Analog Devices Inc./Maxim Integrated MAX189CCWE+T

Overview

MAX189CCWE+T from Maxim Integrated is a 12-bit successive-approximation analog-to-digital converter (ADC) operating from a single +5V supply, accepting 0–5V unipolar analog input with 75ksps throughput and requiring an external 4.096V reference voltage. It features an on-chip track/hold, 3-wire SPI/QSPI/MICROWIRE-compatible serial interface, and shutdown mode drawing ≤10µA. It targets low-power sensor digitization in portable instrumentation and isolated data acquisition.

For engineers reviewing the MAX189CCWE+T datasheet, MAX189CCWE+T pinout, MAX189CCWE+T application, or MAX189CCWE+T equivalent, key selection criteria include external reference dependency, 16-pin wide SO package compatibility, 1.0–2.0mA operating current, ±1 LSB integral nonlinearity (MAX189A grade), and 70dB SINAD at 10kHz input - all critical for precision, low-power embedded ADC design.

Technical Context

The MAX189CCWE+T implements a 12-bit SAR architecture with integrated track/hold, acquiring input signals in 1.5µs and completing conversion in 5.5–8.5µs. Its serial interface operates without external hardware, using only CS, SCLK, and DOUT lines with full compatibility to SPI, QSPI, and MICROWIRE protocols at clock rates up to 5MHz.

Unlike the MAX187, the MAX189CCWE+T lacks an internal reference and requires an external 4.096V source applied to the REF pin, with specified accuracy maintained for reference voltages between +2.5V and VDD. Shutdown is controlled via the SHDN pin, reducing supply current to ≤10µA while enabling wake-up in <2µs when external reference remains stable.

Key Specifications

Pinout & Package

MAX189CCWE+T is housed in a 16-pin wide SO (SOIC-W) package with exposed pad (not electrically connected), measuring 10.3 mm × 7.5 mm × 2.65 mm. Pin 1 is marked by a beveled corner; pins 2, 4, 5, 7, 9, 13, and 14 are NC and recommended tied to AGND for noise reduction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7816U and AD7893ARZ-10, the MAX189CCWE+T offers superior flexibility in reference selection (2.5V–5.25V), lower operating current (1.0–2.0mA vs. 2.5mA typical), and dedicated SHDN pin for deterministic low-power sequencing - making it optimal for externally referenced, ultra-low-quiescent designs.

Availability

MAX189CCWE+T is available at Aetrix Electronics and suitable for portable data logging, remote DSP, isolated data acquisition, and high-accuracy process control requiring stable component supply across industrial temperature ranges (–40°C to +85°C) and long-term production continuity.

Supply support for MAX189CCWE+T 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 MAX189CCWE+T belongs to Maxim's legacy low-power serial ADC product line, engineered specifically for space- and power-constrained systems needing high-resolution digitization with minimal external components and robust serial interoperability.

FAQ

What reference voltage does the MAX189CCWE+T require?

The MAX189CCWE+T requires an external reference voltage applied to the REF pin, specified between +2.5V and VDD (4.75–5.25V). For full 12-bit accuracy and standard full-scale range, a precision 4.096V reference is recommended. The device draws up to 350µA from the reference during conversion, and the REF pin must be bypassed with at least a 0.1µF capacitor placed close to the pin. Unlike the MAX187, the MAX189CCWE+T has no internal reference circuitry.

What is the operating temperature range for the MAX189CCWE+T?

The MAX189CCWE+T is rated for operation from –40°C to +85°C (industrial grade), as indicated by the "E" suffix in its full ordering code. This range is validated across all electrical specifications including INL, SINAD, and supply current. The device maintains ±1 LSB integral nonlinearity and 70dB SINAD throughout this temperature span when used with a stable external reference and proper PCB layout practices.

How does the MAX189CCWE+T interface with an SPI host controller?

The MAX189CCWE+T interfaces with SPI hosts using CPOL = 0 and CPHA = 0 configuration. A falling edge on CS initiates conversion; DOUT goes low during conversion and rises to signal end-of-conversion (EOC). Data is clocked out MSB-first on SCLK's falling edge, requiring exactly 13 clock cycles (1 leading '1' + 12 data bits). No additional framing or command bytes are needed, and the interface operates reliably at clock rates up to 5MHz.

Can the MAX189CCWE+T be used in a multiplexed analog input system?

Yes, the MAX189CCWE+T supports multiplexed inputs via its 1.5µs track/hold acquisition time and 16pF input capacitance. To maintain accuracy, the analog source impedance should be ≤5kΩ; higher impedances require longer acquisition intervals per the formula tACQ = 9(RS + 5kΩ)·16pF. A dedicated op-amp buffer per channel is recommended for high-impedance sensors, and CS must be pulsed for each new channel conversion.

What is the shutdown behavior of the MAX189CCWE+T?

Pulling the SHDN pin low places the MAX189CCWE+T into shutdown mode, reducing supply current to ≤10µA. The device retains no state and requires a minimum wake-up time of <2µs before initiating a new conversion - assuming the external reference remains powered and stable. During shutdown, DOUT enters high-impedance state, and the track/hold is disabled. SHDN may be left floating or driven high to maintain normal operation.