Analog Devices Inc./Maxim Integrated MAX6456UT16S+T

Overview

MAX6456UT16S+T from Maxim Integrated is a dual-voltage microprocessor supervisor IC with separate active-low open-drain VCC reset and manual reset outputs, 1.575V factory-set VCC reset 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 rails.

For engineers reviewing the MAX6456UT16S+T datasheet, MAX6456UT16S+T pinout, MAX6456UT16S+T application, or MAX6456UT16S+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 precise 1.575V VCC threshold with ±15mV tolerance at +25°C.

Technical Context

The MAX6456UT16S+T implements a dual-comparator architecture: one precision bandgap-based comparator monitors VCC against a fixed 1.575V threshold (±15mV typ), while a second high-impedance comparator monitors RSTIN against a fixed 0.630V reference (±20mV over temperature). Both comparators feed independent reset logic paths.

Its MR input controls both MROUT and RESET outputs via an internal timer that distinguishes short pulses (<3.36s) - asserting only MROUT - from extended assertions (≥3.36s) - asserting both MROUT and RESET for coordinated interrupt-and-reboot sequences. All outputs are open-drain with 1µA leakage and 0.4V VOL at 3.2mA sink.

Key Specifications

Pinout & Package

Package: SOT23-6, lead(Pb)-free, RoHS-compliant, 1.6mm × 2.9mm footprint.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6455UT16S+T, the MAX6456UT16S+T provides open-drain flexibility for bus sharing and level translation, while versus TPS3808G15DBVR it delivers dual-rail monitoring, adjustable threshold, and programmable soft/hard reset sequencing - critical for complex embedded systems requiring data preservation before reboot.

Availability

MAX6456UT16S+T is available at Aetrix Electronics and suitable for set-top boxes, DVD players, cable modems, MP3 players, and industrial equipment requiring stable component supply with guaranteed long-term manufacturability.

Supply support for MAX6456UT16S+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 in industrial, medical, and consumer markets.

The MAX6453–MAX6456 family was engineered specifically for dual-rail microprocessor supervision with integrated soft-reset interrupt capability, targeting cost-sensitive, space-constrained embedded systems needing robust brownout and user-initiated recovery.

FAQ

What is the exact VCC reset threshold voltage for MAX6456UT16S+T?

The MAX6456UT16S+T has a factory-set VCC reset threshold of 1.575V, with a typical tolerance of ±15mV at +25°C and ±25mV over the full –40°C to +85°C operating range. This value is laser-trimmed during production and documented in Table 1 of the MAX6453–MAX6456 datasheet under suffix "16". The threshold remains stable with 60ppm/°C tempco.

Does MAX6456UT16S+T support monitoring a 1.2V supply using the RSTIN pin?

Yes, MAX6456UT16S+T supports monitoring a 1.2V supply via RSTIN using an external resistor divider. With a fixed 0.630V internal reference, a standard solution uses R2 = 250kΩ and calculates R1 = R2 × (1.2V / 0.63V – 1) ≈ 226kΩ. The resulting threshold accuracy is ±20mV over temperature, and input bias current is only ±25nA, minimizing divider error.

How does the manual reset function differ between MAX6456UT16S+T and MAX6454UT16S+T?

Unlike MAX6454UT16S+T - which asserts only MROUT on MR low - the MAX6456UT16S+T asserts both MROUT and RESET when MR is held low for ≥3.36s. This enables coordinated interrupt-and-reboot behavior: short MR pulses trigger NMI via MROUT alone, while long pulses force full system reset via RESET, a feature absent in MAX6454UT16S+T.

What is the minimum VCC voltage at which MAX6456UT16S+T guarantees valid RESET output operation?

MAX6456UT16S+T guarantees valid RESET output logic state down to VCC = 1.0V. Below this, current-sinking capability degrades rapidly. The device remains functional across 1.0V–5.5V, and RESET is specified to drive low to 0.4V at 3.2mA sink when VCC ≥ 4.25V, ensuring compatibility with 3.3V and 5V µP reset inputs.

Can MAX6456UT16S+T be used in a system with a 2.5V microprocessor reset input?

Yes, MAX6456UT16S+T can interface to a 2.5V µP reset input because its open-drain RESET output supports level translation: connect the external pullup resistor to the 2.5V supply rail instead of VCC. The output leakage is only 1µA when deasserted, and VOL is 0.4V max at 3.2mA sink, ensuring clean low-state recognition by the 2.5V logic.