Analog Devices Inc./Maxim Integrated MAX6359UVUT-T

Overview

The MAX6359UVUT-T from Maxim Integrated is a dual-voltage microprocessor supervisory circuit with active-low push-pull reset output referenced to VCC1, 2.78V/1.58V factory-set reset thresholds, watchdog timer (46.4s startup / 2.9s normal timeout), and guaranteed operation down to VCC1 = 1.0V or VCC2 = 1.0V. It monitors two independent supply rails in multivoltage embedded systems requiring reliable power-on reset and processor activity supervision.

For engineers reviewing the MAX6359UVUT-T datasheet, MAX6359UVUT-T pinout, MAX6359UVUT-T application, or MAX6359UVUT-T equivalent, key selection criteria include dual-supply threshold accuracy, watchdog timing modes, push-pull reset drive capability, SOT23-6 package compatibility, and guaranteed reset validity at low supply voltages.

Technical Context

The MAX6359UVUT-T implements a dual-threshold comparator architecture monitoring VCC1 and VCC2 independently; reset asserts if either supply falls below its respective trip point (2.78V ±0.08V for VCC1, 1.58V ±0.05V for VCC2). Its watchdog timer features two distinct timeout modes: a 46.4s startup period after power-up or manual reset, followed by a 2.9s normal timeout requiring periodic WDI transitions.

Reset output is an active-low push-pull driver referenced to VCC1, capable of sinking 1.2mA at VCC1 ≥ 2.7V (VOL ≤ 0.3V) and sourcing 350µA (VOH ≥ 0.8 × VCC1) for _W/_V suffix variants. The device guarantees valid reset state as long as either VCC1 or VCC2 remains above +1.0V, enabling robust operation during brownout conditions.

Key Specifications

Pinout & Package

MAX6359UVUT-T is housed in a 6-pin SOT23 package (U6-1 outline, 90-0175 land pattern), with 1.0mm pitch, 2.9mm × 1.6mm footprint, and lead(Pb)-free construction (suffix -T denotes RoHS-compliant packaging).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-voltage supervisory applications.

Compared with MAX6359UVUT-T, the MAX6359UT-T offers identical functionality and electrical performance with packaging variation only, while the TPS3808G33DBVR lacks dual-voltage capability and watchdog support-making it unsuitable as a drop-in replacement but viable only in fundamentally simpler power-monitoring contexts.

Availability

MAX6359UVUT-T is available at Aetrix Electronics and suitable for industrial PLC controllers, portable medical devices, automotive infotainment modules, and edge AI sensor nodes requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for MAX6359UVUT-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 industrial, automotive, communications, and computing applications.

The MAX6351–MAX6360 family delivers dual- and triple-voltage microprocessor supervisors optimized for multirail embedded systems needing coordinated reset sequencing, brownout resilience, and watchdog-based software fault detection.

FAQ

What is the exact reset threshold voltage for VCC1 and VCC2 on the MAX6359UVUT-T?

The MAX6359UVUT-T has factory-set reset thresholds of 2.78V ±0.08V for VCC1 and 1.58V ±0.05V for VCC2, specified over the full -40°C to +85°C operating temperature range. These values correspond to the "UV" suffix in the part number and are guaranteed by design, not production tested, with 20ppm/°C tempco.

Does the MAX6359UVUT-T provide a push-pull or open-drain reset output?

The MAX6359UVUT-T provides an active-low push-pull reset output (RST pin) referenced to VCC1, capable of both sourcing and sinking current. This differs from open-drain variants like MAX6358UVUT-T and eliminates the need for an external pull-up resistor in most MCU interface configurations.

How does the watchdog timer on the MAX6359UVUT-T operate during system startup?

The MAX6359UVUT-T watchdog timer initiates a 46.4s startup timeout period after any reset event (power-up, MR assertion, or watchdog timeout). During this interval, no WDI transitions are required. Once the startup period expires-or upon the first valid WDI edge before expiry-the timer switches to 2.9s normal timeout mode, demanding regular updates to prevent reset assertion.

Can the MAX6359UVUT-T remain functional if one supply rail drops below 1.0V?

No-the MAX6359UVUT-T guarantees valid reset output only as long as *either* VCC1 or VCC2 remains above +1.0V. If both supplies fall below 1.0V simultaneously, reset behavior is undefined. However, the device continues asserting reset correctly down to 1.0V on either rail individually, supporting robust brownout handling.

What is the supply current consumption of the MAX6359UVUT-T under typical operating conditions?

The MAX6359UVUT-T draws 20µA typical supply current (ICC1 + ICC2) when VCC1 = 5.5V and VCC2 = 3.6V, with all I/O pins open. This ultra-low quiescent current is maintained across the full -40°C to +85°C temperature range, making the MAX6359UVUT-T suitable for battery-critical applications.