Analog Devices Inc./Maxim Integrated MAX194BEWE+

Overview

MAX194BEWE+ from Maxim Integrated is a 14-bit successive-approximation analog-to-digital converter (ADC) with 85ksps throughput, ±1⁄2 LSB integral nonlinearity (INL), 82dB SINAD, 9.4µs conversion time, and 10µA shutdown current. It features internal calibration, capacitive-DAC-based track/hold, and pin-selectable unipolar (0V to VREF) or bipolar (–VREF to VREF) input range - used in portable instrumentation and vibration analysis systems requiring high DC accuracy and low power.

For engineers reviewing the MAX194BEWE+ datasheet, MAX194BEWE+ pinout, MAX194BEWE+ application, or MAX194BEWE+ equivalent, this page delivers verified electrical specs, package mapping to 16-pin wide SO, functional pin roles, real-world use cases, and two validated alternative ADCs for signal chain design and BOM optimization.

Technical Context

The MAX194BEWE+ implements a SAR architecture with a binary-weighted capacitive DAC and ten dedicated calibration DACs that digitally correct MSB capacitor mismatches. Calibration occurs automatically on power-up or via RESET, requiring ~8.2ms at 1.7MHz CLK and storing correction codes in nonvolatile logic.

It supports dual serial readout modes: synchronous bit-by-bit output during conversion (at CLK rate) or asynchronous post-conversion streaming (at up to 5MHz SCLK). Input acquisition is inherently handled by the DAC array, requiring no external track/hold circuitry - with four CLK cycles allocated per sample.

Key Specifications

Pinout & Package

The MAX194BEWE+ is housed in a 16-pin wide SO (Small Outline) package, RoHS-compliant, with 1.27mm pitch and gull-wing leads. Thermal pad not present; standard JEDEC MS-013AC outline.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 14-bit SAR ADC applications.

Compared with ADS8325IPW and AD7892BRZ, the MAX194BEWE+ uniquely combines 14-bit accuracy with factory-trimmed calibration, pin-selectable input range, and ultra-low shutdown current - making it optimal for portable, battery-constrained, and thermally variable measurement systems where DC integrity is non-negotiable.

Availability

MAX194BEWE+ is available at Aetrix Electronics and suitable for portable instrumentation, vibration analysis, medical signal acquisition, industrial controls, and robotics requiring stable component supply across extended temperature ranges.

Supply support for MAX194BEWE+ 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 demanding industrial, medical, and communications applications.

The MAX194BEWE+ belongs to Maxim's high-accuracy data acquisition product line, engineered specifically for portable and embedded systems needing calibrated 14-bit performance without external trimming or complex support circuitry.

FAQ

What is the operating temperature range for the MAX194BEWE+?

The MAX194BEWE+ is rated for –40°C to +85°C, matching the "E" grade specification. This extended industrial temperature range ensures reliable 14-bit INL and SINAD performance in harsh environments such as factory floors or outdoor instrumentation - unlike the "C" grade (0°C to +70°C) versions. All calibration and dynamic specifications in the datasheet apply across this full range.

Does the MAX194BEWE+ require an external reference voltage?

Yes, the MAX194BEWE+ requires an external reference voltage applied to the REF pin (Pin 12), with a range of 0V to VDDA (+5V). It does not include an internal reference. For full 14-bit accuracy, a low-drift, low-noise reference such as the MAX6241 (1ppm/°C) with proper bypassing (1µF low-ESR + 0.1µF ceramic) is recommended - especially in bipolar mode where REF noise directly impacts common-mode rejection.

How does the MAX194BEWE+ achieve ±1⁄2 LSB INL without external calibration?

The MAX194BEWE+ achieves ±1⁄2 LSB INL using an on-chip auto-calibration system that measures and digitally corrects capacitor mismatches in its main DAC array. During power-up or RESET, it performs ~14,000 CLK-cycle calibration sequences, stores correction codes in logic registers, and applies them dynamically during conversion - eliminating need for manual trims or system-level calibration routines while maintaining spec across –40°C to +85°C.

Can the MAX194BEWE+ interface directly with an SPI host controller?

Yes, the MAX194BEWE+ supports SPI-compatible serial communication via CS, SCLK, and DOUT pins. It operates in Mode 0 (CPOL = 0, CPHA = 0) and Mode 1 (CPOL = 0, CPHA = 1), with data latched on rising or falling SCLK edges. The EOC pin provides framing synchronization, and CS enables three-state DOUT - allowing direct connection to standard SPI peripherals without level-shifting or glue logic.

What is the purpose of the BP/UP/SHDN pin on the MAX194BEWE+?

The BP/UP/SHDN pin (Pin 1) serves three distinct functions: floating = bipolar input range (–VREF to VREF); +5V = unipolar input range (0V to VREF); 0V = 10µA shutdown mode. This single-pin configurability eliminates external logic or jumpers, simplifying design for multi-range sensor interfaces and enabling rapid power-state transitions without firmware overhead - a key advantage in portable MAX194BEWE+ deployments.