Texas Instruments ADC08831IMX

Overview

ADC08831IMX from Texas Instruments is an 8-bit successive-approximation analog-to-digital converter with integrated 2-channel analog multiplexer, track/hold function, and 3-wire serial MICROWIRE-compatible interface. It operates from a single 5V supply, delivers ±1 LSB total unadjusted error, and achieves up to 181 ksps sampling rate at 2 MHz clock. It is used in embedded sensor digitization where low pin count, noise immunity, and software-configurable input modes are required.

For engineers reviewing the ADC08831IMX datasheet, ADC08831IMX pinout, ADC08831IMX application, or ADC08831IMX equivalent, key selection considerations include its fixed-polarity differential input configuration, VREF pin availability, MSB-first serial output format, and SOIC/VSSOP-8 package compatibility with legacy ADC0831 designs.

Technical Context

The ADC08831IMX implements a successive-approximation register (SAR) architecture with an on-chip ratioed capacitor array and resistor ladder for bit-weighting. Its analog front-end includes a built-in sample-and-hold that acquires the voltage difference between designated +IN and −IN terminals during conversion.

It supports only one differential input pair (CH0+/CH1−) with fixed polarity-no MUX addressing required-and uses a 3-wire serial interface (CS, CLK, DI/DO) compliant with MICROWIRE timing. The VREF pin is externally accessible, enabling ratiometric or absolute reference configurations independent of VCC.

Key Specifications

Pinout & Package

ADC08831IMX is available in 8-pin SOIC (D) and VSSOP (DGK) packages, both surface-mount, with identical pin assignments and thermal characteristics (θJA = 235°C/W for SOIC, 122°C/W for VSSOP).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit serial ADC applications.

Compared with ADC0831IMX, ADC08831IMX adds VREF configurability and tighter error spec; compared with ADS7822U, it trades resolution and speed for lower power, smaller footprint, and simpler integration in legacy 8-bit systems.

Availability

ADC08831IMX is available at Aetrix Electronics and suitable for industrial process monitoring, embedded sensor digitization, remote analog signal acquisition, and noise-resilient instrumentation requiring stable component supply and long-term sourcing continuity.

Supply support for ADC08831IMX includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity technologies, with decades of expertise in precision data converters and industrial-grade ICs.

The ADC08831IMX belongs to TI's legacy 8-bit serial ADC family designed for cost-effective, low-pin-count digitization in resource-constrained embedded systems - emphasizing ease of integration, noise immunity, and production-ready accuracy.

FAQ

What is the maximum clock frequency supported by ADC08831IMX?

The ADC08831IMX supports a maximum clock frequency of 2 MHz, as specified in its operating ratings. At this frequency, the device achieves a maximum conversion time of 4 μs and a sampling rate of up to 181 ksps. Operation above 2 MHz is not guaranteed and may result in timing violations or increased error; the clock duty cycle must remain between 40% and 60% for reliable performance across the full −40°C to +85°C temperature range.

Does ADC08831IMX support single-ended input mode?

No, ADC08831IMX does not support configurable single-ended input mode. Unlike the ADC08832, it implements a fixed differential input configuration with IN+ assigned to channel 0 and IN− to channel 1. This eliminates MUX addressing overhead but restricts usage to true differential or pseudo-differential signal acquisition - single-ended operation requires external level-shifting or biasing to meet the differential input requirement.

Can ADC08831IMX be used with a 3.3V microcontroller interface?

Yes, ADC08831IMX can interface with 3.3V microcontrollers, but only if VCC is supplied at 3.3V - its digital I/O is TTL/CMOS compatible and operates down to 4.5V minimum per datasheet, so 3.3V operation falls outside specification. For 3.3V systems, use level translation on CS, CLK, and DI/DO lines, or select a modern 3.3V-native ADC. The analog input range scales with VCC, so 3.3V supply yields 0–3.3V full-scale range.

What is the purpose of the VREF pin on ADC08831IMX?

The VREF pin on ADC08831IMX defines the full-scale voltage span (VIN+ − VIN−) for conversion - 1 LSB equals VREF/256. It enables either ratiometric operation (e.g., tying VREF to VCC for sensor systems where supply and signal track together) or absolute accuracy (e.g., connecting a stable 2.5V reference for precise transducer measurement). Unlike ADC08832, ADC08831IMX retains full VREF control, supporting reduced-span inputs without sacrificing resolution.

How does ADC08831IMX enter low-power mode?

ADC08831IMX enters low-power mode automatically when the CS pin is driven HIGH. In this state, analog circuitry and digital logic transition to static low-current modes, power dissipation drops to 3.0 mW typical, and the DO output enters TRI-STATE. To minimize static current, all digital inputs (CLK, CS, DI) should be driven at voltages matching VCC - mismatched logic levels (e.g., 2.4V into 5V VCC) cause unnecessary CMOS buffer leakage.