Analog Devices Inc. LTC4364IS-1#PBF

Overview

LTC4364IS-1#PBF from Analog Devices is a surge stopper with ideal diode controller for automotive and industrial power rail protection. It regulates output voltage to 27V during 92V/1ms transients, provides reverse input protection to –40V, and latches off the external N-channel MOSFET pass device upon overvoltage or overcurrent fault timeout. Used in automotive load-dump protection circuits where continuous operation during transients is critical.

For engineers reviewing the LTC4364IS-1#PBF datasheet, LTC4364IS-1#PBF pinout, LTC4364IS-1#PBF application, or LTC4364IS-1#PBF equivalent, key selection factors include latch-off fault behavior, 4V–80V operating range, 1.25V FB reference accuracy, 10μA shutdown current, and SO-16 package compatibility with AEC-Q100 Grade I (–40°C to +85°C) requirements.

Technical Context

The LTC4364IS-1#PBF implements dual-control architecture: a voltage-regulating surge stopper (HGATE) for overvoltage clamping and an ideal diode controller (DGATE) for reverse polarity protection and output holdup. Its fault timer uses a single external capacitor to set warning (1.25V), turn-off (1.35V), and cool-down thresholds - with latched-off behavior post-fault unique to the -1 variant.

It features independent UV/OV comparators (1.25V threshold, 25–80mV hysteresis), precise 50mV/25mV current-sense thresholds, and gate drivers with internal 12V clamp above SOURCE. The SO-16 package supports high-voltage clearance and thermal performance up to 125°C junction temperature.

Key Specifications

Pinout & Package

Package: 16-Lead Plastic SO (Small Outline), 0.300" wide body, exposed pad optional, θ_JA = 100°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar surge protection and ideal diode control applications.

Compared with LTC4365IS-1#PBF, the LTC4364IS-1#PBF offers tighter 4V–80V range and requires external V_CC clamping above 80V, but maintains identical latch-off timing and SO-16 footprint. Compared with TPS26631PWPR, it delivers dual-function control (surge + ideal diode) with AEC-Q100 qualification and adjustable clamping, at the cost of external MOSFETs.

Availability

LTC4364IS-1#PBF is available at Aetrix Electronics and suitable for automotive ECU protection, industrial redundant power ORing, and avionics input port hardening requiring stable component supply and long-term lifecycle support.

Supply support for LTC4364IS-1#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, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The LTC4364IS-1#PBF belongs to the Surge Stopper family designed specifically for high-reliability power rail protection in automotive and aerospace applications, emphasizing latch-off safety, reverse polarity resilience, and precise transient regulation.

FAQ

What is the key functional difference between LTC4364IS-1#PBF and LTC4364IS-2#PBF?

The LTC4364IS-1#PBF implements latch-off fault behavior: once the TMR pin reaches 1.35V during overvoltage or overcurrent, HGATE remains low until manually reset via SHDN or UV pin. In contrast, the LTC4364IS-2#PBF automatically restarts after a 32-cycle cool-down timer, provided the OV pin falls below its 1.25V threshold. This makes the -1 variant suitable for safety-critical systems requiring explicit operator or system intervention before recovery.

Can LTC4364IS-1#PBF be used with 48V input systems?

Yes - the LTC4364IS-1#PBF operates from 4V to 80V, making it fully compatible with 48V nominal systems. For inputs exceeding 80V, an external clamp (e.g., 82V Zener from VCC to GND) is required per the datasheet's "Withstands Surges Over 80V with VCC Clamp" specification. Its 1.25V FB reference and adjustable divider allow precise output clamping at system-appropriate levels such as 54V or 58V.

How does the ideal diode function of LTC4364IS-1#PBF improve system efficiency?

The LTC4364IS-1#PBF drives the DGATE pin to regulate the forward voltage drop (V_SD) across the external N-MOSFET to ~30mV, far lower than the 300–500mV drop of a Schottky diode. This reduces conduction loss by >80% at 5A, directly improving thermal performance and usable supply voltage at the load - especially critical in 12V/24V systems with tight voltage margins.

What is the minimum external capacitor value required on the TMR pin for reliable fault timing?

The TMR pin requires a capacitor with low voltage and temperature coefficients; 6.8µF is used in the典型 application (TA01b) for 50ms fault timeout. Smaller values reduce timing - e.g., 1µF yields ~7ms timeout. Capacitor tolerance and drift directly affect timing accuracy; X7R or C0G dielectrics are recommended. The datasheet specifies that timing scales linearly with capacitance, and the TMR current increases with V_CC–V_OUT, ensuring shorter timeouts during higher-energy faults.

Is LTC4364IS-1#PBF pin-compatible with other package variants like LTC4364IMS-1#PBF?

No - the LTC4364IS-1#PBF uses a 16-lead SO package with specific pinout (e.g., NC on Pins 3 and 7), while the LTC4364IMS-1#PBF uses a 16-lead MSOP with different pin assignments (e.g., NC on Pins 3 and 7, but shifted physical positions). Although both share identical electrical functionality and logic, PCB layout and footprint are not interchangeable. Migration requires board redesign and validation per JEDEC MO-178 (SO) vs. MO-187 (MSOP) standards.