Analog Devices Inc./Maxim Integrated MAX1232CWE+

Overview

MAX1232CWE+ from Maxim Integrated is a microprocessor supervisory circuit that monitors +5V power supply voltage, provides 250ms reset pulse width, implements programmable watchdog timeout (150ms/600ms/1.2s), and features debounced manual reset input - all in a 16-pin wide SO package for industrial controllers and embedded systems requiring reliable power-up sequencing and software execution monitoring.

For engineers reviewing the MAX1232CWE+ datasheet, MAX1232CWE+ pinout, MAX1232CWE+ application, or MAX1232CWE+ equivalent, this page delivers verified functional specifications, validated pin roles, confirmed voltage trip thresholds (4.62V @5%, 4.37V @10%), and real-world use context for μP reset supervision in temperature-stable environments (0°C to +70°C).

Technical Context

The MAX1232CWE+ integrates three core supervision functions: precision VCC detection with digitally selectable 5% or 10% tolerance (via TOL pin), a falling-edge-triggered watchdog timer with three timeout modes set by TD pin voltage (GND/open/VCC), and a debounced pushbutton reset input (PBRST) that guarantees recognition of ≥20ms low pulses while ignoring <1ms glitches.

It delivers dual active-reset outputs: RST (active-high, push-pull) and RST (active-low, open-drain), enabling direct interface with both standard logic and pull-up–dependent microcontroller reset inputs. No external components are required for basic operation, and internal 40kΩ PBRST pull-up eliminates need for external biasing.

Key Specifications

Pinout & Package

MAX1232CWE+ is housed in a 16-pin wide SO (small-outline) package with 0.300" body width and standard 0.050" pitch. Pin 1 is located at top-left corner when notch faces up; pins are numbered counter-clockwise.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with MAX1232CSA+, the MAX1232CWE+ offers identical supervision functionality in a wider SO package optimized for thermal dissipation and routing clarity; compared with TPS3808G33DBVR, it supports 5V systems, provides selectable thresholds and watchdog modes, and delivers dual reset outputs - making it uniquely suited for legacy 5V μP upgrades and multi-rail designs.

Availability

MAX1232CWE+ is available at Aetrix Electronics and suitable for industrial controllers, embedded data loggers, and medical diagnostic instruments requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX1232CWE+ 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, communications, and computing applications.

The MAX1232 product line delivers highly integrated microprocessor supervision with ultra-low power, programmable timing, and dual-output reset capability - engineered specifically for reliability-critical 5V embedded systems.

FAQ

What is the operating temperature range for the MAX1232CWE+?

The MAX1232CWE+ is rated for operation from 0°C to +70°C, as indicated by the "C" suffix in its part number. This commercial-grade temperature range makes it suitable for indoor industrial equipment, office automation devices, and non-automotive embedded systems where ambient conditions remain within this band. The device's electrical characteristics, including reset threshold accuracy and watchdog timing, are fully specified across this entire range.

How does the MAX1232CWE+ select between 5% and 10% VCC tolerance?

The MAX1232CWE+ selects VCC tolerance using the TOL pin: connect TOL to GND for a 5% trip point (typically 4.62V), or to VCC for a 10% trip point (typically 4.37V). This digital selection eliminates external resistor networks and allows field-configurable reset thresholds without hardware changes. The actual trip voltage is guaranteed between 4.50V–4.74V (5% mode) and 4.25V–4.49V (10% mode) over temperature and supply variation.

Does the MAX1232CWE+ require external components to function?

No, the MAX1232CWE+ requires no external components for core supervision functionality. Its internal voltage reference, watchdog oscillator, debounce logic, and pull-up on PBRST enable full operation with only VCC, GND, and connections to RST, RST, ST, TD, TOL, and PBRST. External pull-ups are needed only for the open-drain RST output, and optional RC filters may be added for noise immunity - but these are not mandatory for specification compliance.

What is the function of the TD pin on the MAX1232CWE+?

The TD pin on the MAX1232CWE+ configures the watchdog timer timeout period: grounding TD selects 150ms, leaving TD open selects 600ms, and connecting TD to VCC selects 1.2s. This pin directly controls the internal timebase without external timing components. The timeout is measured from the last ST falling edge; if ST is not strobed within the selected period, RST and RST assert for ≥250ms to force μP reset.

Can the MAX1232CWE+ replace the DS1232 in existing designs?

Yes, the MAX1232CWE+ is explicitly designed as a plug-in upgrade for the Dallas DS1232, offering identical pinout in compatible packages (including 16-pin wide SO), same functional behavior, and improved performance - notably 1/10th the supply current and enhanced noise immunity. No PCB modifications are required when replacing DS1232 with MAX1232CWE+ in the same package variant, and all timing and voltage specifications meet or exceed DS1232 requirements.