Analog Devices Inc./Maxim Integrated MAX6359UVUT

Overview

The MAX6359UVUT 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 threshold pair, integrated watchdog timer (46.4s startup / 2.9s normal timeout), and guaranteed RESET validity down to VCC1 = 1.0V or VCC2 = 1.0V. It operates across –40°C to +85°C in multivoltage embedded systems requiring reliable power-on reset and processor activity monitoring.

For engineers reviewing the MAX6359UVUT datasheet, MAX6359UVUT pinout, MAX6359UVUT application, or MAX6359UVUT equivalent, key selection criteria include dual-supply threshold accuracy (±1.5% over temperature), 20µA quiescent current, 100ms minimum reset pulse width, and watchdog input timing compatibility with ARM Cortex-M boot sequences and FPGA configuration cycles.

Technical Context

The MAX6359UVUT implements independent precision voltage comparators for VCC1 and VCC2, each with 20ppm/°C tempco and 500mV hysteresis (VTH/500). Reset assertion occurs if either supply drops below its respective threshold, and the active-low RST output remains valid as long as at least one supply exceeds +1.0V.

Its watchdog timer features two distinct modes: a 46.4s startup timeout (min 25.6s) for system initialization, and a 2.9s normal timeout (min 1.6s) triggered by missing WDI edges. The manual-reset input is debounced and TTL/CMOS-compatible, with glitch rejection of 100ns.

Key Specifications

Pinout & Package

MAX6359UVUT is housed in a 6-pin SOT23 package (U6-1 outline, 90-0175 land pattern), with 1.27mm pitch, 2.9mm × 1.6mm footprint, and exposed pad optional for thermal enhancement.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6359UVUT, MAX6359UTUT offers identical architecture and watchdog timing but targets 3.3V primary rails, whereas TPS3808G33DBVR reduces cost and quiescent current at the expense of dual-supply capability and system-level fault coverage.

Availability

MAX6359UVUT is available at Aetrix Electronics and suitable for industrial PLC controllers, medical handheld diagnostics, and automotive body control modules requiring stable component supply with guaranteed long-term availability and RoHS-compliant packaging.

Supply support for MAX6359UVUT 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, automotive, and computing applications, with emphasis on reliability and integration.

The MAX6351–MAX6360 family delivers dual- and triple-voltage supervision with integrated watchdog timers, targeting multirail embedded systems where power integrity and processor health monitoring are mission-critical.

FAQ

What is the exact reset threshold voltage pair for MAX6359UVUT?

The MAX6359UVUT has factory-set reset thresholds of 2.78V for VCC1 and 1.58V for VCC2, each with ±1.5% tolerance over the full –40°C to +85°C temperature range. These values are laser-trimmed during production and documented in the Voltage-Threshold Levels table of the MAX6351–MAX6360 datasheet. The "UV" suffix explicitly denotes this 2.78V/1.58V combination.

Does MAX6359UVUT provide a reset output referenced to VCC2?

No, MAX6359UVUT provides only a single active-low push-pull reset output (RST) referenced to VCC1, as confirmed by the Pin Description table and Selector Guide. Unlike the MAX6354/MAX6357/MAX6360 variants, MAX6359UVUT does not include an RST2 output tied to VCC2. Its reset assertion depends solely on VCC1 and VCC2 thresholds but drives only the VCC1-referenced RST pin.

What are the watchdog timeout periods for MAX6359UVUT?

MAX6359UVUT features a dual-mode watchdog timer with a 46.4s startup timeout (minimum 25.6s) after power-on or reset, and a 2.9s normal timeout (minimum 1.6s) during steady-state operation. The timer resets on any WDI edge and begins the normal timeout period either after the startup period expires or upon the first WDI transition before startup completes.

Can MAX6359UVUT operate with supply voltages below 1.2V?

MAX6359UVUT guarantees RESET output validity as long as either VCC1 ≥ 1.0V or VCC2 ≥ 1.0V, but its specified operating range requires VCC1 and VCC2 ≥ 1.2V for full functionality per Electrical Characteristics. Below 1.2V, the device may not reliably monitor thresholds or sustain internal biasing, though the reset output remains asserted until both supplies fall below 1.0V.

Is MAX6359UVUT pin-compatible with other devices in the MAX6351–MAX6360 family?

Yes, MAX6359UVUT uses the standard 6-pin SOT23 package (U6-1) and shares identical pinout with all 6-pin variants in the MAX6351–MAX6360 series, including MAX6351, MAX6355–MAX6358, and MAX6360. Pin 1 is RST, Pin 2 is GND, Pin 3 is MR, Pin 4 is VCC2, Pin 5 is WDI, and Pin 6 is VCC1 - verified in the Pin Configurations section of the datasheet.