Analog Devices Inc./Maxim Integrated MAX198ACWI

Overview

MAX198ACWI from Maxim Integrated is a multirange, single +5V-supply, 12-bit data-acquisition system (DAS) with six software-programmable analog input channels, ±4V bipolar or 0V to +4.096V unipolar input range, 100ksps throughput rate, and fault protection to ±16.5V - used in industrial control systems for interfacing 4mA–20mA sensors and ±12V/±15V transducers into low-voltage embedded systems.

For engineers reviewing the MAX198ACWI datasheet, MAX198ACWI pinout, MAX198ACWI application, or MAX198ACWI equivalent, this page delivers verified technical context, real-world timing behavior, confirmed power-down modes, reference configuration options, and validated alternative parts for sensor interface design and legacy system replacement.

Technical Context

The MAX198ACWI employs successive-approximation architecture with integrated track/hold, supporting internal or external acquisition control and internal/external clock selection via control-byte bits D5–D7. Its input multiplexer is fault-protected to ±16.5V, and conversion completes in 6.0µs (typical) with 12 clock cycles.

It uses a 12-bit parallel TTL/CMOS-compatible bus (D0–D11), supports both unipolar (0V to +VREF or 0V to +VREF/2) and bipolar (±VREF or ±VREF/2) modes, and features two programmable power-down modes - STBYPD (reference buffer active) and FULLPD - with 6µA (typ) and 10µA (max) supply current in full shutdown.

Key Specifications

Pinout & Package

MAX198ACWI is housed in a 28-pin Wide SO (Small Outline) package with gull-wing leads, 300 mil body width, and standard JEDEC MS-013AC footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multirange, 12-bit data-acquisition applications.

Compared with MAX196ACWI, the MAX198ACWI trades ±10V range for tighter noise performance and optimized scaling for 4.096V-referenced industrial sensors; versus ADS7816U, it provides integrated fault protection, multirange flexibility, and parallel µP interface - reducing firmware overhead and external component count.

Availability

MAX198ACWI is available at Aetrix Electronics and suitable for industrial process monitoring, automated test equipment, medical diagnostics, and robotics requiring stable component supply across extended product lifecycles.

Supply support for MAX198ACWI 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) is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, automotive, and communications markets.

The MAX198 belongs to Maxim's legacy data-acquisition system family designed for single-supply, multirange, fault-tolerant analog digitization in harsh industrial environments - emphasizing robustness, configurability, and µP compatibility over ultra-high speed or resolution.

FAQ

What is the maximum input voltage the MAX198ACWI can tolerate without damage?

The MAX198ACWI features fault-protected analog inputs rated to ±16.5V on all six channels (CH0–CH5), even when VDD = 0V. This protection remains active in all power-down modes and does not require external clamping diodes or series resistors - enabling safe operation in noisy industrial environments with accidental wiring faults or transient surges.

Does the MAX198ACWI require an external reference, or does it include an internal one?

The MAX198ACWI includes an internal trimmed 2.50V bandgap reference amplified to 4.096V at the REF pin via the REFADJ buffer. It can operate fully standalone with this internal reference, or accept an external reference at either REF (buffer disabled) or REFADJ (buffer enabled). The internal reference is adjustable by ±1.5% using the REFADJ pin and external resistor network shown in Figure 1 of the datasheet.

How does the MAX198ACWI handle acquisition timing - internal vs. external control?

The MAX198ACWI supports both internal and external acquisition control via the ACQMOD bit (D5) in the control byte. In internal mode (ACQMOD = 0), a single WR pulse initiates a fixed 6-clock-cycle acquisition before conversion. In external mode (ACQMOD = 1), the first WR pulse starts acquisition and the second (with ACQMOD = 0) ends acquisition and triggers conversion - allowing precise aperture control for undersampling or jitter-critical applications.

What are the power-down modes supported by the MAX198ACWI, and how do they differ?

The MAX198ACWI supports two programmable power-down modes selected via PD0/PD1 bits: STBYPD (standby) keeps the internal reference buffer active for fast wake-up (<1µs), while FULLPD disables the buffer and reduces supply current to ≤10µA. Both modes preserve register state and maintain input fault protection. Power-down takes effect only after conversion completion, ensuring no data loss during transition.

Is the MAX198ACWI pin-compatible with other devices in the MAX196/MAX198 family?

Yes - the MAX198ACWI shares identical pinout, timing, and interface behavior with all MAX196/MAX198 variants in the same package (e.g., MAX196ACWI, MAX198BCWI). Differences are limited to input range specification (±4V vs. ±10V), grade (C-grade = 0°C to +70°C), and package type (Wide SO for ACWI suffix). No PCB layout changes are needed when substituting within the same package variant.