Analog Devices Inc./Maxim Integrated MAX6456UT31L+T

Overview

MAX6456UT31L+T from Maxim Integrated is a dual-voltage microprocessor supervisor IC with separate active-low open-drain VCC reset and manual reset outputs, factory-set 3.075V VCC threshold, 1.68s extended MR setup period (L suffix), 140ms min reset timeout, and adjustable RSTIN input supporting down to 0.63V. It enables soft/hard system reset combination in embedded power management for consumer electronics and industrial equipment.

For engineers reviewing the MAX6456UT31L+T datasheet, MAX6456UT31L+T pinout, MAX6456UT31L+T application, or MAX6456UT31L+T equivalent, key selection criteria include its dual-output reset architecture, open-drain output compatibility with mixed-voltage systems, guaranteed valid reset down to VCC = 1.0V, and precise 3.075V factory-trimmed threshold with ±1.5% accuracy over temperature.

Technical Context

The MAX6456UT31L+T implements a dual-comparator supervision architecture: one precision bandgap-based comparator monitors VCC against a fixed 3.075V threshold, while a high-impedance comparator monitors RSTIN against a fixed 0.63V reference, enabling external resistor-divider configuration for secondary voltage monitoring. Its MR input controls both MROUT and RESET outputs via an extended setup timeout mechanism.

This device uses BiCMOS process technology to achieve 6µA typical supply current at 3.6V, supports operation from 1.0V to 5.5V VCC, and guarantees reset assertion validity even as VCC decays to 1.0V - critical for brownout detection in low-power embedded systems requiring deterministic startup and recovery behavior.

Key Specifications

Pinout & Package

MAX6456UT31L+T is housed in a lead(Pb)-free SOT23-6 package (U6-1 land pattern), measuring 2.9mm × 1.6mm × 1.1mm, with gull-wing leads and RoHS-compliant finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6455UT31L+T, the MAX6456UT31L+T provides open-drain flexibility for multi-drop reset buses and mixed-voltage interfacing, while TPS3808G33DBVR offers lower current and simpler integration at the expense of supervision versatility and dual-output control.

Availability

MAX6456UT31L+T is available at Aetrix Electronics and suitable for set-top boxes, cable/DSL modems, and industrial equipment requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6456UT31L+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 is a semiconductor company specializing in analog and mixed-signal ICs for power management, interface, sensing, and communication applications.

The MAX6453–MAX6456 family was designed specifically for dual-rail microprocessor supervision in space-constrained consumer and industrial systems, emphasizing low power, precision thresholding, and flexible reset control architecture.

FAQ

What is the exact VCC reset threshold voltage for MAX6456UT31L+T?

The MAX6456UT31L+T has a factory-set VCC reset threshold of 3.075V, with ±1.5% tolerance over the full -40°C to +85°C operating temperature range. This value is laser-trimmed during production and specified in Table 1 of the datasheet under the "31" suffix code. The threshold remains stable with 60ppm/°C tempco, ensuring reliable brownout detection across environmental conditions.

How does the MR input control both RESET and MROUT in MAX6456UT31L+T?

In MAX6456UT31L+T, the MR input controls both outputs via an extended setup timeout: pulling MR low for less than 6.72s (typical L-suffix period) asserts only MROUT, while holding MR low for ≥6.72s asserts both MROUT and RESET. After MR release, both outputs remain low for 140ms minimum before deasserting. This enables single-button interrupt-before-reset functionality without external timing circuitry.

Can MAX6456UT31L+T monitor a 1.2V supply using the RSTIN pin?

Yes, MAX6456UT31L+T can monitor a 1.2V supply using RSTIN by connecting it to the center node of an external resistor divider referenced to that supply. With RSTIN's fixed 0.63V threshold, a 1.2V rail requires R1/R2 ≈ 0.905 (e.g., R2 = 250kΩ, R1 = 226kΩ). The high-impedance RSTIN input draws only ±25nA, minimizing divider current and power loss.

What is the minimum VCC voltage at which MAX6456UT31L+T guarantees valid RESET output logic?

MAX6456UT31L+T guarantees valid RESET output logic down to VCC = 1.0V. Below this, current-sinking capability degrades and output state becomes indeterminate. This specification ensures reliable reset assertion during deep brownout events common in battery-powered or unregulated supply systems, unlike many supervisors that require ≥1.8V for functional reset behavior.

Is MAX6456UT31L+T compatible with 5V logic systems despite its 3.3V VCC threshold?

Yes, MAX6456UT31L+T supports VCC up to 5.5V and its open-drain RESET and MROUT outputs can interface with 5V logic via external pullup to 5V - even when VCC = 3.3V. The datasheet confirms absolute maximum ratings allow 6V on open-drain pins, and leakage current remains ≤1µA when deasserted, making it suitable for mixed-voltage system reset buses.