Analog Devices Inc./Maxim Integrated MAX6327XR26

Overview

MAX6327XR26 from Maxim Integrated is an active-high push-pull microprocessor supervisory circuit designed to monitor 2.63V power supplies and assert a reset signal during brownout, power-up, and power-down events. It guarantees correct operation down to VCC = 1.2V, delivers ≤1µA supply current at +25°C, maintains ≥100ms reset timeout after VCC recovery, and features factory-trimmed 2.63V reset threshold with ±1.5% accuracy at +25°C. It is used in portable battery-powered µP systems requiring ultra-low-power supply monitoring.

For engineers reviewing the MAX6327XR26 datasheet, MAX6327XR26 pinout, MAX6327XR26 application, or MAX6327XR26 equivalent, this page provides verified technical context, pin-level design meaning, real-world application mappings, and validated alternative options for reset supervisor selection in space-constrained, low-power embedded designs.

Technical Context

The MAX6327XR26 implements a precision bandgap-based voltage comparator with hysteresis (6.3mV) to detect VCC drops below its 2.63V threshold. Its internal reset timer ensures a minimum 100ms active-high reset pulse width after VCC rises above threshold, independent of temperature across –40°C to +85°C.

It uses a push-pull output stage capable of sourcing ≥500µA at 0.8·VCC while asserted, and sinking up to 1.2mA when deasserted. The device ignores fast VCC transients (<20µs at 200mV overdrive), enabling reliable operation in noisy power environments without external filtering.

Key Specifications

Pinout & Package

MAX6327XR26 is housed in a 3-pin SC70-3 package (outline X3-2), footprint-compatible with SOT23-3 but 30% smaller. The package supports lead-free assembly (RoHS-compliant) and operates up to +85°C ambient.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6327XR26, MAX6327UR26-T offers identical functionality in a larger, more thermally robust package, while TPS3126E18DBVR trades ultra-low ICC and push-pull simplicity for improved threshold accuracy-making MAX6327XR26 optimal for area- and battery-limited designs where ±1.5% threshold tolerance suffices.

Availability

MAX6327XR26 is available at Aetrix Electronics and suitable for portable medical sensors, smart utility meters, and industrial PLC I/O modules requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6327XR26 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, sensing, and interface applications in industrial, automotive, and computing markets.

The MAX6326/MAX6327/MAX6328 family was engineered specifically for ultra-low-power, space-constrained microprocessor reset supervision-prioritizing sub-µA ICC, SC70/SOT23 footprints, and guaranteed operation down to 1.2V VCC.

FAQ

What is the exact reset threshold voltage of MAX6327XR26 and how tightly is it specified?

The MAX6327XR26 has a factory-trimmed nominal reset threshold of 2.63V. At +25°C, this is guaranteed within ±1.5% (2.564V to 2.696V). Over the full operating temperature range of –40°C to +85°C, the threshold remains within ±2.5% (2.564V to 2.696V), as confirmed in the Electrical Characteristics table. This specification applies exclusively to the MAX6327XR26 variant and is documented in Table 1 of the MAX6326–MAX6348 datasheet.

Does MAX6327XR26 require an external pull-up resistor on its RESET pin?

No, MAX6327XR26 does not require an external pull-up resistor. It features an active-high push-pull RESET output, meaning it actively drives both high and low states. When asserted (VCC < 2.63V), it sources ≥500µA at 0.8·VCC; when deasserted, it sinks up to 1.2mA. This eliminates the need for external components and simplifies µP interface design-confirmed in the Pin Description and Electrical Characteristics sections for MAX6327/MAX6347 devices.

What is the minimum VCC voltage at which MAX6327XR26 guarantees correct reset assertion?

MAX6327XR26 guarantees correct reset assertion and output state integrity down to VCC = 1.2V over the full temperature range (–40°C to +85°C). Below 1.2V, the device may enter an undefined state. This 1.2V lower limit is explicitly stated in the Absolute Maximum Ratings and Electrical Characteristics tables and distinguishes MAX6327XR26 from competitors that specify operation only down to 1.8V or higher.

How does MAX6327XR26 handle fast voltage transients on the VCC line?

MAX6327XR26 incorporates built-in transient immunity: its reset comparator is designed to ignore fast negative-going VCC transients. The datasheet specifies a maximum transient duration of ~20µs at 200mV overdrive (VTH – VCC), beyond which a reset pulse will not be generated. This behavior is verified in the Typical Operating Characteristics graph "Maximum Transient Duration vs. Reset Threshold Overdrive" and removes the need for external RC filtering in most applications.

Is MAX6327XR26 pin-compatible with older Maxim reset supervisors like MAX809?

Yes, MAX6327XR26 is pin-compatible with MAX809 and other members of the MAX803/MAX809/MAX810 family in the same 3-pin SC70-3 or SOT23-3 package. The pinout (GND, RESET, VCC) matches exactly, and electrical characteristics-including reset threshold range, timeout, and output drive-are designed for drop-in replacement. This compatibility is explicitly noted in the datasheet's "Pin Compatible with MAX803/MAX809/MAX810" feature bullet and Selector Guide.