Analog Devices Inc./Maxim Integrated MAX172ACNG

Overview

MAX172ACNG from Maxim Integrated is a 12-bit successive-approximation analog-to-digital converter (ADC) with internal track/hold, reference, and clock. It operates from a single +5V supply, achieves 100ksps sampling rate, and features ±1 LSB integral nonlinearity. It is used in data acquisition systems requiring medium-speed, high-resolution digitization of analog sensor signals.

For engineers reviewing the MAX172ACNG datasheet, MAX172ACNG pinout, MAX172ACNG application, or MAX172ACNG equivalent, key selection considerations include its 12-bit resolution, single-supply operation, on-chip reference accuracy (±0.5% initial), and compatibility with microcontroller parallel interfaces for embedded measurement systems.

Technical Context

The MAX172ACNG employs a successive-approximation register (SAR) architecture with internal sample-and-hold, eliminating external hold circuitry. It integrates a precision 2.5V bandgap reference with ±0.5% initial tolerance and low temperature drift (25ppm/°C).

Conversion is initiated by a WR pulse, and completion is signaled via the BUSY output. Data is output in straight binary format on an 8-bit multiplexed bus, requiring two read cycles to retrieve the full 12-bit result.

Key Specifications

Pinout & Package

MAX172ACNG is housed in a 28-pin plastic DIP (dual in-line package) with 0.6-inch body width and 0.1-inch pin spacing.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX172ACNG, the ADS7822U trades resolution and parallel interface for compact serial communication, while the MAX195BCNG+ maintains identical form factor and speed but delivers four additional bits of dynamic range-critical for low-amplitude signal fidelity in upgraded instrumentation.

Availability

MAX172ACNG is available at Aetrix Electronics and suitable for industrial process monitoring, test equipment development, and medical instrumentation requiring stable component supply and long-lifecycle support.

Supply support for MAX172ACNG 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 and mixed-signal ICs for industrial, medical, and communications applications.

The MAX172ACNG belongs to Maxim's legacy high-accuracy ADC product line, engineered for embedded data acquisition where resolution, integration, and single-supply simplicity are prioritized over ultra-high speed.

FAQ

What is the maximum sampling rate of the MAX172ACNG?

The MAX172ACNG achieves a maximum sampling rate of 100ksps. This rate is guaranteed under specified operating conditions including V_DD = +5V, T_A = 0°C to +70°C, and proper decoupling. Each conversion completes within 10μs, enabling reliable capture of signals with bandwidths up to 50kHz per Nyquist criterion. The MAX172ACNG does not support higher rates even with optimized timing.

Does the MAX172ACNG require an external reference voltage?

No, the MAX172ACNG includes an internal 2.5V bandgap reference with ±0.5% initial accuracy and 25ppm/°C temperature coefficient. This reference is accessible at the REF pin and may be overdriven if an external reference is preferred. Using the internal reference eliminates component count and layout sensitivity, making the MAX172ACNG self-contained for most medium-precision applications.

How is 12-bit data read from the MAX172ACNG?

The MAX172ACNG uses an 8-bit multiplexed bus: the lower 8 bits appear on AD0–AD7, and the upper 4 bits appear on DB0–DB3. Reading the full 12-bit result requires two consecutive read cycles-first retrieving AD0–AD7, then DB0–DB3-controlled by the RD signal. This architecture reduces I/O pin count but mandates precise timing coordination in the host firmware for the MAX172ACNG.

What package type is used for the MAX172ACNG?

The MAX172ACNG is supplied in a 28-pin plastic DIP (dual in-line package) with 0.6-inch body width and 0.1-inch pin pitch. This through-hole package supports prototyping, legacy industrial systems, and applications requiring mechanical robustness and hand-solderability. The MAX172ACNG is not offered in SOIC or surface-mount variants.

Is the MAX172ACNG pin-compatible with other Maxim ADCs like the MAX170 or MAX171?

No, the MAX172ACNG is not pin-compatible with the MAX170 or MAX171. Although all three are 12-bit SAR ADCs in 28-pin DIP packages, their pin assignments differ significantly-for example, BUSY and RD functions are assigned to different pins, and the data bus structure varies. Interchangeability would require PCB redesign. Always verify pinout against the specific MAX172ACNG datasheet before substitution.