Analog Devices Inc./Maxim Integrated MAX6327XR22-T

Overview

MAX6327XR22-T from Maxim Integrated is an active-high push-pull microprocessor supervisory circuit designed to monitor VCC supply voltage and assert a reset signal during power-up, power-down, or brownout conditions. It features a factory-trimmed 2.20V 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 guaranteed operation down to 1.2V VCC. It is used in portable battery-powered systems requiring reliable, low-power reset supervision.

For engineers reviewing the MAX6327XR22-T datasheet, MAX6327XR22-T pinout, MAX6327XR22-T application, or MAX6327XR22-T equivalent, key selection criteria include reset threshold accuracy, active-high push-pull output drive capability, SC70-3 package footprint, temperature-stable hysteresis (6.3mV), and immunity to fast VCC transients up to 100V/µs slew rate.

Technical Context

The MAX6327XR22-T implements a precision bandgap-based reset comparator with internal hysteresis (6.3mV) and a dedicated power-on reset timer. Its active-high push-pull RESET output drives high (≥0.8·VCC at 500µA) when VCC is below 2.20V or during the 100–280ms timeout after VCC rises above threshold, and drives low (≤0.4V at 1.2mA) otherwise.

It operates across the full industrial temperature range (–40°C to +85°C) with supply current stable from 0.5µA to 1.0µA (typical at 3V), and supports VCC from 1.2V to 5.5V. The device ignores negative-going VCC transients shorter than ~100µs at 200mV overdrive, per its transient immunity specification.

Key Specifications

Pinout & Package

MAX6327XR22-T is housed in a 3-pin SC70-3 package (outline X3-2, land pattern 90-0208), measuring 2.0mm × 2.1mm × 0.95mm, with gull-wing leads and RoHS-compliant lead-free finish (marked "AAI" on top).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809TR22-T and TPS3808G12DBVR, MAX6327XR22-T uniquely delivers 1µA max ICC, guaranteed 1.2V operation, and SC70-3 pinout - making it optimal for ultra-low-power, space-constrained, and deep-brownout-critical applications where minimal bill-of-materials and proven reliability are mandatory.

Availability

MAX6327XR22-T is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, battery-powered smart meters, and automotive body control units requiring stable component supply, long-lifecycle support, and consistent parametric performance across production batches.

Supply support for MAX6327XR22-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) is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, communications, and consumer markets.

The MAX6326/MAX6327/MAX6328 family was designed specifically for ultra-low-power microprocessor reset supervision in battery-operated and space-constrained systems, emphasizing precision threshold accuracy, minimal quiescent current, and robust transient immunity.

FAQ

What is the exact reset threshold voltage of MAX6327XR22-T and how does it vary with temperature?

The MAX6327XR22-T has a factory-trimmed nominal reset threshold of 2.20V. At +25°C, this is guaranteed within ±1.5% (2.167V to 2.233V). Over the full operating temperature range of –40°C to +85°C, the threshold remains within ±2.5% (2.145V to 2.250V). This tight tolerance ensures reliable brownout detection without external calibration, and the 40ppm/°C tempco minimizes drift across thermal gradients in deployed systems. The MAX6327XR22-T maintains this specification while drawing only 1µA max supply current.

Does MAX6327XR22-T support active-high reset output, and what are its drive capabilities?

Yes, the MAX6327XR22-T provides an active-high push-pull RESET output - a key differentiator from open-drain or active-low variants in the same family. When asserted (VCC < 2.20V or during timeout), it sources ≥0.8·VCC at 500µA (e.g., ≥2.4V at VCC = 3.0V). When deasserted, it sinks ≤0.4V at 1.2mA (VCC ≥ 3.2V). This eliminates the need for an external pull-up resistor and allows direct interfacing with µP RESET pins expecting active-high logic, such as many ARM Cortex-M and Renesas RX series MCUs. The MAX6327XR22-T's push-pull architecture ensures clean, fast edges without RC delays.

What package type and footprint does MAX6327XR22-T use, and is it compatible with common alternatives?

The MAX6327XR22-T uses the 3-pin SC70-3 package (outline X3-2, land pattern 90-0208), measuring 2.0mm × 2.1mm × 0.95mm. It is pin-compatible with the MAX809/MAX810 in SC70-3 and shares identical pad geometry with the SOT23-3 variant (MAX6327UR22-T), enabling layout reuse across both packages. Its top-marking "AAI" confirms the 2.20V threshold and SC70-3 variant. Unlike larger SOIC or TSSOP supervisors, the MAX6327XR22-T's SC70-3 footprint saves >60% board area - critical for wearables and implantables. The MAX6327XR22-T is not compatible with 5-pin or 8-pin reset ICs due to its minimal 3-pin interface.

How does MAX6327XR22-T handle fast voltage transients on the VCC line?

The MAX6327XR22-T incorporates proprietary comparator design and internal filtering to reject fast negative-going VCC transients. Per its Typical Operating Characteristics, it ignores glitches shorter than ~100µs when the overdrive (VTH – VCC) is 200mV, and tolerates progressively shorter pulses as overdrive increases - e.g., <20µs at 1V overdrive. This immunity is validated up to 100V/µs slew rate, making the MAX6327XR22-T robust against switching regulator noise, relay bounce, and ESD-induced supply dips. Unlike basic reset ICs, the MAX6327XR22-T's transient rejection is specified and tested, preventing false resets in electrically harsh environments like factory automation or automotive subsystems.

What is the minimum VCC voltage at which MAX6327XR22-T guarantees correct reset assertion and release behavior?

The MAX6327XR22-T guarantees correct functional behavior - including valid reset assertion when VCC falls below 2.20V and proper release after timeout - down to VCC = 1.2V across the full –40°C to +85°C temperature range. This is explicitly stated in the Electrical Characteristics table and distinguishes it from many competing supervisors that require ≥1.8V or ≥2.0V minimum VCC. The ability to operate at 1.2V enables reliable reset generation during deep battery discharge (e.g., Li-SOCl₂ cells dropping to 2.0V open-circuit, yielding ~1.3V under load) and supports next-generation ultra-low-voltage MCUs. The MAX6327XR22-T maintains its 1µA max ICC and 2.20V threshold accuracy even at this minimum VCC.