Analog Devices Inc./Maxim Integrated MAX1248ACEE

Overview

MAX1248ACEE from Maxim Integrated is a 10-bit, 4-channel serial analog-to-digital converter (ADC) with integrated track/hold, multiplexer, and internal 2.5V reference. It operates from +2.7V to +5.25V, supports software-configurable unipolar/bipolar and single-ended/differential inputs, and achieves 133ksps conversion rate using an external 2MHz clock. It targets portable data logging and battery-powered instrumentation where low power and compact size are critical.

For engineers reviewing the MAX1248ACEE datasheet, MAX1248ACEE pinout, MAX1248ACEE application, or MAX1248ACEE equivalent, key selection considerations include its QSOP-16 package, internal reference capability, 1.2mA active current at 133ksps, and SPI/QSPI/MICROWIRE-compatible 4-wire serial interface with SSTRB strobe output for TMS320 DSP interfacing.

Technical Context

The MAX1248ACEE uses successive-approximation architecture with a dedicated track/hold circuit that acquires input signals in ≤1.5µs. Its analog front-end supports four single-ended or two pseudo-differential input pairs (CH0/CH1, CH2/CH3), with COM pin establishing common-mode reference and ±0.5LSB stability requirement.

It features dual clock modes: external clock (2.0MHz max, drives conversion timing) and internal clock (1.8–2.25MHz, frees host processor from SAR timing constraints). The SHDN pin provides three-level control-low for full shutdown (1µA), high for internal compensation, and floating for external compensation-enabling dynamic power management between conversions.

Key Specifications

Pinout & Package

MAX1248ACEE is housed in a 16-pin QSOP package (5.3mm × 10.2mm), occupying the same PCB footprint as an 8-pin SOIC-ideal for space-constrained portable designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit serial ADC applications.

Compared with ADS7822U and MAX11100ETE+, the MAX1248ACEE uniquely balances 10-bit accuracy, internal reference flexibility, ultra-low 1µA shutdown current, and QSOP-16 compatibility with legacy SOIC footprints-making it optimal for portable, battery-limited systems requiring calibrated analog sensing without reference component overhead.

Availability

MAX1248ACEE is available at Aetrix Electronics and suitable for portable data logging, medical instrumentation, and battery-powered test equipment requiring stable component supply and long-term manufacturability.

Supply support for MAX1248ACEE 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 portable applications.

The MAX1248ACEE belongs to Maxim's low-power serial ADC product line, engineered specifically for energy-constrained, space-sensitive systems needing integrated signal conditioning, configurable input ranges, and minimal external components.

FAQ

What is the operating temperature range for the MAX1248ACEE?

The MAX1248ACEE is specified for 0°C to +70°C ambient operation, as indicated by the "C" grade suffix in its ordering code. This commercial-grade temperature range suits indoor portable instruments, data loggers, and consumer-grade medical devices where environmental extremes are not encountered. The device maintains full DC accuracy (±0.5 LSB INL, ±1 LSB DNL) and dynamic performance (66dB SINAD) across this range, with gain temperature coefficient of ±0.25 ppm/°C ensuring minimal full-scale drift.

Does the MAX1248ACEE require external passive components for stable operation?

Yes, the MAX1248ACEE requires specific external capacitors for reliable operation: a 4.7µF tantalum or aluminum electrolytic capacitor at the VREF pin (for internal reference stability), a 0.01µF ceramic capacitor at REFADJ, and a 0.1µF ceramic capacitor from each analog input (CH0–CH3) to AGND when used in differential mode. These components suppress noise, prevent reference droop, and maintain ±0.5LSB COM stability-omitting them degrades INL and introduces conversion errors, especially at higher sampling rates.

How does the SHDN pin function in the MAX1248ACEE?

The SHDN pin on the MAX1248ACEE provides three distinct power states: pulling it low enables full power-down (1µA supply current); pulling it high configures the internal reference buffer for internal compensation mode; letting it float selects external compensation mode. Unlike simple on/off shutdown, this three-level control allows dynamic optimization-e.g., floating SHDN during active conversion for best reference stability, then driving it low between samples to cut current to 1µA, achieving sub-60µA average consumption at reduced sampling rates.

Can the MAX1248ACEE interface directly with a TMS320 DSP without additional logic?

Yes, the MAX1248ACEE interfaces directly with TMS320-family DSPs via its SSTRB (serial strobe) output. In internal clock mode, SSTRB goes low at conversion start and high upon completion-providing a hardware-ready signal that triggers DMA or interrupt-driven data reads. This eliminates software polling and ensures deterministic timing alignment between analog sampling and DSP processing, a critical advantage for real-time control loops and audio preprocessing applications using the MAX1248ACEE.

What is the maximum source impedance supported by the MAX1248ACEE's analog inputs?

The MAX1248ACEE's track/hold circuit supports source impedances up to 3kΩ without performance degradation; above this, acquisition time increases per tACQ = 7.6 × (RS + 9kΩ) × 16pF. For RS > 3kΩ, a 0.01µF capacitor must be placed at each analog input to limit bandwidth and prevent settling errors. Exceeding recommended impedance without buffering causes gain error, increased INL, and potential missing codes-verified in electrical testing at TA = +25°C with fSCLK = 2MHz and VDD = 3.0V.