Analog Devices Inc./Maxim Integrated MAX6344ZUT

Overview

MAX6344ZUT from Maxim Integrated is a precision 6-pin SOT23 microprocessor supervisory circuit with active-high push-pull reset output, factory-trimmed 2.33V VCC reset threshold, +1.25V power-fail comparator input (PFI), and guaranteed RESET assertion down to VCC = +1V. It monitors supply integrity in battery-powered systems and provides early warning of power failure via PFO output.

For engineers reviewing the MAX6344ZUT datasheet, MAX6344ZUT pinout, MAX6344ZUT application, or MAX6344ZUT equivalent, key selection criteria include its active-high reset logic, 100ms minimum reset timeout, SOT23-6 package compatibility, and dual-monitoring capability (VCC + auxiliary supply via PFI).

Technical Context

The MAX6344ZUT implements a precision bandgap-based voltage reference for both the 2.33V VCC reset comparator and the 1.25V PFI comparator. Its reset generator guarantees valid logic levels on the active-high RESET output across the full operating temperature range (–40°C to +125°C) and supply range (+1V to +5.5V).

It features debounced CMOS-compatible MR input with 1µs minimum pulse width rejection, and PFO output responds to PFI voltage crossing 1.25V with typical delay under 3µs. The device requires no external components for basic reset supervision and supports bidirectional µP reset I/O interfacing via buffered output.

Key Specifications

Pinout & Package

MAX6344ZUT is housed in a 6-pin SOT23-6 package (JEDEC MO-178AA), 2.9mm × 1.6mm × 1.1mm, lead-free compatible (top mark: AADV).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6342ZUT-T and TLV809EZDBZR, the MAX6344ZUT uniquely delivers active-high reset logic with integrated PFI/PFO monitoring in the same SOT23-6 footprint-enabling simpler µP interface and dual-rail supervision without adding components or board area.

Availability

MAX6344ZUT is available at Aetrix Electronics and suitable for portable/battery-powered equipment, telecom equipment, and multivoltage systems requiring stable component supply, long-term lifecycle support, and guaranteed automotive-grade temperature performance.

Supply support for MAX6344ZUT 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 demanding industrial, automotive, and communications applications.

The MAX6342–MAX6345 family was engineered specifically for robust, low-power microprocessor supervision in harsh environments-featuring factory-trimmed thresholds, wide temperature operation, and integrated power-fail warning to replace discrete solutions.

FAQ

What is the exact reset threshold voltage for MAX6344ZUT?

The MAX6344ZUT has a factory-trimmed VCC reset threshold of 2.33V, with a maximum tolerance of ±25mV over the full operating temperature range (–40°C to +125°C). This value is laser-trimmed during production and specified in the Electrical Characteristics table of the MAX6342–MAX6345 datasheet. The 'Z' suffix explicitly denotes the 2.33V variant, and the MAX6344ZUT maintains this threshold across its entire supply range (+1V to +5.5V).

Does MAX6344ZUT provide an active-high or active-low reset output?

The MAX6344ZUT provides an active-high push-pull reset output on pin 6 (RESET). During normal operation (VCC ≥ 2.33V and MR high), the output is driven high. It goes low only when VCC falls below the 2.33V threshold or when the MR pin is pulled low. This differs from the MAX6342ZUT-T (active-low) and MAX6343ZUT-T (open-drain active-low), making the MAX6344ZUT ideal for µPs with active-high reset inputs.

Can MAX6344ZUT monitor a second voltage rail besides VCC?

Yes, the MAX6344ZUT can monitor a second voltage rail using its PFI (pin 3) and PFO (pin 4) pins. By connecting a resistor divider from the auxiliary rail to PFI, the device triggers PFO low when the divided voltage falls below +1.25V. For example, to monitor a 5V rail for early failure, a 2:1 divider yields 2.5V at PFI-trip occurs when input drops to ~2.5V × (1.25/2.5) = 1.25V at PFI, corresponding to ~2.5V on the 5V rail. This function is fully supported in the MAX6344ZUT and documented in the Applications Information section.

What is the minimum reset pulse width guaranteed by MAX6344ZUT?

The MAX6344ZUT guarantees a minimum reset pulse width (tRP) of 100ms after VCC rises above the 2.33V threshold or after the MR input transitions from low to high. This timeout is internally generated and temperature-compensated, ensuring reliable µP initialization across –40°C to +125°C. Typical values range from 180ms to 280ms depending on temperature, but the 100ms minimum is production-tested and guaranteed for all MAX6344ZUT units.

Is MAX6344ZUT compatible with lead-free soldering processes?

Yes, the MAX6344ZUT is available in lead-free packaging. Per Maxim's ordering information, the '+T' suffix denotes lead-free construction (e.g., MAX6344ZUT+T), while '-T' indicates leaded. The device is rated for lead-free reflow profiles up to +300°C for 10 seconds, and its SOT23-6 package meets JEDEC J-STD-020 moisture sensitivity level 1 (MSL-1), allowing unlimited floor life at ≤30°C/85% RH. Both variants share identical electrical specifications and thermal performance.