Analog Devices Inc. LT4363IDE-1#TRPBF

Overview

LT4363IDE-1#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, provides adjustable 27V overvoltage clamping, delivers fast 1µs overcurrent fault response (t_OFF(OC) ≤ 2.5µs), and supports –40°C to 85°C operation in a 12-lead 4mm × 3mm DFN package - used in avionic power rails and industrial hot-swap systems.

For engineers reviewing the LT4363IDE-1#TRPBF datasheet, LT4363IDE-1#TRPBF pinout, LT4363IDE-1#TRPBF application, or LT4363IDE-1#TRPBF equivalent, this page delivers verified specifications including 50mV current sense threshold, 1.275V FB reference, 1.275V TMR fault threshold, 7µA shutdown current, and latch-off behavior (LT4363-1 variant) - critical for surge-tolerant system design and MOSFET SOA protection.

Technical Context

The LT4363IDE-1#TRPBF implements dual-fault protection via independent voltage and current regulation loops: an internal amplifier maintains 1.275V at FB during overvoltage by modulating GATE to limit V_OUT, while a precision current sense circuit holds ΔV_SNS–OUT at 50mV (or 25mV if V_OUT < 2V) during overcurrent. Fault timing is dynamically scaled by V_CC–V_OUT to match MOSFET safe operating area constraints.

It features a programmable fault timer with three phases - early warning (FLT low at 1.275V), shutdown (GATE off at 1.375V), and cool-down (TMR discharge to 0.5V) - and includes UV/OV comparators (1.275V thresholds), reverse input protection to –60V, and SHDN pin tolerance from –60V to 100V. The LT4363-1 variant latches off permanently until reset; no auto-retry occurs.

Key Specifications

Pinout & Package

LT4363IDE-1#TRPBF is housed in a 12-lead (4mm × 3mm) plastic DFN package with exposed thermal pad (Pin 13, connected to GND). Pin functions are electrically validated per Analog Devices' Rev. C datasheet and confirmed for the DE package variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC4365IMS-2#TRPBF and TPS26631PWPR, LT4363IDE-1#TRPBF offers wider 4V–80V operation, external MOSFET flexibility for high-current designs, precise 1.275V references, and mandatory latch-off behavior - making it uniquely suitable for mission-critical avionics and intrinsic safety systems where uncontrolled restart is prohibited.

Availability

LT4363IDE-1#TRPBF is available at Aetrix Electronics and suitable for avionic power protection, industrial hot-swap modules, and intrinsic safety barriers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LT4363IDE-1#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, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and aerospace markets.

The LT4363IDE-1#TRPBF belongs to Analog Devices' Surge Stopper family, engineered specifically for high-reliability power system protection in harsh environments where transient immunity, precise fault timing, and latch-off behavior are mandatory.

FAQ

What is the key functional difference between LT4363IDE-1#TRPBF and LT4363IDE-2#TRPBF?

The LT4363IDE-1#TRPBF implements latch-off behavior: once the fault timer reaches 1.375V and turns off the GATE, it remains off indefinitely until the SHDN pin is pulsed low for ≥100µs. In contrast, LT4363IDE-2#TRPBF automatically retries after cool-down (TMR discharges to 0.5V), making LT4363IDE-1#TRPBF preferred for safety-critical applications where uncontrolled restart is unacceptable.

Can LT4363IDE-1#TRPBF be used with a P-channel MOSFET instead of an N-channel device?

No - LT4363IDE-1#TRPBF is designed exclusively for N-channel MOSFETs configured as high-side switches. Its GATE driver is a charge pump that sources voltage relative to the OUT pin (source), enabling full enhancement of N-MOSFETs. Driving a P-MOSFET would require inverted logic and gate drive referenced to V_CC, which the LT4363IDE-1#TRPBF does not support.

How is the overvoltage clamp voltage set for LT4363IDE-1#TRPBF?

The overvoltage clamp voltage is set by connecting a resistive divider between the OUT and GND pins, with the midpoint fed to the FB pin. Since the LT4363IDE-1#TRPBF regulates FB to 1.275V, the output clamp equals 1.275V × (1 + R1/R2), where R1 is the upper resistor (OUT–FB) and R2 is the lower resistor (FB–GND). A typical 27V clamp uses R1 = 127kΩ and R2 = 4.99kΩ.

What is the minimum TMR capacitor value required for stable operation of LT4363IDE-1#TRPBF?

The datasheet specifies a minimum 10nF capacitor on the TMR pin to ensure loop stability and proper fault timing. Using less than 10nF may cause erratic FLT assertion, incomplete cool-down, or failure to reach the 0.5V retry threshold (for LT4363-2) or reliable latch-off reset (for LT4363-1). Larger values extend warning and shutdown delays linearly.

Does LT4363IDE-1#TRPBF provide reverse polarity protection out-of-the-box?

LT4363IDE-1#TRPBF itself does not block reverse current, but its pins (VCC, SHDN, UV, OV) tolerate –60V, enabling implementation of reverse input protection using two back-to-back N-channel MOSFETs - eliminating forward voltage drop and power loss versus Schottky diodes. External FETs and gate drive coordination are required.