Analog Devices Inc. LTC4380HDD-3#PBF

Overview

LTC4380HDD-3#PBF from Analog Devices is a low-quiescent-current (11 µA typ) surge stopper IC that controls an external N-channel MOSFET to protect downstream loads from automotive load dump, reverse input (-60 V), overvoltage (up to 72 V input), and overcurrent events. It features adjustable gate clamp voltage, MOSFET stress-accelerated fault timing, and latchoff behavior for robust industrial and automotive power rail protection.

For engineers reviewing the LTC4380HDD-3#PBF datasheet, LTC4380HDD-3#PBF pinout, LTC4380HDD-3#PBF application, or LTC4380HDD-3#PBF equivalent, key selection considerations include its –40°C to 125°C H-grade temperature range, 10-pin 3 mm × 3 mm DFN package, adjustable gate clamp architecture (no internal 31.5 V/50 V clamp), latchoff fault response, and 4 V to 72 V operating input range with 6 µA shutdown current.

Technical Context

The LTC4380HDD-3#PBF implements a multiplier-based fault timer where TMR pin current scales with both MOSFET V_DS (sensed at DRN) and I_D (via ΔV_SNS), enabling dynamic SOA protection. Its GATE driver regulates to V_OUT + 11.5 V and lacks internal gate-to-GND clamps-gate voltage is limited only by V_CC + 13.5 V compliance and external Zener clamping at V_CC.

It uses an accurate ON pin comparator (1.05 V threshold, 45 mV hysteresis) for undervoltage detection and shutdown control, reducing quiescent current to 6 µA. The device latches off upon fault (TMR = 1.215 V) and requires ON pin pulse (<100 µs low) or power cycle for reset-no auto-retry behavior.

Key Specifications

Pinout & Package

Package: 10-lead (3 mm × 3 mm) plastic DFN with exposed thermal pad (Pin 11 = GND, optional PCB connection).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC4380HDD-1#PBF, the LTC4380HDD-3#PBF trades fixed clamping simplicity for full external adjustability and deterministic latchoff, while LTC4380HDD-4#PBF replaces latchoff with auto-retry-making LTC4380HDD-3#PBF optimal for safety-critical or manually managed systems requiring guaranteed fault isolation.

Availability

LTC4380HDD-3#PBF is available at Aetrix Electronics and suitable for automotive load dump protection, industrial power rail hardening, and battery-powered always-on systems requiring stable component supply across extended temperature and long lifecycle requirements.

Supply support for LTC4380HDD-3#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 precision instrumentation, industrial automation, and automotive markets.

The LTC4380 family is designed specifically for ruggedized power path protection in automotive and industrial environments-delivering ultra-low quiescent current, MOSFET SOA-aware fault timing, and flexible clamping architectures.

FAQ

What is the gate clamp architecture of the LTC4380HDD-3#PBF?

The LTC4380HDD-3#PBF has no internal gate-to-GND clamp. Its GATE pin is regulated to V_OUT + 11.5 V and limited only by V_CC + 13.5 V compliance. Output clamping is achieved by externally clamping the V_CC pin with a Zener diode-enabling precise, adjustable clamp voltages from 18 V to 86 V. This architecture is confirmed in the LTC4380 datasheet Rev. C, Pin Functions and Operation sections.

Does the LTC4380HDD-3#PBF support auto-retry after a fault?

No. The LTC4380HDD-3#PBF implements latchoff behavior: once the TMR pin reaches 1.215 V during overvoltage or overcurrent, the MOSFET turns off and remains off until the ON pin is pulsed low for ≥100 µs or power is cycled. This differs from LTC4380-2/-4 variants, which feature auto-retry with cool-down timing. The latchoff behavior is explicitly defined in Table 1 and the OPERATION section of the LTC4380 datasheet Rev. C.

What is the maximum input voltage rating for the LTC4380HDD-3#PBF?

The LTC4380HDD-3#PBF supports an operating input voltage range of 4 V to 72 V on the VCC pin. Absolute maximum rating is 80 V, but sustained operation above 72 V requires external clamping (e.g., Zener diode) to prevent exceeding the GATE pin's V_CC + 13.5 V limit. This 72 V upper bound is specified in the ELECTRICAL CHARACTERISTICS table (Note 6) and ORDER INFORMATION tables of the LTC4380 datasheet Rev. C.

How does the fault timer in the LTC4380HDD-3#PBF respond to MOSFET stress?

The LTC4380HDD-3#PBF fault timer uses an internal multiplier that generates TMR pin current proportional to both MOSFET V_DS (sensed at DRN) and I_D (via ΔV_SNS). Higher power dissipation accelerates TMR charging-shortening fault timeout to keep the MOSFET within its safe operating area. This dynamic timing is detailed in the PIN FUNCTIONS (DRN, TMR) and OPERATION sections of the LTC4380 datasheet Rev. C.

What package and thermal characteristics does the LTC4380HDD-3#PBF have?

The LTC4380HDD-3#PBF uses a 10-lead 3 mm × 3 mm plastic DFN (DD) package with exposed thermal pad (Pin 11 = GND). Its maximum junction temperature is 135°C, and thermal resistance θ_JA is 43°C/W. The exposed pad is optional for PCB connection but strongly recommended for thermal performance in high-current applications. These specifications are documented in the ABSOLUTE MAXIMUM RATINGS and PIN CONFIGURATION sections of the LTC4380 datasheet Rev. C.