Analog Devices Inc. LTC4380CMS-1#TRPBF

Overview

LTC4380CMS-1#TRPBF from Analog Devices is a 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 250Vpk), and overcurrent events. It features fixed 31.5V/50V gate clamp selection via SEL pin, 8µA operating current, 4V–72V input range, and latchoff fault behavior. Used in 12V automotive power rails requiring robust transient immunity.

For engineers reviewing the LTC4380CMS-1#TRPBF datasheet, LTC4380CMS-1#TRPBF pinout, LTC4380CMS-1#TRPBF application, or LTC4380CMS-1#TRPBF equivalent, key selection criteria include gate clamp voltage configuration (SEL = GND → 31.5V), latchoff vs auto-retry behavior, MOSFET stress acceleration via TMR-based multiplier, reverse input protection to –60V, and AEC-Q100 qualification for automotive use.

Technical Context

The LTC4380CMS-1#TRPBF 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) protection. Its internal 20µA charge pump regulates GATE to V_OUT + 11.5V during normal operation, while clamping GATE to 31.5V (SEL = GND) or 50V (SEL = V_CC) during overvoltage.

It integrates undervoltage detection on the ON pin (1.05V threshold, 45mV hysteresis), open-drain FLT output signaling fault status, and supports back-to-back MOSFET configurations for reverse polarity protection. The device latches off after fault timeout and requires ON pin pulse (<100µs low) or power cycle for reset - distinguishing it from auto-retry variants like LTC4380-2.

Key Specifications

Pinout & Package

10-Lead Plastic MSOP package (3mm × 3mm footprint, 0.5mm pitch); exposed pad optional for thermal enhancement and GND connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC4380CMS-1#TRPBF, the IMS-1 variant extends thermal capability for harsher environments without changing interface or protection profile, while the CMS-2 variant replaces latchoff with auto-retry - altering system-level fault response strategy and eliminating need for external reset logic.

Availability

LTC4380CMS-1#TRPBF is available at Aetrix Electronics and suitable for automotive infotainment, industrial PLCs, battery-powered telematics, and high-reliability always-on systems requiring stable component supply and long-term obsolescence management.

Supply support for LTC4380CMS-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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The LTC4380 family was designed specifically for robust, low-quiescent-power surge protection in automotive and industrial power distribution - emphasizing latchoff safety, MOSFET stress awareness, and reverse-input resilience without external diodes.

FAQ

What is the gate clamp voltage configuration for LTC4380CMS-1#TRPBF?

The LTC4380CMS-1#TRPBF has fixed internal gate clamp voltages: 31.5V when the SEL pin is tied to GND, or 50V when SEL is tied to V_CC/OUT. This version does not support adjustable clamping. The 31.5V setting limits output to ~27V in 12V systems, making it ideal for automotive load dump protection. The LTC4380CMS-1#TRPBF datasheet confirms this behavior in Table 1 and the PIN FUNCTIONS section.

Does LTC4380CMS-1#TRPBF support auto-retry or latchoff fault behavior?

LTC4380CMS-1#TRPBF implements latchoff fault behavior: once the TMR pin reaches 1.215V due to overvoltage or overcurrent, the MOSFET turns off and remains latched until the ON pin is pulled low for >100µs or power is cycled. This differs from auto-retry versions (e.g., LTC4380-2), which cool down and restart automatically. The latchoff mode is confirmed in the OPERATION section and Table 1 of the LTC4380CMS-1#TRPBF datasheet.

Can LTC4380CMS-1#TRPBF be used for reverse input protection without a Schottky diode?

Yes - the LTC4380CMS-1#TRPBF supports back-to-back N-channel MOSFET configurations by driving both gates, enabling true reverse polarity protection down to –60V without Schottky diode forward voltage drop or thermal loss. This is explicitly stated in the FEATURES and PIN FUNCTIONS sections, and the GATE pin's ability to drive bidirectional configurations is validated in the BLOCK DIAGRAM and APPLICATIONS INFORMATION.

What is the minimum recommended TMR capacitor value for LTC4380CMS-1#TRPBF?

The LTC4380CMS-1#TRPBF datasheet does not specify a minimum TMR capacitor value, but recommends a 10V-rated X7R ceramic capacitor for stability across temperature and voltage. Typical designs use ≥1µF (e.g., 8.2µF in Figure 1) to ensure sufficient fault timing margin. Smaller values reduce fault timeout and cool-down duration; however, values below 100nF may cause premature tripping under light stress. Designers should verify timing using the TMR current equations in the ELECTRICAL CHARACTERISTICS table.

Is LTC4380CMS-1#TRPBF AEC-Q100 qualified?

No - LTC4380CMS-1#TRPBF is a commercial-grade (0°C to 70°C) MSOP variant and is not AEC-Q100 qualified. Automotive-grade versions carry the #W suffix (e.g., LTC4380IMS-1#WTRPBF) and are explicitly listed in the ORDER INFORMATION table as "AUTOMOTIVE PRODUCTS". The LTC4380CMS-1#TRPBF datasheet states that only models designated with #W are approved for automotive use, and reliability reports are provided separately for those parts.