Analog Devices Inc./Maxim Integrated MAX1239MEEE

Overview

MAX1239MEEE from Maxim Integrated is a 12-bit, 12-channel, low-power analog-to-digital converter with integrated track/hold, 2.048V internal reference, I²C-compatible 2-wire serial interface, and operation from 2.7V to 3.6V supply. It delivers 94.4ksps throughput, ±1 LSB INL, and supports software-configurable unipolar/bipolar and single-ended/differential input modes for precision sensor and battery-powered measurement systems.

For engineers reviewing the MAX1239MEEE datasheet, MAX1239MEEE pinout, MAX1239MEEE application, or MAX1239MEEE equivalent, key selection criteria include its 12-channel analog multiplexer, internal 2.048V reference accuracy (±80mV over temperature), 1.7MHz high-speed I²C mode, AutoShutdown™ current reduction to <1µA, and QSOP-16 package compatibility with industrial and portable instrumentation designs.

Technical Context

The MAX1239MEEE employs successive-approximation architecture with fully differential track/hold circuitry and a switched-capacitor DAC. Its analog front-end supports 12 single-ended or 6 fully differential input channels, configurable via CS[3:0] bits in the setup register, with acquisition time dependent on source impedance and clock mode.

It operates exclusively in I²C slave mode with factory-programmed 7-bit slave address 0x67 (0110111), supports Fast Mode (400kHz) and High-Speed Mode (1.7MHz), and uses internal clocking (2.8MHz) or external SCL as conversion trigger - with aperture delay of 30ns in HS-mode and 800ns in Fast Mode.

Key Specifications

Pinout & Package

MAX1239MEEE is housed in a 16-pin QSOP package (5.3mm × 10.2mm, 0.65mm pitch), specified for –40°C to +85°C operation. Pin functions are electrically validated per Maxim's official datasheet Rev 4 (19-2333).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit multichannel ADC applications.

Compared with MAX1239MEEE, ADS7953IRHBT offers more channels but demands external reference and SPI routing, while AD7946BRUZ delivers higher resolution at the cost of 5V-only operation and no I²C support - making MAX1239MEEE optimal for compact, battery-efficient, I²C-native 12-bit sensor systems.

Availability

MAX1239MEEE is available at Aetrix Electronics and suitable for portable medical devices, battery-powered environmental sensors, industrial PLC analog input modules, and handheld test equipment requiring stable component supply across extended temperature ranges.

Supply support for MAX1239MEEE 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) is a semiconductor company specializing in precision analog, mixed-signal, and power management ICs for demanding industrial, medical, and communications applications.

The MAX1236–MAX1239 family was designed for low-power, multichannel data acquisition in space-constrained, battery-sensitive systems - emphasizing integration of reference, T/H, and I²C interface to reduce bill-of-materials and layout complexity.

FAQ

What is the factory-programmed I²C slave address for MAX1239MEEE?

The MAX1239MEEE has a fixed 7-bit I²C slave address of 0x67 (binary 0110111), as confirmed in the Ordering Information table of the official datasheet Rev 4. This address is laser-trimmed at wafer test and cannot be modified. When initiating communication, the master must send this address followed by the R/W bit (0 for write, 1 for read) to access MAX1239MEEE registers.

Does MAX1239MEEE support both internal and external reference configurations simultaneously?

No, MAX1239MEEE does not support simultaneous internal and external reference use. The device selects either the internal 2.048V reference or an external reference (1V to VDD) via the SEL[2:1] bits in the setup register. When internal reference is enabled, AIN3/REF and AIN11/REF function as analog inputs; when external reference is selected, those pins become reference inputs - exclusive mode operation is enforced by hardware design.

How does AutoShutdown™ affect conversion timing in MAX1239MEEE?

AutoShutdown™ powers down the MAX1239MEEE between conversions, reducing supply current to <1µA, but introduces a wake-up latency of one internal clock cycle (~357ns at 2.8MHz) before acquisition begins. This delay is negligible at low throughput rates (<1ksps) but must be accounted for in time-critical applications; the device remains fully responsive to I²C commands during shutdown, allowing immediate reactivation via new read/write cycles.

Can MAX1239MEEE perform true differential measurements across arbitrary channel pairs?

Yes, MAX1239MEEE supports true fully differential measurements using predefined channel pairs: AIN0–AIN1, AIN2–AIN3, AIN4–AIN5, AIN6–AIN7, AIN8–AIN9, and AIN10–AIN11. These pairings are hardwired in the analog multiplexer and selected via CS[3:0] bits in differential mode (SGL/DIF = 0). Cross-pair combinations (e.g., AIN0–AIN5) are not supported - the differential path is fixed per datasheet Table 4.

What is the maximum source impedance allowable for accurate sampling with MAX1239MEEE?

MAX1239MEEE maintains full 12-bit accuracy with analog source impedances up to 1.5kΩ, as verified in the Electrical Characteristics table. For sources exceeding 1.5kΩ, sampling error increases due to incomplete CT/H charging within the acquisition window; mitigation requires either adding a 100pF capacitor from input to GND or using an external buffer amplifier - both approaches are documented in the "Analog Input and Track/Hold" section of the datasheet.