Analog Devices Inc./Maxim Integrated MAX6353UWUK+T

Overview

MAX6353UWUK+T from Maxim Integrated is a dual-voltage microprocessor supervisory circuit with active-low push-pull reset referenced to VCC1, precision factory-set thresholds of 2.78V (VCC1) and 1.67V (VCC2), 20µA supply current, and guaranteed RESET validity down to VCC1 ≥ 1.0V or VCC2 ≥ 1.0V - used in multivoltage embedded systems requiring reliable power-on and brownout detection.

For engineers reviewing the MAX6353UWUK+T datasheet, MAX6353UWUK+T pinout, MAX6353UWUK+T application, or MAX6353UWUK+T equivalent, key selection criteria include dual-supply threshold accuracy, reset pulse width (100–280ms), manual-reset debouncing, SOT23-5 package compatibility, and absence of watchdog timer functionality in this variant.

Technical Context

The MAX6353UWUK+T monitors two independent supply rails (VCC1 and VCC2) and asserts its single active-low push-pull RST output when either falls below its respective factory-trimmed threshold (2.78V/1.67V). Reset remains valid as long as at least one supply exceeds +1.0V, enabling robust operation during asymmetric rail collapse.

It features a debounced TTL/CMOS-compatible manual-reset input (MR), 100ms minimum power-on-reset pulse width, and no internal watchdog timer - distinguishing it from MAX6359/MAX6360 variants. The device operates across –40°C to +85°C and draws only 20µA typical supply current.

Key Specifications

Pinout & Package

MAX6353UWUK+T is housed in a 5-pin SOT23 package (package code U5-1), with 0.95mm pitch, 2.9mm × 1.6mm body size, and exposed pad not present. Pin 1 is RST (active-low push-pull, referenced to VCC1), Pin 2 is GND, Pin 3 is MR (manual reset input), Pin 4 is VCC2, and Pin 5 is VCC1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6353UVUK+T and TPS3808G18DBVR, the MAX6353UWUK+T uniquely delivers matched dual-threshold supervision (2.78V/1.67V) in a single SOT23-5 package with 20µA current and guaranteed 1.0V reset validity - making it optimal for space-constrained multivoltage designs where coordinated reset timing is essential.

Availability

MAX6353UWUK+T is available at Aetrix Electronics and suitable for industrial PLC controllers, battery-powered IoT sensors, and multivoltage embedded systems requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6353UWUK+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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, communications, and computing applications.

The MAX6351–MAX6360 family was designed to replace discrete supervisory solutions in multivoltage systems - delivering precision dual/three-rail monitoring, low power, and compact SOT23 packaging for space- and reliability-critical embedded designs.

FAQ

What is the function of the MR pin on the MAX6353UWUK+T?

The MR (Manual Reset) pin on the MAX6353UWUK+T is an active-low, debounced input that forces the RST output low when asserted. It remains active for the reset timeout period (100–280ms) after release, ensuring reliable reset initiation independent of supply conditions. The MAX6353UWUK+T internal filter rejects sub-100ns glitches, eliminating need for external RC networks. MR must not exceed VCC1 voltage.

Does the MAX6353UWUK+T include a watchdog timer?

No, the MAX6353UWUK+T does not include a watchdog timer. Watchdog functionality is exclusive to the MAX6358/MAX6359/MAX6360 variants in the same family. The MAX6353UWUK+T provides only dual-voltage monitoring and manual reset - confirmed by its pinout (no WDI pin) and product selector guide. For watchdog capability, consider MAX6359UWUT+T instead.

What are the absolute maximum ratings for VCC1 and VCC2 on the MAX6353UWUK+T?

The absolute maximum rating for both VCC1 and VCC2 on the MAX6353UWUK+T is –0.3V to +6.0V relative to GND. Exceeding these limits may cause permanent damage. The recommended operating range is +1.2V to +5.5V for both supplies at –40°C to +85°C. The MAX6353UWUK+T guarantees valid RST output as long as either VCC1 ≥ 1.0V or VCC2 ≥ 1.0V - a key design margin beyond absolute minima.

Can the MAX6353UWUK+T monitor a 3.3V rail and a 1.2V rail simultaneously?

Yes, the MAX6353UWUK+T can monitor a 3.3V rail (as VCC1) and a 1.2V rail (as VCC2) simultaneously - but only if the 1.2V rail meets the VCC2 threshold requirement of 1.67V. Since 1.2V < 1.67V, it will continuously assert reset. To supervise a true 1.2V rail, select a variant with lower VCC2 threshold (e.g., MAX6353RVUK+T: VCC2 = 2.63V is still too high; no variant in this family supports ≤1.2V VCC2). The MAX6353UWUK+T is optimized for rails ≥1.67V (e.g., 1.8V LDO outputs).

What is the reset output type and drive strength of the MAX6353UWUK+T?

The MAX6353UWUK+T features an active-low push-pull RST output referenced to VCC1. It drives low with 1.2mA sink capability at VCC1 ≥ 2.7V (VOL ≤ 0.3V) and sources weakly (VOH = 0.8 × VCC1 at ISOURCE = 350µA) only in _W/_V suffix versions. This eliminates need for external pull-up resistors and provides robust noise immunity. The output remains valid down to VCC1 = 1.0V - a critical feature for brownout resilience in the MAX6353UWUK+T.