Analog Devices Inc./Maxim Integrated MAX6359TWUT

Overview

The MAX6359TWUT from Maxim Integrated is a dual-voltage microprocessor supervisory circuit with active-low push-pull reset referenced to VCC1, factory-set VCC1 threshold of 3.08V and VCC2 threshold of 1.67V, watchdog timer (46.4s startup / 2.9s normal timeout), and guaranteed RESET validity down to VCC1 ≥ 1.0V or VCC2 ≥ 1.0V - used in multivoltage embedded systems requiring reliable power-on reset and processor activity monitoring.

For engineers reviewing the MAX6359TWUT datasheet, MAX6359TWUT pinout, MAX6359TWUT application, or MAX6359TWUT equivalent, key selection considerations include dual-supply threshold accuracy (±0.05V over temperature), 20µA quiescent current, 100ms min reset pulse width, and SOT23-6 package compatibility with space-constrained industrial controllers and portable instrumentation.

Technical Context

The MAX6359TWUT implements a dual-threshold voltage monitor with independent trip points for VCC1 and VCC2, asserting reset whenever either supply drops below its specified threshold. Its internal watchdog timer operates in two distinct modes: a 46.4s startup timeout (for system initialization) and a 2.9s normal timeout (for runtime fault detection), both cleared by edges on the WDI input.

Reset output is push-pull, referenced to VCC1, with VOL ≤ 0.3V at ISINK = 50µA over full temperature range and VOH ≥ 0.8 × VCC1 at ISOURCE = 350µA. The device guarantees functional reset assertion as long as either VCC1 or VCC2 remains ≥ 1.0V, enabling robust operation during brownout conditions.

Key Specifications

Pinout & Package

MAX6359TWUT is housed in a 6-pin SOT23 package (U6-1 outline, land pattern 90-0175), with 0.95mm pitch, 2.9mm × 1.6mm body, and exposed pad not connected internally.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6359TUT, MAX6359TWUT provides higher VCC2 threshold (1.67V vs. 1.58V) for improved noise margin on 1.8V rails; compared with TPS3808G33DBVR, it adds critical dual-supply monitoring and watchdog support but requires SOT23-6 layout and additional WDI routing.

Availability

MAX6359TWUT is available at Aetrix Electronics and suitable for industrial PLC controllers, portable medical monitors, and multivoltage embedded gateways requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6359TWUT 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, communications, and computing applications.

The MAX6351–MAX6360 family delivers dual- and triple-voltage microprocessor supervisors optimized for reliability-critical embedded systems where simultaneous rail monitoring and watchdog protection are mandatory.

FAQ

What is the exact VCC1 and VCC2 threshold voltage for MAX6359TWUT?

The MAX6359TWUT has a factory-set VCC1 threshold of 3.08V (±0.05V over -40°C to +85°C) and VCC2 threshold of 1.67V (±0.05V over same range), as defined by the "TW" suffix in the Voltage Threshold Levels table. These values are laser-trimmed during production and do not require external calibration. The MAX6359TWUT datasheet specifies these thresholds under Electrical Characteristics with min/typ/max limits confirmed across temperature.

Does MAX6359TWUT support watchdog functionality, and what are its timeout periods?

Yes, MAX6359TWUT includes a dual-mode watchdog timer. After power-up or reset, it enters a 46.4s startup timeout period to allow system initialization; thereafter, it switches to a 2.9s normal timeout period. Both periods are cleared by rising or falling edges on the WDI pin. The MAX6359TWUT watchdog is fully integrated - no external components are needed, and timeout values are fixed per device variant.

What is the reset output type and drive capability of MAX6359TWUT?

The MAX6359TWUT features an active-low push-pull reset output (RST pin) referenced to VCC1. It guarantees VOL ≤ 0.3V at ISINK = 50µA over full temperature range and VOH ≥ 0.8 × VCC1 at ISOURCE = 350µA. This eliminates the need for an external pull-up resistor and allows direct interfacing with standard CMOS μP reset inputs. The MAX6359TWUT output remains valid as long as VCC1 ≥ 1.0V or VCC2 ≥ 1.0V.

Can MAX6359TWUT monitor three voltage rails?

No, MAX6359TWUT monitors exactly two voltage rails: VCC1 and VCC2. It belongs to the MAX6358/MAX6359/MAX6360 subgroup, which lacks the RSTIN pin used by MAX6355/MAX6356/MAX6357 for third-rail monitoring. The MAX6359TWUT pinout shows only VCC1, VCC2, RST, MR, WDI, and GND - no dedicated third-input terminal. For triple-voltage supervision, consider MAX6356TUT (3.08V/1.67V/1.22V) instead.

What package and RoHS status does MAX6359TWUT use?

MAX6359TWUT is supplied in a 6-pin SOT23 package (U6-1 outline, land pattern 90-0175) with lead(Pb)-free termination. The "-T" suffix denotes tape-and-reel packaging; RoHS compliance is indicated by the "+T" ordering variant (e.g., MAX6359TWUT+T). The MAX6359TWUT device meets JEDEC J-STD-020 moisture sensitivity level 1 and is rated for reflow soldering per industry standards.