Analog Devices Inc. LT4363CS-2#TRPBF

Overview

LT4363CS-2#TRPBF from Analog Devices is a high-voltage surge stopper IC that controls an external N-channel MOSFET to regulate output voltage during transients up to 100V, limits current via 50mV SNS–OUT sense threshold, and features auto-retry fault recovery with adjustable timer. It operates from 4V to 80V input, supports reverse input protection to –60V, and delivers 12V regulated output in typical hot-swap applications.

For engineers reviewing the LT4363CS-2#TRPBF datasheet, LT4363CS-2#TRPBF pinout, LT4363CS-2#TRPBF application, or LT4363CS-2#TRPBF equivalent, key selection criteria include its 16-pin SO package, LT4363-2 auto-restart behavior, 1.275V FB reference, 0.5V TMR retry threshold, and UV/OV comparator support - all critical for avionic surge protection and battery-powered high-side switch designs.

Technical Context

The LT4363CS-2#TRPBF implements dual-fault protection: overvoltage regulation via feedback-controlled GATE drive (FB = 1.275V) and overcurrent limiting via SNS–OUT differential sensing (ΔVSNS = 50mV nominal). Its fault timer uses VCC–OUT voltage-dependent current sourcing to dynamically scale timing against MOSFET SOA constraints.

Unlike the latch-off LT4363-1, the LT4363-2 variant integrates cool-down and auto-restart logic: after TMR discharges to 0.5V, GATE re-enables without external reset; OV pin monitoring (1.275V threshold) blocks retry during sustained overvoltage, preventing motorboating.

Key Specifications

Pinout & Package

LT4363CS-2#TRPBF is housed in a 16-lead plastic SO package (S package), with exposed thermal pad not present (unlike DFN variants). Pin 1 is OUT; pin 16 is GND. The SO package offers 80°C/W junction-to-ambient thermal resistance and supports standard reflow or wave soldering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC4365IMS-2#TRPBF and TPS26631PWPR, LT4363CS-2#TRPBF offers superior flexibility: adjustable output clamp via FB, full –60V reverse tolerance, VDS-adaptive fault timing, and independent UV/OV control - making it uniquely suited for high-reliability, wide-input industrial and aerospace systems.

Availability

LT4363CS-2#TRPBF is available at Aetrix Electronics and suitable for avionic surge protection, hot-swap board insertion, and battery-powered high-side switch applications requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for LT4363CS-2#TRPBF 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 (now part of Analog Devices, Inc. following merger with Linear Technology) is a global leader in high-performance analog, mixed-signal, and power management semiconductors.

The LT4363 product line was designed specifically for high-voltage transient protection in demanding environments such as aerospace, industrial control, and automotive - delivering reliable, adaptive fault management without external microcontroller intervention.

FAQ

What is the key functional difference between LT4363CS-2#TRPBF and LT4363CS-1#TRPBF?

The LT4363CS-2#TRPBF implements auto-restart fault recovery: after a fault condition clears and the TMR capacitor discharges to 0.5V, the GATE pin automatically re-enables the external MOSFET. In contrast, the LT4363CS-1#TRPBF latches off permanently and requires a SHDN pin reset pulse (≥100µs low) to resume operation. This makes LT4363CS-2#TRPBF ideal for unattended or remote systems where manual intervention is impractical.

How does the LT4363CS-2#TRPBF achieve adaptive fault timing based on MOSFET stress?

The LT4363CS-2#TRPBF measures VCC–OUT voltage to infer MOSFET drain-source voltage (VDS) and scales the TMR capacitor charging current accordingly - from ~4µA at low VDS to 50µA at 75V VDS during overvoltage. This ensures shorter fault timers under high-stress conditions, keeping the MOSFET within its Safe Operating Area (SOA) without requiring fixed timing components or external compensation.

Can the LT4363CS-2#TRPBF be used with a P-channel MOSFET instead of an N-channel device?

No - the LT4363CS-2#TRPBF is designed exclusively for N-channel MOSFETs configured as high-side switches. Its GATE driver is optimized to pull up relative to the OUT pin (source), and its current sense architecture assumes SNS referenced to the source terminal. Using a P-channel device would violate the internal amplifier topology and render UV/OV, FB, and SNS functionality inoperable.

What is the minimum TMR capacitor value required for stable operation of LT4363CS-2#TRPBF?

A minimum 10nF capacitor is required between TMR and GND to ensure loop stability and prevent oscillation during regulation. Smaller values may cause erratic fault timing or false triggering. For typical 100ms–1s fault windows, 100nF to 1µF ceramic capacitors are commonly used, selected based on desired warning and cool-down durations per the datasheet timing equations.

Does the LT4363CS-2#TRPBF support reverse polarity protection without additional components?

The LT4363CS-2#TRPBF itself does not provide reverse polarity protection, but it enables robust implementation using back-to-back N-channel MOSFETs - eliminating the voltage drop and power loss of Schottky diodes. Its VCC and SHDN pins tolerate –60V, and the UV/OV comparators can be configured to disable the MOSFETs during reverse connection, making it a core enabler of efficient, bidirectional protection schemes.