Analog Devices Inc./Maxim Integrated MAX172BEWG

Overview

MAX172BEWG 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 MAX172BEWG datasheet, MAX172BEWG pinout, MAX172BEWG application, or MAX172BEWG equivalent, key selection considerations include its 12-bit resolution, single-supply operation, on-chip reference accuracy, and compatibility with microcontroller SPI-compatible digital interfaces.

Technical Context

The MAX172BEWG employs a successive-approximation register (SAR) architecture with an internal sample-and-hold amplifier and precision bandgap voltage reference. It uses a serial 3-wire interface compatible with SPI modes 0 and 3 for data readout and control.

Conversion timing is controlled by an internal 2.5MHz clock generator; no external clock is required. The device supports unipolar input ranges of 0V to V_REF or 0V to 2×V_REF, where V_REF is internally fixed at 2.5V or externally adjustable.

Key Specifications

Pinout & Package

MAX172BEWG is housed in a 24-pin wide SOIC (SO24) package with 0.300-inch body width and standard JEDEC MS-013AC footprint.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822U and MAX1112CPE+, the MAX172BEWG offers deterministic conversion initiation via dedicated CONVST, making it better suited for synchronized multi-channel sampling systems where precise timing control is critical.

Availability

MAX172BEWG is available at Aetrix Electronics and suitable for industrial process monitoring, medical instrumentation, and test equipment requiring stable component supply and long-term production continuity.

Supply support for MAX172BEWG 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 MAX172BEWG belongs to Maxim's high-accuracy data acquisition ADC family, engineered for applications demanding reliable 12-bit performance with minimal external components and single-supply simplicity.

FAQ

What is the maximum sampling rate of the MAX172BEWG?

The MAX172BEWG achieves a maximum sampling rate of 100 kSPS. This rate is supported by its internal 2.5MHz clock generator and optimized SAR architecture. At this speed, the MAX172BEWG maintains guaranteed ±1 LSB INL and DNL across its full operating temperature range. System-level timing must account for CONVST pulse width and serial readout duration.

Does the MAX172BEWG require an external reference voltage?

No, the MAX172BEWG includes an internal 2.5V bandgap reference and operates fully with that default. However, the REF pin can accept an external reference between 1.0V and 5.0V to adjust full-scale input range. When using the internal reference, no external components are needed-this simplifies design and improves stability over temperature and time compared to discrete references.

What digital interface does the MAX172BEWG use?

The MAX172BEWG uses a 3-wire serial interface compatible with SPI modes 0 and 3. It requires CS, DIN, DOUT, and CLK signals-no parallel bus or additional handshaking lines. The interface transmits 12-bit conversion results MSB-first and accepts configuration bits (e.g., input range selection) before conversion starts. This reduces MCU pin count and PCB routing complexity versus parallel-output ADCs.

Is the MAX172BEWG pin-compatible with other Maxim ADCs like the MAX170 or MAX171?

No, the MAX172BEWG is not pin-compatible with the MAX170 or MAX171. While all three are 12-bit SAR ADCs, they differ in pin count (MAX170/MAX171 are 20-pin), pin functions (e.g., missing dedicated CONVST on MAX170), and package type. The MAX172BEWG's 24-pin SOIC layout and specific signal assignments-including separate AGND/DGND and CONVST-are unique to its datasheet-defined footprint and cannot be substituted without PCB revision.

What is the purpose of the CONVST pin on the MAX172BEWG?

CONVST is a dedicated convert-start input that triggers the sample-and-hold acquisition phase independently of the serial interface. A rising edge on CONVST initiates sampling; conversion proceeds automatically thereafter. This allows precise synchronization with external events (e.g., sensor excitation pulses or system clocks), enabling deterministic timing control not possible with CS-edge-initiated alternatives like the MAX1112CPE+.