Analog Devices Inc./Maxim Integrated MAX6452UT29L-T

Overview

MAX6452UT29L-T from Maxim Integrated is a dual-supply microprocessor supervisor IC with one fixed-threshold (2.925V) and one adjustable-threshold (0.63V reference) voltage monitor, dual manual reset inputs (one extended-setup MR1, one immediate MR2), active-low open-drain RESET output, and 6.72s extended MR1 setup period. It ensures reliable system reset during power-up, brownout, and front-panel-initiated recovery in space-constrained consumer and industrial electronics.

For engineers reviewing the MAX6452UT29L-T datasheet, MAX6452UT29L-T pinout, MAX6452UT29L-T application, or MAX6452UT29L-T equivalent, key selection considerations include its 2.925V VCC threshold, 0.63V RSTIN reference for external divider-based monitoring, 6.72s MR1 hold time, immediate MR2 edge-triggered reset, and SOT23-6 open-drain output compatibility with mixed-voltage logic systems.

Technical Context

The MAX6452UT29L-T integrates two independent reset comparators: one monitors VCC against a factory-trimmed 2.925V threshold (±1.5% over -40°C to +85°C), while the other monitors RSTIN against a precision 0.630V internal reference (±0.015V, ±2.5mV hysteresis). Its dual manual reset architecture combines MR1 (active-low, 6.72s extended setup, internal 50kΩ pullup) and MR2 (active-high, immediate rising-edge triggered, 210ms debounced deassertion).

RESET assertion is one-shot: it pulses low for 140ms minimum (210ms typical) upon VCC/RSTIN undervoltage or valid MR1/MR2 activation. The open-drain output supports level-shifting up to 6V and guarantees valid logic down to VCC = 1.0V, with VOL ≤ 0.4V at 3.2mA sink current.

Key Specifications

Pinout & Package

MAX6452UT29L-T is housed in a RoHS-compliant 6-pin SOT23 package (U6-1 outline, 90-0175 land pattern), measuring 2.9mm × 1.6mm × 1.1mm, suitable for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6452UT29L-T, MAX6451UT29L-T offers identical supervision functionality but eliminates the need for a pullup resistor at the expense of bus-sharing flexibility, while TPS3808G33DBVR reduces feature count and quiescent current but cannot replace the dual-rail, dual-reset capability required in complex embedded systems.

Availability

MAX6452UT29L-T is available at Aetrix Electronics and suitable for set-top box manufacturing, smart card reader design, DVD player development, industrial modem production, and medical device qualification requiring stable component supply across extended temperature ranges.

Supply support for MAX6452UT29L-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 for demanding environments.

The MAX6443–MAX6452 family was engineered specifically for robust microprocessor supervision in consumer, industrial, and automotive systems where immunity to switch bounce, voltage transients, and multi-rail dependencies is critical.

FAQ

What is the exact VCC reset threshold voltage for MAX6452UT29L-T?

The MAX6452UT29L-T has a factory-trimmed VCC reset threshold of 2.925V, with guaranteed tolerance of ±1.5% over the full -40°C to +85°C operating temperature range. This value is confirmed in Table 1 of the datasheet, where the "29" suffix corresponds to the 2.925V nominal threshold, and electrical characteristics specify min/typ/max values of 2.85V/2.925V/3.00V.

How does the MR2 pin function on MAX6452UT29L-T?

On the MAX6452UT29L-T, MR2 is an active-high, immediate manual reset input. A rising edge on MR2 triggers a one-shot RESET pulse (140ms min) without any hold-time requirement. The pin is internally debounced for 210ms on the falling edge to prevent false resets during card removal, and its 100ns glitch rejection ensures noise immunity in noisy environments.

Can MAX6452UT29L-T monitor a 1.2V supply rail?

Yes, the MAX6452UT29L-T can monitor a 1.2V supply using its RSTIN pin. With the internal 0.630V reference, a resistor divider (e.g., R1 = 909kΩ, R2 = 1MΩ) sets the trip point to 1.2V per the formula VMON-TH = 0.63 × (R1 + R2)/R2. The RSTIN input draws only ±25nA, enabling high-impedance dividers that minimize power loss.

What is the purpose of the 6.72s MR1 setup period on MAX6452UT29L-T?

The 6.72s MR1 setup period on MAX6452UT29L-T prevents accidental system resets caused by brief button presses during normal operation. It requires MR1 to remain low for the full duration before asserting RESET, ensuring that only intentional, sustained user actions (e.g., holding a front-panel reset button for >6 seconds) initiate recovery-critical for preventing data loss in consumer electronics.

Does MAX6452UT29L-T support operation below 1.0V VCC?

No, the MAX6452UT29L-T is not specified to operate below VCC = 1.0V. Its absolute minimum operating voltage is 1.0V, and RESET output validity (VOL ≤ 0.4V) is guaranteed only down to this level. For applications requiring reset assertion at VCC < 1.0V, an external pulldown resistor is needed-but only with push-pull variants, not the open-drain MAX6452UT29L-T.