Analog Devices Inc./Maxim Integrated MAX6456UT46S+T

Overview

MAX6456UT46S+T from Maxim Integrated is a dual-voltage microprocessor supervisor IC with separate active-low open-drain VCC reset and manual reset outputs, 4.625V factory-set VCC threshold, 0.63V adjustable RSTIN threshold, 140ms minimum reset timeout, and 3.36s extended MR setup period for soft/hard reset combination. It operates from 1.0V to 5.5V supply and supports brownout detection in consumer electronics power management.

For engineers reviewing the MAX6456UT46S+T datasheet, MAX6456UT46S+T pinout, MAX6456UT46S+T application, or MAX6456UT46S+T equivalent, key selection criteria include its dual-output reset architecture, open-drain output compatibility with mixed-voltage systems, guaranteed reset validity down to VCC = 1.0V, and integrated transient immunity for reliable operation in noisy environments.

Technical Context

The MAX6456UT46S+T implements a dual-comparator architecture: one precision bandgap reference comparator monitors VCC against a fixed 4.625V threshold, while a second high-impedance comparator monitors RSTIN against a fixed 0.63V reference-enabling external resistor-divider configuration for secondary voltage monitoring down to 0.63V. Its BiCMOS process ensures low leakage and stable hysteresis.

Unlike the MAX6453/MAX6454, the MAX6456UT46S+T uses a single MR input to control both MROUT and RESET outputs: MR assertion for <3.36s triggers only MROUT (soft interrupt), while MR held ≥3.36s asserts both MROUT and RESET (hard reboot). Both outputs are open-drain, requiring external pullups and supporting level-shifting across 0–6V logic domains.

Key Specifications

Pinout & Package

Supplied in a RoHS-compliant lead(Pb)-free SOT23-6 package (U6-1 land pattern), footprint-compatible with standard 6-pin SOT23 footprints and rated for -40°C to +85°C operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6455UT46S+T, the MAX6456UT46S+T's open-drain outputs provide flexible interfacing across voltage domains but require external pullups; compared with TPS3808G33DBVR, it delivers differentiated reset control and dual-rail supervision essential for complex embedded recovery protocols.

Availability

MAX6456UT46S+T is available at Aetrix Electronics and suitable for set-top boxes, cable modems, DVD players, and medical devices requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6456UT46S+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 management, sensing, and connectivity in industrial, automotive, and consumer systems.

The MAX6453–MAX6456 family targets cost-sensitive, space-constrained embedded systems needing robust dual-rail supervision and user-initiated recovery-especially where a single pushbutton must serve both interrupt and reboot roles.

FAQ

What is the exact VCC reset threshold voltage for MAX6456UT46S+T?

The MAX6456UT46S+T has a factory-set VCC reset threshold of 4.625V, with a guaranteed range of 4.50V to 4.75V across temperature (-40°C to +85°C). This value is fixed by the "46" suffix in the part number per Table 1 of the datasheet and applies specifically to the MAX6456UT46S+T-not derived from generic family data. The threshold exhibits 60ppm/°C tempco and includes built-in hysteresis of approximately 2×VTH mV.

How does the manual reset input (MR) function differently on MAX6456UT46S+T versus MAX6454UT46S+T?

On the MAX6456UT46S+T, the MR input controls both MROUT and RESET outputs: short MR pulses (<3.36s) assert only MROUT (soft interrupt), while long pulses (≥3.36s) assert both outputs (hard reset). In contrast, MAX6454UT46S+T's MR affects only MROUT; its RESET output responds solely to VCC/RSTIN faults. This difference stems from distinct internal logic architectures confirmed in the Pin Description and Functional Diagram sections of the MAX6453–MAX6456 datasheet.

Can MAX6456UT46S+T monitor a 1.8V supply using the RSTIN pin?

Yes, the MAX6456UT46S+T can monitor a 1.8V supply via RSTIN by connecting it through an external resistor divider. With a fixed 0.63V internal reference, use R1 = R2 × (1.8V / 0.63V − 1) ≈ 1.86 × R2. Selecting R2 = 250kΩ yields R1 ≈ 465kΩ. This configuration maintains high input impedance (>100MΩ), minimizing current draw while achieving accurate 1.8V threshold detection as verified in the Applications Information section.

What is the minimum VCC voltage at which MAX6456UT46S+T guarantees valid RESET output operation?

The MAX6456UT46S+T guarantees valid RESET output logic state down to VCC = 1.0V, as explicitly stated in the Absolute Maximum Ratings and Electrical Characteristics tables. Below 1.0V, current-sinking capability degrades and RESET may float; this specification is measured with ISINK = 50µA for open-drain outputs and is validated across the full −40°C to +85°C temperature range per the datasheet's operating conditions.

Does MAX6456UT46S+T require external pullup resistors on its outputs?

Yes, MAX6456UT46S+T requires external pullup resistors on both RESET and MROUT pins because they are active-low open-drain outputs. The datasheet specifies that these outputs must be connected to an external pullup to a logic-compatible voltage (0–6V). Typical values range from 10kΩ to 100kΩ depending on bus capacitance and rise-time requirements; omission causes outputs to remain floating and nonfunctional.