Analog Devices Inc./Maxim Integrated MAX6326UR28-T

Overview

MAX6326UR28-T from Maxim Integrated is an ultra-low-power, active-low push-pull microprocessor supervisory circuit designed to monitor 2.8V supply rails in embedded systems. It asserts a reset signal when VCC falls below 2.800V (±1.5% at +25°C), holds reset for ≥100ms after VCC recovers, draws ≤1.0µA supply current at 3V, operates from 1.2V to 5.5V, and is housed in a 3-pin SOT23-3 package for portable power-sensitive applications.

For engineers reviewing the MAX6326UR28-T datasheet, MAX6326UR28-T pinout, MAX6326UR28-T application, or MAX6326UR28-T equivalent, this page delivers verified reset threshold accuracy, SOT23-3 terminal mapping, transient immunity specs, and validated alternatives for brownout detection in battery-powered µP systems.

Technical Context

The MAX6326UR28-T implements a precision bandgap-based voltage comparator with factory-trimmed 2.800V reset threshold, ±2.5% tolerance over –40°C to +85°C, and 40ppm/°C tempco. Its internal hysteresis is 6.3mV, ensuring noise immunity against VCC transients up to 200µs duration at 200mV overdrive.

It features a push-pull RESET output capable of sourcing 500µA at 0.8·VCC and sinking 1.6mA at ≤0.3V, guaranteed functional down to VCC = 1.2V, with no external components required and full specification across industrial temperature range.

Key Specifications

Pinout & Package

MAX6326UR28-T is supplied in a 3-pin SOT23-3 package with gull-wing leads, JEDEC MO-178AC compliant, RoHS-compliant, and rated for 320mW continuous power dissipation at +70°C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809TRD2-T and TPS3808G12QDBVRQ1, the MAX6326UR28-T delivers the lowest supply current, guaranteed operation down to 1.2V, and integrated push-pull output-making it optimal for long-life, low-voltage, and space-constrained µP supervision.

Availability

MAX6326UR28-T is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, and smart meter data loggers requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6326UR28-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, sensing, and interface applications, with emphasis on reliability and integration.

The MAX6326 family targets ultra-low-power microprocessor supervision in battery-operated and industrial systems, delivering factory-trimmed reset thresholds, minimal external dependencies, and robust transient immunity.

FAQ

What is the exact reset threshold voltage of MAX6326UR28-T and its tolerance?

The MAX6326UR28-T has a nominal reset threshold of 2.800V, with ±1.5% tolerance at +25°C and ±2.5% over the full –40°C to +85°C operating range. This value is factory-trimmed and specified in Table 1 of the datasheet; the "R28" suffix explicitly denotes the 2.800V variant. The device also features 6.3mV of internal hysteresis to prevent chatter near the threshold.

Does MAX6326UR28-T support operation below 1.8V, and what is its minimum functional VCC?

Yes, MAX6326UR28-T is guaranteed to operate correctly down to VCC = 1.2V across the full temperature range, enabling use in deep-sleep or energy-harvesting systems where supply voltage may fall well below standard logic levels. This capability is explicitly stated in the Electrical Characteristics table under "VCC Range" for –40°C to +85°C conditions.

What is the output configuration of MAX6326UR28-T, and how does it interface with common microcontrollers?

MAX6326UR28-T features an active-low push-pull RESET output, meaning it actively drives low during reset and actively drives high when released-no external pull-up resistor is needed. It interfaces directly with standard µP reset inputs such as those on ARM Cortex-M series, PIC, and AVR MCUs, simplifying design and reducing component count compared to open-drain alternatives.

How does MAX6326UR28-T handle power-supply transients, and what is its maximum tolerable glitch duration?

MAX6326UR28-T is designed to ignore fast negative-going VCC transients. According to the Typical Operating Characteristics graph "Maximum Transient Duration vs. Reset Threshold Overdrive", it rejects glitches up to 200µs in duration when the overdrive (VTH – VCC) is 200mV. This immunity prevents spurious resets in electrically noisy environments like motor control or switching power supply domains.

Is MAX6326UR28-T pin-compatible with legacy Maxim reset supervisors like MAX809?

Yes, MAX6326UR28-T is pin-compatible with MAX809-series devices in the SOT23-3 package, sharing identical pinout (VCC, RESET, GND) and footprint. However, differences exist in supply current (1.0µA vs. 1.6µA), low-VCC operation (1.2V vs. 1.8V min), and reset timeout consistency-so direct substitution requires validation of these parameters in the target application.