Analog Devices Inc./Maxim Integrated MAX1031BETI+

Overview

MAX1031BETI+ from Maxim Integrated is a 10-bit, 300ksps serial analog-to-digital converter with integrated temperature sensor (±1.2°C error over –40°C to +85°C), 16-entry FIFO, and internal 2.5V reference. It supports 16 single-ended or 8 true differential analog inputs in unipolar/bipolar modes and operates from a single +3V supply. It is used in industrial control systems for real-time sensor data acquisition with on-chip averaging and scan mode.

For engineers reviewing the MAX1031BETI+ datasheet, MAX1031BETI+ pinout, MAX1031BETI+ application, or MAX1031BETI+ equivalent, this page delivers verified specifications, package mapping, functional pin roles, real-world use cases, and validated alternative parts - all grounded in the official MAX1031 datasheet Rev 5 (8/2011) and Maxim's product documentation.

Technical Context

The MAX1031BETI+ employs a fully differential successive-approximation register (SAR) architecture with on-chip track-and-hold, supporting both single-ended and true differential input configurations. Its internal oscillator enables autonomous conversion timing in clock modes 00, 01, and 10, while clock mode 11 allows externally timed acquisitions up to 300ksps using SCLK ≤ 10MHz.

It integrates an internal temperature sensor with 1/8°C resolution and ±1.2°C accuracy over –40°C to +85°C, always referenced to its internal 2.5V reference. The 16-deep FIFO buffers ADC results and temperature readings, enabling burst acquisition without serial bus contention.

Key Specifications

Pinout & Package

The MAX1031BETI+ is packaged in a 28-pin, 5mm × 5mm TQFN with exposed pad (EP), RoHS-compliant and lead-free. The exposed pad must be soldered to GND for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multichannel, temperature-integrated ADC applications.

Compared with ADS8684IPWR and AD7928BRUZ, the MAX1031BETI+ uniquely combines 10-bit resolution, 16-channel flexibility, on-chip FIFO, internal temperature sensor, and AutoShutdown - making it optimal for space-constrained, thermally aware embedded systems requiring minimal BOM count and firmware overhead.

Availability

MAX1031BETI+ is available at Aetrix Electronics and suitable for industrial control systems, portable medical devices, and environmental data loggers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX1031BETI+ 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

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and power management ICs for demanding industrial, medical, and communications applications.

The MAX1031BETI+ belongs to Maxim's low-power, multichannel SAR ADC family engineered for embedded system supervision - integrating signal acquisition, thermal awareness, and serial interfacing in a single compact package.

FAQ

What is the operating temperature range of the MAX1031BETI+?

The MAX1031BETI+ is specified for operation from –40°C to +85°C, matching the extended industrial temperature grade. Its internal temperature sensor maintains ±1.2°C accuracy across this full range, and all DC and dynamic specifications (INL, DNL, SINAD) are guaranteed within these limits. This makes the MAX1031BETI+ suitable for deployment in harsh environments such as factory floors, outdoor infrastructure, and automotive under-hood applications.

Does the MAX1031BETI+ require an external reference voltage?

No, the MAX1031BETI+ includes a precision internal 2.5V reference with ±0.02V initial accuracy and ±30ppm/°C temperature coefficient - sufficient for most industrial and medical applications. An external differential reference can be applied via REF+ and REF− pins if higher accuracy or custom reference voltage is needed, but doing so disables the internal reference and requires additional circuitry. Temperature measurements always use the internal reference, regardless of voltage conversion configuration.

How many analog input channels does the MAX1031BETI+ support in differential mode?

The MAX1031BETI+ supports eight true differential input pairs: AIN0/AIN1, AIN2/AIN3, AIN4/AIN5, AIN6/AIN7, AIN8/AIN9, AIN10/AIN11, AIN12/AIN13, and AIN14/AIN15. This 8-channel differential capability is exclusive to the MAX1031 variant - the MAX1029 supports six differential pairs, and the MAX1027 supports only four. All differential pairs operate in either unipolar (0 to VREF) or bipolar (±VREF/2) mode, selectable per pair via the unipolar/bipolar registers.

What is the function of the FIFO in the MAX1031BETI+ and how deep is it?

The MAX1031BETI+ contains a 16-entry first-in/first-out (FIFO) buffer that stores ADC conversion results and temperature readings. Each entry holds one 10-bit result (plus status bits), allowing up to 16 consecutive conversions - including mixed voltage and temperature measurements - to be queued without MCU intervention. This enables autonomous burst acquisition in scan mode, reducing serial bus traffic and host processor load. When the FIFO overflows, new results overwrite the oldest entries.

Can the MAX1031BETI+ perform simultaneous sampling across multiple channels?

No, the MAX1031BETI+ does not support simultaneous sampling. It uses a single SAR core with a multiplexed analog front-end, sequentially converting channels in scan mode. However, its fast 300ksps rate and 16-entry FIFO allow high-throughput pseudo-simultaneous acquisition - for example, scanning all 16 channels in ~53μs (16 × 3.3μs avg conversion time). True simultaneous sampling would require multiple independent ADC cores, which the MAX1031BETI+ does not implement.