Analog Devices Inc./Maxim Integrated MAX6345TUT+

Overview

MAX6345TUT+ from Maxim Integrated is a dual-output microprocessor supervisory circuit in SOT23-6 packaging, providing both active-high push-pull RESET and active-low push-pull RESET outputs with factory-trimmed 3.08V VCC reset threshold, +1.25V PFI comparator for power-fail/low-battery warning, and guaranteed reset validity down to VCC = +1V. It serves as a system-level power integrity monitor in multivoltage embedded systems requiring reliable brownout protection and orderly shutdown signaling.

For engineers reviewing the MAX6345TUT+ datasheet, MAX6345TUT+ pinout, MAX6345TUT+ application, or MAX6345TUT+ equivalent, key selection considerations include its dual-reset output architecture, precise 3.08V threshold tolerance (±25mV over -40°C to +125°C), 100ms minimum reset timeout, PFI/PFO monitoring capability, and SOT23-6 footprint compatibility with space-constrained portable and telecom designs.

Technical Context

The MAX6345TUT+ integrates two independent reset generators: one asserting high upon VCC rise above 3.08V (or MR release), the other asserting low under identical conditions-enabling simultaneous reset control of multiple voltage domains or bidirectional µP interfaces. Its internal +1.25V reference drives a dedicated PFI comparator whose output (PFO) operates independently of reset logic.

Reset assertion timing is governed by a fixed 100–280ms timeout window after VCC crosses threshold or MR deasserts, with glitch immunity up to 1µs on MR and transient rejection of ≤12µs negative-going VCC excursions at 100mV overdrive. All outputs are push-pull, eliminating external pull resistors required by open-drain variants like MAX6343.

Key Specifications

Pinout & Package

Package: 6-pin SOT23-6, 1.6mm × 2.9mm × 1.1mm body, surface-mount, lead-free (RoHS-compliant).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with MAX6342TUT+, the MAX6345TUT+ eliminates MR complexity and provides native dual-reset coordination; compared with TPS3808G30DBVR, it offers integrated power-fail warning and push-pull drive but no watchdog-making it optimal for deterministic, low-component-count power supervision.

Availability

MAX6345TUT+ is available at Aetrix Electronics and suitable for portable computers, telecom equipment, multivoltage systems, and embedded control systems requiring stable component supply, industrial temperature support, and dual-reset signaling capability.

Supply support for MAX6345TUT+ 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, mixed-signal, and power management ICs for industrial, automotive, communications, and computing applications.

The MAX6342–MAX6345 family delivers compact, factory-trimmed supervisory circuits optimized for reliability-critical digital systems where accurate voltage monitoring, dual-reset control, and power-fail warning are essential.

FAQ

What is the exact reset threshold voltage of the MAX6345TUT+ and how tightly is it specified?

The MAX6345TUT+ has a factory-trimmed VCC reset threshold of 3.08V, with a maximum deviation of ±25mV over the full operating temperature range of –40°C to +125°C. This specification is guaranteed per device and documented in the Electrical Characteristics table of the official datasheet. The 3.08V value corresponds to the "T" suffix in the part number, and the tight tolerance ensures consistent reset behavior without external calibration. The MAX6345TUT+ maintains this accuracy across its entire supply range (+1.0V to +5.5V) and load conditions.

Does the MAX6345TUT+ support manual reset functionality like other members of the MAX6342–MAX6345 family?

No, the MAX6345TUT+ does not include a manual-reset (MR) input. Unlike the MAX6342TUT+, MAX6343TUT+, and MAX6344TUT+, the MAX6345TUT+ replaces the MR pin with a second reset output-specifically an active-high push-pull RESET. This design choice prioritizes dual-output coordination over user-initiated reset, making the MAX6345TUT+ ideal for fully automated systems where reset timing is controlled solely by VCC monitoring. Pin 5 is RESET (active-high), and pin 6 is RESET (active-low); no MR terminal exists on the MAX6345TUT+.

How does the PFI/PFO function work in the MAX6345TUT+, and what is its reference voltage?

The MAX6345TUT+ features a dedicated power-fail comparator with PFI (Power-Fail Input) and PFO (Power-Fail Output). Its internal reference is a precision +1.25V bandgap voltage, fixed and trimmed at wafer test. When the voltage applied to PFI falls below +1.25V, PFO is driven low (open-drain, so requires external pull-up). This allows monitoring of auxiliary supplies-e.g., connecting a resistor divider from a 5V rail to PFI sets trip point at 5V × (R2/(R1+R2)) = 1.25V. The PFO signal is fully independent of the reset outputs, enabling early-warning interrupts without affecting system reset state.

What are the drive capabilities of the two RESET outputs on the MAX6345TUT+?

Both RESET outputs on the MAX6345TUT+ are push-pull, eliminating need for external pull resistors. The active-high RESET (pin 5) sources ≥0.8×VCC at 50µA and sinks ≤0.4V at 1.2mA. The active-low RESET (pin 6) sinks ≤0.4V at 1.2mA and sources ≥0.8×VCC at 50µA. These specifications ensure direct interfacing with standard CMOS and TTL inputs across the full +1.0V to +5.5V supply range. Unlike the open-drain RESET of MAX6343TUT+, the MAX6345TUT+'s push-pull outputs provide defined logic states even when VCC is near minimum.

Is the MAX6345TUT+ compatible with modern RoHS and lead-free assembly processes?

Yes, the MAX6345TUT+ is manufactured in lead-free packaging and fully compliant with RoHS Directive 2011/65/EU. The "+" suffix explicitly denotes lead-free construction, replacing the legacy "-T" suffix used for leaded versions. It supports standard reflow profiles including JEDEC J-STD-020 moisture sensitivity level (MSL) 1, and its SOT23-6 package is qualified for Pb-free soldering up to 260°C peak temperature. The device undergoes rigorous qualification per AEC-Q200 for stress testing, ensuring reliability in industrial and automotive applications where lead-free compliance is mandatory.