Analog Devices Inc./Maxim Integrated MAX1229ACEP+

Overview

The MAX1229ACEP+ from Maxim Integrated is a 12-bit, 300ksps serial analog-to-digital converter with integrated temperature sensor (±0.7°C accuracy), 16-entry FIFO, internal 2.5V reference, and SPI/QSPI/MICROWIRE-compatible 3-wire interface. It supports 12 single-ended or 6 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 voltage and temperature monitoring of sensor arrays.

For engineers reviewing the MAX1229ACEP+ datasheet, MAX1229ACEP+ pinout, MAX1229ACEP+ application, or MAX1229ACEP+ equivalent, this page delivers verified technical context, exact pin functions, confirmed operating parameters, and validated alternative parts - all specific to the MAX1229ACEP+ QSOP-20 package and extended -40°C to +85°C grade.

Technical Context

The MAX1229ACEP+ implements a fully differential successive-approximation register (SAR) ADC architecture with on-chip track-and-hold, supporting both single-ended and true differential input configurations. Its internal oscillator enables autonomous scan mode operation without external timing control.

It integrates a dedicated temperature-sensing path using the same internal reference and conversion core, delivering 1/8°C resolution in two's complement format. The 16-deep FIFO buffers conversion results and temperature readings independently, decoupling acquisition from serial readout to reduce µP bus contention.

Key Specifications

Pinout & Package

MAX1229ACEP+ is packaged in a 20-pin QSOP (0.154" wide), RoHS-compliant, lead-free package with standard JEDEC footprint and moisture sensitivity level MSL-1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multichannel ADC applications.

Compared with ADS7953IRHBT and AD7490BRUZ, the MAX1229ACEP+ uniquely combines FIFO buffering, on-die temperature sensing, and internal reference in a 20-pin QSOP - reducing component count and layout area for space-constrained industrial and medical edge nodes.

Availability

MAX1229ACEP+ is available at Aetrix Electronics and suitable for industrial process monitoring, patient vital sign acquisition, environmental data logging, and motor drive current feedback requiring stable component supply across extended temperature ranges.

Supply support for MAX1229ACEP+ 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 industrial, medical, and communications applications.

The MAX1229ACEP+ belongs to the MAX1227/MAX1229/MAX1231 family - engineered for low-power, multichannel data acquisition in space- and cost-constrained systems requiring integrated reference and thermal awareness.

FAQ

What is the operating temperature range for the MAX1229ACEP+?

The MAX1229ACEP+ is specified for operation from -40°C to +85°C, matching the "E" grade in Maxim's ordering nomenclature. This extended industrial temperature range ensures reliable performance in harsh environments such as factory automation cabinets and outdoor instrumentation enclosures. All key specifications-including INL, DNL, reference stability, and temperature sensor accuracy-are guaranteed across this full range.

Does the MAX1229ACEP+ require an external reference voltage?

No, the MAX1229ACEP+ includes a precision internal 2.5V reference (2.48V to 2.52V, ±30ppm/°C TC) that can be used directly for all conversions. An external differential reference may be applied via REF+ and REF-/AIN10 pins if higher accuracy or custom full-scale range is needed-but doing so disables the internal temperature sensor, as it relies exclusively on the internal reference.

How many analog input channels does the MAX1229ACEP+ support?

The MAX1229ACEP+ supports 12 single-ended analog inputs (AIN0–AIN11) or 6 true differential input pairs (e.g., AIN0/AIN1, AIN2/AIN3, ..., AIN10/AIN11). Channel configuration is controlled via the setup and conversion registers. Note that AIN10 and AIN11 are shared with REF- and CNVST functions, respectively-only one function per pin is active at a time.

What is the purpose of the FIFO in the MAX1229ACEP+?

The 16-entry FIFO in the MAX1229ACEP+ stores completed conversion results-including up to 15 voltage samples and one temperature reading-allowing the host µP to initiate multiple acquisitions (e.g., scan mode or averaging) without waiting for each result. This decouples conversion timing from serial readout, reducing bus contention and enabling deterministic latency in real-time control loops.

Can the MAX1229ACEP+ measure temperature and analog voltage simultaneously?

Yes, the MAX1229ACEP+ can perform concurrent temperature and voltage measurements. A temperature reading is triggered by setting the TEMP bit in the conversion register; it occupies one FIFO slot and is always returned first upon readout. Voltage conversions proceed in parallel using the same internal reference and SAR core, with results stored in remaining FIFO entries - enabling synchronized thermal-aware data acquisition.