Analog Devices Inc./Maxim Integrated MAX6345SUT

Overview

MAX6345SUT from Maxim Integrated is a precision 6-pin SOT23 microprocessor supervisory circuit with dual active-high and active-low push-pull reset outputs, factory-trimmed 2.93V VCC reset threshold (S-suffix), +1.25V power-fail comparator input, and guaranteed RESET validity down to VCC = +1V. It monitors supply integrity in multivoltage embedded systems and provides early power-fail warning for orderly shutdown.

For engineers reviewing the MAX6345SUT datasheet, MAX6345SUT pinout, MAX6345SUT application, or MAX6345SUT equivalent, this device supports critical reset timing control, dual-output reset coordination, power-fail detection at 1.25V, and operation across -40°C to +125°C industrial temperature range - key selection criteria for portable, telecom, and battery-powered equipment.

Technical Context

The MAX6345SUT integrates two independent reset generators: one asserting an active-high push-pull RESET output and another asserting an active-low push-pull RESET output, both with 100ms minimum timeout (tRP = 100–280ms). Its internal +1.25V reference feeds a dedicated PFI comparator whose output (PFO) is electrically isolated from reset logic.

Unlike MAX6342/MAX6343/MAX6344, the MAX6345SUT replaces the MR input with a second reset output, eliminating manual reset capability but enabling simultaneous high- and low-active reset signaling to multiple system components - e.g., MCU and FPGA - without external logic or level-shifting.

Key Specifications

Pinout & Package

MAX6345SUT is housed in a 6-pin SOT23-6 package (JEDEC MO-178AA), 2.9mm × 1.6mm × 1.1mm body, lead-free compatible (SOT top mark: AADZ).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6345SUT, MAX6344SUT-T provides manual reset flexibility at the expense of dual-output coordination, while TPS3808G33DBVR offers lower quiescent current but omits both PFI monitoring and complementary reset signaling - making MAX6345SUT uniquely suited for systems requiring concurrent reset control and predictive power-fail response.

Availability

MAX6345SUT is available at Aetrix Electronics and suitable for portable computers, telecom equipment, networking hardware, and industrial embedded systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6345SUT 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 highly accurate, temperature-stable reset supervision with integrated power-fail detection - engineered specifically for reliability-critical digital systems where supply monitoring must remain functional across wide voltage and thermal margins.

FAQ

What is the exact reset threshold voltage for MAX6345SUT?

The MAX6345SUT has a factory-trimmed nominal VCC reset threshold of 2.93V (S-suffix), with guaranteed tolerance of ±25mV over the full -40°C to +125°C operating temperature range. This value is laser-trimmed during production and specified in the Electrical Characteristics table under VTH parameter for MAX634_S devices. The threshold remains stable across supply voltages from +1.0V to +5.5V.

Does MAX6345SUT support manual reset functionality?

No, MAX6345SUT does not include a manual-reset (MR) input. Unlike MAX6342–MAX6344 variants, the MAX6345SUT replaces the MR pin with a second reset output (active-high RESET), providing dual complementary reset signals instead of user-triggered reset. This design choice prioritizes coordinated system-level reset timing over field-service reset capability.

How is the power-fail warning implemented in MAX6345SUT?

The MAX6345SUT implements power-fail warning via its dedicated PFI (Power-Fail Input) and PFO (Power-Fail Output) pins. PFI compares an external voltage - typically derived from a resistor divider on a secondary supply - against an internal +1.25V reference. When the divided voltage falls below 1.25V, PFO asserts low, enabling early interrupt-driven shutdown before main supply collapse.

What are the drive capabilities of the two reset outputs on MAX6345SUT?

The MAX6345SUT features two push-pull reset outputs: pin 5 (RESET) is active-high with VOH ≥ 0.8×VCC at 50µA source current, and pin 6 (RESET) is active-low with VOL ≤ 0.4V at 1.2mA sink current. Both outputs are fully buffered and require no external pull-up or pull-down resistors, simplifying PCB layout and improving noise immunity compared to open-drain alternatives.

Is MAX6345SUT compatible with lead-free soldering processes?

Yes, MAX6345SUT is available in lead-free packaging. The "-T" suffix denotes leaded packaging, while "+T" indicates lead-free; however, the standard MAX6345SUT-T ordering part number shipped by Maxim is RoHS-compliant and qualified for reflow soldering per JEDEC J-STD-020. The SOT23-6 package withstands peak temperatures up to +260°C for 10 seconds during standard lead-free reflow profiles.