Analog Devices Inc./Maxim Integrated MAX6326UR22+T

Overview

MAX6326UR22+T from Maxim Integrated is an ultra-low-power, active-low push-pull microprocessor supervisory circuit designed to monitor 2.5V–5V power supplies and assert a reset signal during brownout or power-up/down events. It features a factory-trimmed 2.20V reset threshold (±2.5% over -40°C to +85°C), 100ms minimum reset timeout, 1µA max supply current at 3V, and operates down to 1.2V VCC. It is used in portable battery-powered systems requiring reliable, low-quiescent-power reset assertion.

For engineers reviewing the MAX6326UR22+T datasheet, MAX6326UR22+T pinout, MAX6326UR22+T application, or MAX6326UR22+T equivalent, key selection criteria include its 2.20V threshold accuracy, SOT23-3 package compatibility, push-pull active-low RESET output, and guaranteed operation down to 1.2V - critical for low-voltage embedded and portable designs.

Technical Context

The MAX6326UR22+T implements a precision bandgap-based voltage comparator with hysteresis (6.3mV) to detect VCC drops below its 2.20V threshold and maintain RESET assertion for ≥100ms after recovery. Its internal circuitry ignores fast transients (<20µs at 200mV overdrive), ensuring immunity to power-supply noise.

It uses a single-stage push-pull output stage capable of sourcing 500µA at 0.8·VCC and sinking 1.6mA at ≤0.3V, eliminating external pull-up components. The device is fully specified across -40°C to +85°C and requires no external capacitors or resistors.

Key Specifications

Pinout & Package

MAX6326UR22+T is housed in a 3-pin SOT23-3 package (outline 21-0051), with 0.95mm pitch, 2.92mm × 1.3mm footprint, and thermal pad omitted. Pin 1 = GND, Pin 2 = RESET (active-low push-pull), Pin 3 = VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809TRD2+T and TPS3808G01DBVR, the MAX6326UR22+T delivers superior battery life (1µA vs. ≥1.8µA), tighter threshold accuracy (±2.5% vs. ±3.5%), and guaranteed 100ms fixed timeout without external components - making it optimal for space-constrained, long-life portable designs.

Availability

MAX6326UR22+T is available at Aetrix Electronics and suitable for battery-powered IoT sensors, industrial PLC modules, and medical wearables requiring stable component supply, RoHS-compliant packaging, and tape-and-reel delivery for automated assembly.

Supply support for MAX6326UR22+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, medical, communications, and consumer applications.

The MAX6326 family delivers ultra-low-power, factory-trimmed supervisory circuits targeting portable, battery-critical, and space-constrained embedded systems requiring deterministic reset behavior without external components.

FAQ

What is the exact reset threshold voltage of MAX6326UR22+T and how stable is it over temperature?

The MAX6326UR22+T has a nominal reset threshold of 2.20V, with a guaranteed tolerance of ±2.5% over the full operating temperature range (-40°C to +85°C). At +25°C, the threshold is 2.200V ±1.5%. This precision is achieved via factory laser trimming and is supported by a low 40ppm/°C tempco, ensuring minimal drift across environmental conditions. The MAX6326UR22+T maintains this specification without requiring external calibration.

Does MAX6326UR22+T require any external components to function as a reset supervisor?

No, the MAX6326UR22+T operates autonomously with no external components required. Its internal precision voltage reference, comparator, and push-pull output stage eliminate the need for external resistors, capacitors, or pull-up networks. This simplifies layout, reduces BOM count, and improves reliability compared to discrete reset solutions - a key design advantage confirmed in the MAX6326UR22+T datasheet.

What is the maximum allowable negative-going VCC transient that will not trigger a false reset on MAX6326UR22+T?

The MAX6326UR22+T rejects negative-going VCC transients up to 20µs in duration when the overdrive (VTH – VCC) is 200mV, as shown in the Typical Operating Characteristics graph "Maximum Transient Duration vs. Reset Threshold Overdrive". For smaller overdrives (e.g., 20mV), the allowable pulse width increases to ~140µs. This built-in transient immunity prevents spurious resets caused by power-rail noise or switching spikes.

Can MAX6326UR22+T drive a standard CMOS RESET input directly without a pull-up resistor?

Yes, the MAX6326UR22+T features a push-pull RESET output capable of both sourcing and sinking current. It can directly drive standard CMOS RESET inputs without an external pull-up resistor: it sources up to 500µA at 0.8·VCC when high and sinks up to 1.6mA at ≤0.3V when low. This eliminates component count and layout complexity - a verified capability documented in the MAX6326UR22+T electrical characteristics table.

Is MAX6326UR22+T compatible with 1.8V or 2.8V supply rails?

Yes, the MAX6326UR22+T operates over a VCC range of 1.2V to 5.5V and is fully specified down to 1.2V. It reliably monitors 1.8V and 2.8V rails - for example, asserting reset when a 2.8V LDO output sags below 2.20V. Its ability to function at 1.2V ensures supervision remains active even during deep brownout conditions where other supervisors may fail, a feature explicitly guaranteed in the MAX6326UR22+T datasheet.