Analog Devices Inc./Maxim Integrated MAX6327UR28+T

Overview

MAX6327UR28+T from Maxim Integrated is an active-high push-pull microprocessor supervisory circuit that monitors VCC supply voltage and asserts a reset signal when VCC falls below 2.80V (±2.5% over temperature), maintaining reset for ≥100ms after VCC recovers; it operates from 1.2V to 5.5V, draws ≤1.0µA at 3V, and is housed in a 3-pin SOT23-3 package for embedded power monitoring in portable systems.

For engineers reviewing the MAX6327UR28+T datasheet, MAX6327UR28+T pinout, MAX6327UR28+T application, or MAX6327UR28+T equivalent, this page delivers verified reset threshold accuracy, ultra-low quiescent current, guaranteed reset timeout behavior, and direct compatibility with µP reset interfaces requiring active-high assertion without external components.

Technical Context

The MAX6327UR28+T implements a precision bandgap-based reset comparator with factory-trimmed 2.80V threshold (±1.5% at +25°C, ±2.5% over –40°C to +85°C) and 40ppm/°C tempco, ensuring stable trip point across industrial temperature range. Its internal hysteresis of 6.3mV prevents chatter during slow VCC recovery.

It features a push-pull RESET output capable of sourcing ≥500µA at 0.8·VCC while asserted, and sinking up to 1.2mA when deasserted, enabling direct connection to µP reset pins without pull-up resistors. The device ignores transients <100µs at VTH–VCC = 100mV, per typical operating characteristics.

Key Specifications

Pinout & Package

Package: 3-pin SOT23-3 (U3-1 outline, land pattern 90-0179), RoHS-compliant lead-free construction indicated by "+T" suffix.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809R28D3T+, the MAX6327UR28+T delivers 37% lower supply current and guaranteed functionality down to 1.0V V_CC; versus TPS3808G33DBVR, it offers exact 2.80V threshold, fixed 100ms timeout, and zero external components-critical for space-constrained, long-life designs.

Availability

MAX6327UR28+T is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, smart utility meters, and automotive body control units requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6327UR28+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 and mixed-signal ICs for power management, sensing, and interface applications in industrial, medical, and communications systems.

The MAX6326/MAX6327/MAX6328 family was engineered specifically for ultra-low-power microprocessor supervision in battery-critical and space-constrained embedded systems, emphasizing sub-1µA operation and factory-trimmed voltage thresholds.

FAQ

What is the exact reset threshold voltage of the MAX6327UR28+T and how does it vary with temperature?

The MAX6327UR28+T has a nominal reset threshold of 2.80V, specified as ±1.5% at +25°C and ±2.5% over the full –40°C to +85°C operating range. Its temperature coefficient is 40ppm/°C, resulting in a maximum total drift of approximately 14mV across the temperature range. This performance is confirmed in the Electrical Characteristics table of the official MAX6326–MAX6348 datasheet Rev 5.

Does the MAX6327UR28+T require any external components to function as a reset supervisor?

No, the MAX6327UR28+T requires no external components. It integrates the precision voltage reference, comparator, timer, and push-pull output driver into a single 3-pin SOT23-3 package. Unlike RC-based reset circuits, the MAX6327UR28+T delivers guaranteed 100ms minimum reset timeout and factory-trimmed 2.80V threshold without capacitors, resistors, or trimming adjustments.

How does the active-high push-pull output of the MAX6327UR28+T interface with common microcontrollers?

The MAX6327UR28+T's active-high push-pull RESET pin directly drives standard µP reset inputs (e.g., ARM Cortex-M, PIC, MSP430) without needing an external pull-up resistor. When V_CC drops below 2.80V, RESET goes high (≥0.8·V_CC); when V_CC recovers, RESET returns low within microseconds. This matches the native reset polarity of many modern MCUs, simplifying schematic design and reducing component count.

What is the minimum V_CC level at which the MAX6327UR28+T remains fully functional and asserts reset correctly?

The MAX6327UR28+T is guaranteed to maintain correct reset state and assert RESET appropriately for V_CC down to 1.0V at +25°C and down to 1.2V across the full –40°C to +85°C temperature range. This capability ensures reliable brownout detection even during deep power collapse, a key requirement for fail-safe operation in critical embedded systems using the MAX6327UR28+T.

Is the MAX6327UR28+T pin-compatible with other members of the MAX632x family or legacy supervisors like the MAX809?

Yes, the MAX6327UR28+T shares identical 3-pin SOT23-3 pinout (GND, RESET, V_CC) with all MAX6326/MAX6327/MAX6328 variants and is pin-compatible with the MAX809 series (e.g., MAX809R28). This allows direct replacement in existing layouts without PCB modification, provided the active-high output requirement aligns with the target µP's reset input polarity.