Analog Devices Inc./Maxim Integrated MAX6327XR25-T

Overview

MAX6327XR25-T from Maxim Integrated is an active-high push-pull microprocessor supervisory circuit designed to monitor 2.5V power supplies and assert a reset signal during brownout or power-up conditions. It features a factory-trimmed 2.500V reset threshold (±1.5% at +25°C, ±2.5% over -40°C to +85°C), 100ms minimum reset timeout, ultra-low 1µA max supply current, and operates down to 1.2V VCC. It is used in portable battery-powered equipment requiring reliable, low-power power-on reset functionality.

For engineers reviewing the MAX6327XR25-T datasheet, MAX6327XR25-T pinout, MAX6327XR25-T application, or MAX6327XR25-T equivalent, key selection criteria include its active-high push-pull RESET output, SC70-3 package, 2.5V threshold accuracy over temperature, transient immunity, and compatibility with µP systems requiring guaranteed reset assertion below VCC = 1.2V.

Technical Context

The MAX6327XR25-T implements a precision bandgap-based voltage comparator with hysteresis (6.3mV) to detect VCC falling below 2.500V and hold RESET high for ≥100ms after recovery. Its internal circuitry guarantees correct reset state down to VCC = 1.2V and rejects fast transients via built-in noise immunity design.

It uses a single-supply architecture with no external components required, delivering deterministic reset timing across -40°C to +85°C. The push-pull output drives high (VOH ≥ 0.8·VCC at ISOURCE = 500µA) when asserted and low (VOL ≤ 0.4V at ISINK = 3.2mA) when deasserted, enabling direct interface with µP reset inputs without pull-up resistors.

Key Specifications

Pinout & Package

MAX6327XR25-T is housed in a 3-pin SC70-3 package (outline X3-2), footprint-compatible with SOT23-3 but with smaller dimensions (2.0mm × 2.1mm × 0.9mm). This space-saving package supports high-density PCB layouts in portable electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6327UR25-T, the MAX6327XR25-T saves PCB area with SC70-3 while maintaining identical performance; versus TPS3125M25DBVR, it delivers guaranteed 100ms reset without external components-critical for cost-sensitive, high-volume portable designs.

Availability

MAX6327XR25-T is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, and smart meter communication units requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6327XR25-T 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 industrial, computing, and consumer applications.

The MAX6326/MAX6327/MAX6328 family targets ultra-low-power microprocessor supervision in battery-critical systems, emphasizing minimal ICC, guaranteed low-VCC operation, and factory-trimmed voltage thresholds for plug-and-play reliability.

FAQ

What is the exact reset threshold voltage of the MAX6327XR25-T and how tightly is it specified?

The MAX6327XR25-T has a nominal reset threshold of 2.500V, factory-trimmed to ±1.5% at +25°C and ±2.5% over the full -40°C to +85°C operating range. This specification ensures precise detection of 2.5V supply faults without external calibration. The MAX6327XR25-T achieves this accuracy using laser-trimmed internal resistors and is validated per Maxim's production test flow.

Does the MAX6327XR25-T require any external components to function?

No, the MAX6327XR25-T requires zero external components. Its internal precision voltage reference, comparator, and push-pull output driver are fully integrated. Unlike some supervisors needing external capacitors for timeout adjustment, the MAX6327XR25-T provides a fixed 100ms minimum reset pulse width inherently-making it ideal for simplified, high-reliability designs where BOM reduction is critical.

What is the lowest VCC voltage at which the MAX6327XR25-T guarantees correct reset behavior?

The MAX6327XR25-T guarantees correct reset state (i.e., RESET remains high while VCC is below threshold and for ≥100ms after crossing it) down to VCC = 1.2V over the full -40°C to +85°C temperature range. This is explicitly specified in the Electrical Characteristics table and verified across process corners. Below 1.2V, behavior is not guaranteed-so the MAX6327XR25-T supports robust operation during deep brownout scenarios common in battery-powered systems.

How does the MAX6327XR25-T handle fast transients on the VCC supply line?

The MAX6327XR25-T incorporates transient immunity circuitry that ignores fast negative-going VCC glitches. Per the Typical Operating Characteristics graph "Maximum Transient Duration vs. Reset Threshold Overdrive", it tolerates a 200mV overdrive glitch for up to ~100µs without issuing a false reset. This design prevents spurious resets caused by switching noise or coupling-ensuring system stability in electrically noisy environments where the MAX6327XR25-T is deployed.

Is the MAX6327XR25-T pin-compatible with older Maxim reset ICs like the MAX809?

Yes, the MAX6327XR25-T is pin-compatible with the MAX809 series in SC70-3 package. Both share identical 3-pin SC70 pinout (VCC, RESET, GND), same active-high push-pull output behavior, and overlapping supply ranges. However, the MAX6327XR25-T improves upon the MAX809 with lower ICC (1µA vs. 12µA), tighter threshold tolerance (±1.5% vs. ±2.5%), and guaranteed operation down to 1.2V (vs. 1.0V for MAX809, but with less margin). Designers can directly substitute MAX6327XR25-T for MAX809 in existing SC70 layouts.