Analog Devices Inc. LTC4380HMS-4#PBF

Overview

LTC4380HMS-4#PBF from Analog Devices is a high-temperature-rated, low-quiescent-current surge stopper IC that controls an external N-channel MOSFET to protect downstream loads from automotive load dump, reverse input, overvoltage (up to 72V input), and overcurrent faults. It features adjustable gate clamp voltage, 125°C operating ambient temperature, 8µA typical operating current, and auto-retry fault behavior. Used in 24V/28V vehicle power systems requiring robust transient protection.

For engineers reviewing the LTC4380HMS-4#PBF datasheet, LTC4380HMS-4#PBF pinout, LTC4380HMS-4#PBF application, or LTC4380HMS-4#PBF equivalent, key selection criteria include its –40°C to 125°C H-grade rating, MSOP-10 package, auto-retry (–4) fault response, externally adjustable gate clamp, and MOSFET stress-accelerated fault timing.

Technical Context

The LTC4380HMS-4#PBF implements a multiplier-based fault timer where TMR pin current scales with both V_DS (via DRN pin) and I_D (via SNS–OUT differential), enabling dynamic MOSFET safe operating area (SOA) enforcement. Its GATE driver delivers regulated 11.5V above OUT with internal 13.5V-above-VCC compliance limit - no fixed internal gate-to-GND clamp, requiring external Zener clamping on VCC for output voltage limiting.

It supports reverse input protection to –60V, uses an ON pin comparator for undervoltage detection (1.05V threshold) and shutdown control, and provides latchoff/retry selection via part number suffix (–4 = auto-retry). The FLT open-drain output signals fault status, and TMR capacitor sets both fault timeout and cool-down interval.

Key Specifications

Pinout & Package

Package: 10-Lead Plastic MSOP (3mm × 3mm footprint, 1.1mm height), RoHS-compliant, exposed pad (GND).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC4380IMS-4#PBF, the LTC4380HMS-4#PBF enables under-hood deployment; compared with LTC4380HDD-4#PBF, it offers easier hand-soldering and legacy MSOP compatibility but higher thermal resistance - critical for sustained 1A+ loads.

Availability

LTC4380HMS-4#PBF is available at Aetrix Electronics and suitable for automotive load dump protection, industrial 24V power supply hardening, and battery-powered telematics modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LTC4380HMS-4#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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving automotive, industrial, communications, and aerospace markets.

The LTC4380 product line delivers precision surge protection ICs designed specifically for high-reliability vehicle and industrial power systems, emphasizing ultra-low quiescent current, MOSFET stress-aware fault timing, and AEC-Q100 qualification.

FAQ

What is the maximum input voltage the LTC4380HMS-4#PBF can withstand?

The LTC4380HMS-4#PBF supports an input voltage range of 4V to 72V on the VCC pin. For inputs exceeding 72V (e.g., automotive load dump peaks), external clamping - such as a Zener diode from VCC to GND - is required to prevent damage. Absolute maximum VCC rating is 80V, and the device tolerates reverse input down to –60V without damage.

How does the LTC4380HMS-4#PBF implement adjustable output voltage clamping?

The LTC4380HMS-4#PBF has no internal gate-to-GND clamp (unlike –1/–2 versions). Instead, output clamping is set by placing a Zener diode between VCC and GND. Since GATE is regulated to VOUT + 11.5V and limited to VCC + 13.5V, the Zener voltage directly determines the maximum GATE voltage and thus the output clamp (e.g., 33V Zener → ~28V output limit). This enables precise, application-specific clamping.

What fault behavior does the LTC4380HMS-4#PBF provide, and how is it reset?

The LTC4380HMS-4#PBF implements auto-retry (–4 suffix) fault behavior: after TMR reaches 1.215V and shuts off the MOSFET, it enters a cool-down phase (TMR cycles between 1.215V and 3.4V), then automatically restarts when TMR discharges to 100mV. No manual reset or power cycle is needed - unlike latchoff versions (–1/–3) which require ON pin pulsing or power cycling.

Can the LTC4380HMS-4#PBF protect against reverse battery connection?

Yes. The LTC4380HMS-4#PBF tolerates –60V on the VCC pin with respect to GND, enabling direct reverse battery protection without external diodes or MOSFETs. When VCC is pulled negative, internal protection structures block conduction, and the device remains undamaged. This eliminates voltage drop and heat generation associated with Schottky or PMOS reverse-polarity solutions.

What is the role of the DRN pin in the LTC4380HMS-4#PBF, and how is it used?

The DRN pin senses the MOSFET's drain-to-source voltage (V_DS) by tracking the OUT node and sourcing current proportional to V_DS through an external resistor (R_DRN). This current, multiplied internally with SNS–OUT current, produces a TMR pin current proportional to MOSFET power dissipation - enabling adaptive fault timing that shortens timeout under high-stress conditions to enforce safe operating area (SOA) limits.