Analog Devices Inc. LT4363MPMS-2#PBF

Overview

LT4363MPMS-2#PBF from Analog Devices is a high-voltage surge stopper IC that controls an external N-channel MOSFET to regulate output voltage during overvoltage transients up to 100V, limits current via 50mV SNS–OUT sense threshold, features adjustable UV/OV comparators (1.275V thresholds), and implements auto-retry fault recovery with 0.5V TMR restart threshold. It is used in avionic power systems requiring –55°C to 125°C operation and sustained 80V input.

For engineers reviewing the LT4363MPMS-2#PBF datasheet, LT4363MPMS-2#PBF pinout, LT4363MPMS-2#PBF application, or LT4363MPMS-2#PBF equivalent, key selection considerations include its MP-grade temperature range (–55°C to 125°C), MSOP-12 package with OV pin, 7µA shutdown current, and LT4363-2 auto-restart behavior versus latch-off LT4363-1 variants.

Technical Context

The LT4363MPMS-2#PBF integrates dual precision comparators for UV (1.275V) and OV (1.275V) monitoring, a 50mV current-sense amplifier with foldback to 25mV when OUT < 2V, and a VCC-referenced fault timer with three-phase operation: early warning (TMR = 1.275V → FLT low), turn-off (TMR = 1.375V), and cool-down/restart (TMR = 4.3V → 0.5V). Its GATE driver delivers up to 13V above OUT with 14V clamp and ±100mA pull-down capability.

It operates across 4V–80V VCC, withstands –60V reverse input, supports back-to-back MOSFET reverse protection, and uses a single external capacitor on TMR to set all timing intervals-warning, shutdown, and auto-restart-based on V_DS-dependent charging currents ranging from 4µA (low stress) to 260µA (overcurrent, V_DS = 80V).

Key Specifications

Pinout & Package

LT4363MPMS-2#PBF is housed in a 12-lead plastic MSOP package (4.9mm × 3.0mm × 1.0mm), with exposed pad optional for thermal enhancement. Pin 1 is marked by dot; pin count and layout match standard MSOP-12 footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar surge protection regulator applications.

Compared with LT4363IMS-2#PBF and LT4363HMS-2#PBF, the LT4363MPMS-2#PBF provides unique assurance of operation at –55°C and full qualification per MIL-PRF-38535 requirements-critical for cold-soak avionics, space-qualified payloads, and deep-well instrumentation where component failure is not recoverable.

Availability

LT4363MPMS-2#PBF is available at Aetrix Electronics and suitable for avionic power distribution, industrial hot-swap modules, intrinsic safety barriers, and battery-powered test equipment requiring stable component supply across extreme temperature ranges and long production lifecycles.

Supply support for LT4363MPMS-2#PBF 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

Analog Devices, Inc. is a global semiconductor leader specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision, power, and reliability-critical applications.

The LT4363 product line delivers high-voltage surge protection regulators designed specifically for mission-critical power systems in aerospace, industrial automation, and energy infrastructure where survivability under extreme electrical and thermal stress is non-negotiable.

FAQ

What distinguishes LT4363MPMS-2#PBF from other LT4363-2 variants?

The LT4363MPMS-2#PBF is the only LT4363-2 variant qualified for –55°C to +125°C operation (MP grade), with enhanced reliability screening per MIL-PRF-38535. It shares identical electrical functionality and MSOP-12 pinout with LT4363IMS-2#PBF and LT4363HMS-2#PBF but adds extended low-temperature startup, burn-in, and lot acceptance testing required for avionics and downhole tools.

Does LT4363MPMS-2#PBF support reverse battery protection?

Yes, LT4363MPMS-2#PBF supports reverse input protection: its VCC, SHDN, UV, and OV pins tolerate –60V, enabling use with back-to-back N-channel MOSFETs instead of lossy Schottky diodes. This configuration reduces forward voltage drop and power dissipation while maintaining full –55°C to 125°C operational integrity.

How does the fault timer in LT4363MPMS-2#PBF respond to overvoltage versus overcurrent events?

In overvoltage, the LT4363MPMS-2#PBF charges TMR with current scaling from ~4µA (V_DS ≤ 0.5V) to 50µA (V_DS = 75V); in overcurrent, it uses ~5× higher current (8–260µA). Both trigger FLT low at 1.275V and shut off GATE at 1.375V, but only overvoltage reduces timer current to 6µA during warning-overcurrent maintains full current for faster shutdown.

Can LT4363MPMS-2#PBF be used without the OV pin?

Yes, LT4363MPMS-2#PBF can operate with OV pin grounded. When OV is tied to GND, the overvoltage comparator is disabled and retry inhibition is inactive-allowing auto-restart after cool-down regardless of input voltage. This configuration matches LT4363-1 functional behavior except for the underlying LT4363-2 auto-restart logic.

What is the minimum TMR capacitor value required for stable operation of LT4363MPMS-2#PBF?

The LT4363MPMS-2#PBF requires a minimum 10nF capacitor on the TMR pin to ensure loop stability and accurate timing. Smaller values risk oscillation or premature fault triggering; larger values extend warning, shutdown, and restart intervals linearly-e.g., 1µF yields ~16.7ms warning and ~96.9ms total regulation time under typical overvoltage conditions.