Analog Devices Inc./Maxim Integrated MAX6357TWUT+T

Overview

MAX6357TWUT+T from Maxim Integrated is a triple-voltage microprocessor supervisory circuit with active-low push-pull reset output referenced to VCC2, 3.08V VCC1 threshold, 1.67V VCC2 threshold, and integrated adjustable reset comparator input (RSTIN) for monitoring a third voltage at 1.22V nominal. It operates over –40°C to +85°C in 6-pin SOT23 and supports multivoltage embedded systems requiring precise power-fail detection and system initialization.

For engineers reviewing the MAX6357TWUT+T datasheet, MAX6357TWUT+T pinout, MAX6357TWUT+T application, or MAX6357TWUT+T equivalent, key selection criteria include its dual-supply monitoring capability, RSTIN-based third-voltage supervision, guaranteed RESET validity down to VCC1/VCC2 = 1.0V, and compatibility with battery-backed or low-voltage industrial controllers.

Technical Context

The MAX6357TWUT+T implements a precision dual-threshold comparator architecture that asserts reset when either VCC1 drops below 3.08V or VCC2 falls below 1.67V, with ±0.05V typical threshold accuracy over temperature. Its RSTIN input provides a fixed 1.22V reference for external resistive divider-based monitoring of a third supply, enabling true triple-voltage supervision without external comparators.

Reset assertion is guaranteed as long as either VCC1 ≥ 1.0V or VCC2 ≥ 1.0V, and the device features debounced TTL/CMOS-compatible manual-reset input with <1µs glitch rejection. Unlike watchdog-equipped variants (e.g., MAX6359), MAX6357TWUT+T omits WDI functionality but retains full support for push-pull RST2 output referenced to VCC2 and MR-controlled reset timing.

Key Specifications

Pinout & Package

MAX6357TWUT+T uses a 6-pin SOT23 package with exposed pad (U6-1 outline), footprint code 90-0175, and RoHS-compliant lead-free construction indicated by "+T" suffix.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6356TWUT+T, MAX6357TWUT+T provides VCC2-referenced reset output ideal for driving loads powered from the lower-voltage rail, while both share identical threshold accuracy, RSTIN functionality, and temperature range - making them complementary rather than interchangeable choices.

Availability

MAX6357TWUT+T is available at Aetrix Electronics and suitable for industrial PLC I/O modules, battery-powered data loggers, medical point-of-care devices, and automotive body control modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6357TWUT+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 high-performance analog and mixed-signal ICs for industrial, communications, computing, and consumer applications.

The MAX6351–MAX6360 product line delivers precision multivoltage supervision for embedded systems where reliability, low power, and minimal external components are critical - especially in space-constrained or battery-operated equipment.

FAQ

What is the exact reset threshold voltage for VCC1 on the MAX6357TWUT+T?

The MAX6357TWUT+T has a factory-set VCC1 threshold of 3.08V, with tolerance of ±0.05V at +25°C and ±0.08V over the full –40°C to +85°C operating range. This value is confirmed in the Voltage Threshold Levels table and Electrical Characteristics section of the official datasheet, where "TW" suffix maps to 3.08V for VCC1 and 1.67V for VCC2.

Does the MAX6357TWUT+T include a watchdog timer function?

No, the MAX6357TWUT+T does not include a watchdog timer. Watchdog functionality is exclusive to the MAX6358/MAX6359/MAX6360 variants. The MAX6357TWUT+T belongs to the MAX6355/MAX6356/MAX6357 subgroup, which adds the RSTIN input for third-voltage monitoring but omits WDI. This distinction is clearly defined in the Selector Guide and Pin Description sections.

What is the purpose of the RSTIN pin on the MAX6357TWUT+T?

The RSTIN pin on the MAX6357TWUT+T provides an adjustable reset comparator input with a fixed 1.22V internal reference. It enables monitoring of a third supply voltage using an external resistive divider - for example, scaling a 5V rail down to 1.22V to trigger reset when the original voltage drops below ~5.0V. The RSTIN input is powered by VCC1 and must not exceed VCC1 voltage, as specified in the Absolute Maximum Ratings.

Can the MAX6357TWUT+T operate with VCC1 and VCC2 voltages below 2.0V?

Yes, the MAX6357TWUT+T guarantees correct reset output behavior as long as either VCC1 ≥ 1.0V or VCC2 ≥ 1.0V, per the Electrical Characteristics table. While the specified operating range starts at 1.2V for full parameter guarantee, the device maintains RESET validity down to 1.0V on either supply - a key feature for brownout recovery in low-voltage systems.

What package type and RoHS status does the MAX6357TWUT+T use?

The MAX6357TWUT+T uses a 6-pin SOT23 package (outline U6-1, land pattern 90-0175) with lead-free RoHS-compliant construction. The "+T" suffix explicitly denotes lead-free packaging, distinguishing it from the leaded "-T" version. This is confirmed in the Ordering Information and Package Information sections of the datasheet.