 C to +85 C temperature range handles outdoor industrial environments. The /NOPB Pb-free finish is required for medical and food-processing equipment where lead contamination is regulated.
Recommended
Battery-Powered Portable Instrumentation
Although not the lowest-power ADC on the market, the ADC12032CIWM/NOPB suits battery-powered portable instrumentation such as handheld data loggers, portable gas analyzers, and field-service tools that need more than 8-bit resolution. The single +5 V supply simplifies power-tree design: a boost converter from a single Li-ion cell, or a 4-cell alkaline stack, can power the part directly. According to TI datasheet information, the MICROWIRE serial interface allows the MCU to power-cycle the ADC between samples for additional energy savings. The wide SOIC-20 wide-body package is hand-solderable, simplifying repair in the field. The 12-bit-plus-sign resolution delivers 4-digit display precision adequate for portable instruments, and the integrated self-calibration eliminates field-trim procedures that would otherwise require opening the enclosure.
Recommended
Multi-Channel Data Acquisition Board (DAQ)
Multi-channel data acquisition cards with 2 to 8 channels can be built around the ADC12032CIWM/NOPB by paralleling multiple ADCs sharing a single MICROWIRE bus. The serial interface allows the host MCU to select which ADC is being read via independent chip-select lines, simplifying routing versus parallel-output ADCs. According to TI datasheet characterization, the SAR architecture's deterministic latency guarantees synchronized sampling when all ADCs share the same SCLK, important for vibration analysis and power-quality monitoring. The 12-bit-plus-sign resolution is sufficient for many industrial-DAQ use cases; the integrated sample-and-hold reduces external components. The wide SOIC-20 wide-body footprint and the Pb-free /NOPB finish are widely accepted in industrial-DAQ equipment.
Recommended
Recommended Products Summary
Engineering reference data for ADC12032CIWM/NOPB — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADC12032CIWM | ADC12030CIWM/NOPB | ADC12032CIWMX/NOPB | ADC10062CIWM/NOPB | ADC10158CIWMX/NOPB |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 20-SOIC (7.50 mm width) | 20-SOIC (7.50 mm width) | 20-SOIC (7.50 mm width) | 20-SOIC (7.50 mm width) | 20-SOIC (7.50 mm width) | 20-SOIC (7.50 mm width) |
| Resolution | 12-bit + sign | 12-bit + sign | 12-bit + sign | 12-bit + sign | 10-bit + sign | 10-bit |
| Architecture | SAR | SAR | SAR | SAR | SAR | SAR |
| Number of Inputs | 1 or 2 (MUX) | 1 or 2 (MUX) | 1 (single channel) | 1 or 2 (MUX) | 1 or 2 (MUX) | 8 (MUX) |
| Data Interface | MICROWIRE Serial | MICROWIRE Serial | MICROWIRE Serial | MICROWIRE Serial | MICROWIRE Serial | MICROWIRE Serial |
| Self-Calibration | Yes (offset + gain) | Yes (offset + gain) | Yes (offset + gain) | Yes (offset + gain) | Yes (offset + gain) | Yes (offset + gain) |
| Pb-Free / RoHS | Yes (/NOPB) | No (SnPb finish) | Yes | Yes | Yes | Yes |
Key Differentiators
- Built-in 2-channel analog MUX with self-calibration (vs ADC12030CIWM/NOPB)
- 12-bit-plus-sign sign-magnitude coding (vs ADC10062CIWM/NOPB)
- Self-calibration registers correct zero-scale and full-scale errors (vs External-trim potentiometer ADCs)
Design Notes
Estimated: at +5 V analog supply and ~3 mA typical operating current, the ADC12032CIWM/NOPB consumes roughly 15 mW during continuous conversions. Place 0.1 µF and 10 µF decoupling capacitors as close as possible to the AVDD and DVDD pins to suppress digital switching noise coupling into the analog front end. According to manufacturer layout guidelines, keep the analog and digital ground returns separated and join them at a single point near the ADC ground pin to prevent digital return currents from corrupting the analog signal path.
The self-calibration routine requires ~2800 clock cycles to complete; issuing a conversion command before CAL returns high may produce out-of-spec linearity. According to the manufacturer datasheet, the sign bit must be re-read together with the magnitude bits to recover the full bipolar input range - reading only the 12 magnitude bits and assuming unipolar conversion is a frequent integration mistake. Do not drive the analog input beyond ±VREF or below AGND, as the internal ESD diodes will forward-bias and degrade linearity.
Route the MICROWIRE serial traces (SCLK, DOUT, /CS, SIGN) away from the analog input traces, and place a ground guard trace between the analog and digital sections of the PCB. According to TI reference designs, the REF+ and REF- traces should be short and surrounded by ground pour to minimize reference noise pickup. The 20-SOIC wide-body footprint allows standard 7.5 mm SOIC land patterns - do not substitute a 3.81 mm SOIC-16 land pattern, the pin pitch is identical (1.54 mm) but the package width differs.
Compliance Information
/NOPB suffix indicates Pb-free, RoHS-compliant matte-tin lead plating per TI standard. NRND (Not Recommended for New Designs) lifecycle status as of 2026-10-12; not AEC-Q100 qualified - automotive designs should select an AEC-Q100 alternative.
