Analog Devices Inc./Maxim Integrated MAX6345RUT

Overview

MAX6345RUT from Maxim Integrated is a precision 6-pin SOT23 microprocessor supervisory circuit with dual push-pull reset outputs (active-high RESET and active-low RESET), factory-trimmed 2.63V VCC reset threshold, +1.25V power-fail comparator input (PFI), and guaranteed reset assertion 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 MAX6345RUT datasheet, MAX6345RUT pinout, MAX6345RUT application, or MAX6345RUT equivalent, key selection considerations include its dual-reset output configuration, 2.63V threshold accuracy over –40°C to +125°C, PFI/PFO monitoring capability, and SOT23-6 package compatibility with space-constrained portable and telecom designs.

Technical Context

The MAX6345RUT integrates a precision bandgap reference, reset comparator with hysteresis, power-fail comparator (1.25V internal reference), and dual independent reset drivers - one active-high push-pull (RESET) and one active-low push-pull (RESET). Its reset timeout period is 100ms minimum, with typical 180ms pulse width after VCC rise or MR release.

Unlike MAX6342/MAX6343/MAX6344, the MAX6345RUT replaces the manual-reset (MR) input with a second reset output, eliminating user-initiated reset but enabling simultaneous high- and low-active reset signaling to multiple system components - e.g., CPU and FPGA - without external logic or level-shifting.

Key Specifications

Pinout & Package

MAX6345RUT is housed in a 6-pin SOT23-6 package (JEDEC MO-178AA), 2.9mm × 1.6mm × 1.1mm, with gull-wing leads and exposed pad option (not thermal pad in standard variant).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6342RUT-T and TPS3808G26DBVR, the MAX6345RUT uniquely delivers concurrent active-high and active-low reset signaling without external components - critical for systems requiring independent reset control of heterogeneous processors or safety-critical subsystems.

Availability

MAX6345RUT is available at Aetrix Electronics and suitable for portable computers, telecom equipment, multivoltage systems, embedded control systems, and battery-powered instrumentation requiring stable component supply across extended temperature ranges.

Supply support for MAX6345RUT 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) is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, communications, and computing markets.

The MAX6342–MAX6345 family was designed specifically for robust, low-power microprocessor supervision in harsh environments - delivering precision reset thresholds, power-fail warning, and compact packaging for space- and reliability-constrained applications.

FAQ

What is the exact reset threshold voltage of the MAX6345RUT?

The MAX6345RUT has a factory-trimmed VCC reset threshold of 2.63V, with ±1.5% tolerance 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 under "VTH Reset Threshold" for the "R" suffix variant. The "R" in MAX6345RUT directly denotes the 2.63V threshold option per Maxim's Selector Guide 1.

Does the MAX6345RUT support manual reset functionality?

No, the MAX6345RUT does not include a manual-reset (MR) input. Unlike the MAX6342RUT-T and MAX6343RUT-T, the MAX6345RUT replaces the MR pin with a second reset output (RESET), providing both active-high and active-low push-pull reset signals. If manual reset is required, the MAX6342RUT-T is the functionally matched alternative within the same family.

How is the power-fail warning implemented in the MAX6345RUT?

The MAX6345RUT implements power-fail warning via its PFI (Power-Fail Input) and PFO (Power-Fail Output) pins. The internal +1.25V reference compares against the voltage applied to PFI. When PFI falls below +1.25V - typically achieved using a resistor divider from a monitored supply - PFO asserts low. This signal can trigger a µP interrupt for controlled shutdown, independent of the main reset outputs.

What are the drive capabilities of the two reset outputs on the MAX6345RUT?

The MAX6345RUT features two push-pull reset outputs: RESET (active-high) and RESET (active-low). RESET sources ≥50µA at VOH ≥ 0.8×VCC; RESET sinks ≥1.2mA at VOL ≤ 0.4V. Both outputs operate reliably down to VCC = +1V and require no external pull resistors - unlike open-drain alternatives such as the MAX6343RUT-T.

Is the MAX6345RUT pin-compatible with other devices in the MAX6342–MAX6345 family?

The MAX6345RUT shares the same 6-pin SOT23-6 package and pinout as all members of the MAX6342–MAX6345 family: Pin 1 = VCC, Pin 2 = GND, Pin 3 = PFI, Pin 4 = PFO, Pin 5 = RESET, Pin 6 = RESET. However, it is not functionally pin-compatible with MAX6342/MAX6343/MAX6344 due to the absence of MR and presence of dual reset outputs - PCB layout must allocate Pin 5 and Pin 6 for reset signaling, not MR.