Analog Devices Inc./Maxim Integrated MAX6422XS26+

Overview

MAX6422XS26+ from Maxim Integrated is an active-high, push-pull microprocessor reset supervisor IC designed for precise VCC monitoring and configurable reset timeout in space-constrained systems. It monitors supply voltages from 1.6V to 5V with a factory-trimmed 2.625V reset threshold (±2.5% over temperature), delivers 1.6µA typical quiescent current, guarantees valid reset output down to VCC = 1V, and uses an external capacitor on the SRT pin to set timeout (e.g., 4.375ms with 1500pF). It is used in battery-powered controllers and portable medical instruments requiring reliable power-on reset with minimal current draw.

For engineers reviewing the MAX6422XS26+ datasheet, MAX6422XS26+ pinout, MAX6422XS26+ application, or MAX6422XS26+ equivalent, key selection criteria include its active-high push-pull output logic, SC70-4 package footprint, capacitor-adjustable timeout architecture, guaranteed operation at VCC ≥ 1V, and compatibility with low-voltage µP reset inputs requiring clean high-level assertion during power-up recovery.

Technical Context

The MAX6422XS26+ implements a precision voltage comparator with laser-trimmed resistors to detect VCC falling below 2.625V, triggering an immediate active-high RESET assertion. Its internal 240nA current source charges an external SRT capacitor to generate a programmable timeout delay after VCC recovers above threshold.

Unlike open-drain variants, the push-pull output drives high actively without external pull-up, simplifying interface to CMOS µP reset inputs. The device remains functional across –40°C to +125°C and maintains reset validity even as VCC drops to 1V - critical for brownout detection in wide-input industrial supplies.

Key Specifications

Pinout & Package

MAX6422XS26+ is housed in a 4-pin SC70-4 package (2.0mm × 1.25mm × 0.9mm), optimized for high-density PCB layouts in portable and wearable electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6421XS26+ and MAX6423XS26+, the MAX6422XS26+ uniquely provides active-high push-pull drive - reducing BOM count, eliminating pull-up resistor layout constraints, and simplifying integration with modern µPs that specify active-high reset assertion.

Availability

MAX6422XS26+ is available at Aetrix Electronics and suitable for battery-powered portable controllers, automotive body control modules, and wearable medical sensors requiring stable component supply, long-term lifecycle support, and lead-free compliance.

Supply support for MAX6422XS26+ 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 and mixed-signal ICs for power management, sensing, and interface applications in industrial, automotive, and medical markets.

The MAX6421–MAX6426 family delivers ultra-low-power, capacitor-programmable reset supervision for space- and energy-constrained embedded systems where deterministic power-on initialization is mission-critical.

FAQ

What is the exact reset threshold voltage of the MAX6422XS26+?

The MAX6422XS26+ features a factory-trimmed nominal reset threshold of 2.625V, with guaranteed accuracy of ±2.5% over the full operating temperature range (–40°C to +125°C). This value corresponds to the "26" suffix in the part number and is laser-trimmed during production to minimize external component dependency. The MAX6422XS26+ maintains this threshold stability without requiring calibration or external resistors.

How is the reset timeout period configured on the MAX6422XS26+?

The reset timeout period on the MAX6422XS26+ is set externally using a capacitor (CSRT) connected between the SRT pin and ground. The relationship is defined as tRP = (2.73 × 10⁶) × CSRT + 275µs, where tRP is in seconds and CSRT is in farads. For example, a 1500pF capacitor yields ~4.375ms timeout. Ceramic capacitors with leakage <10nA are recommended to ensure timing accuracy across temperature.

Does the MAX6422XS26+ support operation at VCC below 1.6V?

Yes - the MAX6422XS26+ is fully specified to operate down to VCC = 1.0V, and its RESET output remains valid (guaranteed VOH ≥ 0.8×VCC and VOL ≤ 0.4V) across this entire range. This capability enables reliable brownout detection in ultra-low-voltage systems such as energy-harvesting nodes or deeply discharged battery scenarios where other supervisors fail.

What package type does the MAX6422XS26+ use, and what are its dimensions?

The MAX6422XS26+ is packaged in a 4-pin SC70-4 (also labeled SC70) package measuring 2.0mm × 1.25mm × 0.9mm. This compact outline matches industry-standard footprints and supports high-density routing in portable and wearable PCBs. Pin 1 is SRT, pin 2 is GND, pin 3 is RESET, and pin 4 is VCC - consistent with SC70-4 JEDEC MO-203AB outlines.

Can the MAX6422XS26+ replace a MAX6421XS26+ without hardware changes?

No - the MAX6422XS26+ cannot directly replace the MAX6421XS26+ without board-level modification because it features an active-high RESET output versus the MAX6421XS26+'s active-low output. Swapping them would invert reset logic, causing the µP to remain held in reset or fail to initialize. A redesign is required to accommodate the polarity difference unless the host µP supports both active-high and active-low reset configurations.