Analog Devices Inc. LTC4366HTS8-1#TRPBF

Overview

LTC4366HTS8-1#TRPBF from Analog Devices is a high-voltage surge stopper IC that protects downstream loads by regulating output voltage during overvoltage transients using an external N-channel MOSFET. It features adjustable overvoltage clamping (via FB divider), 9-second internal cool-down timer, latch-off fault behavior (–1 version), and operates across –40°C to 125°C. It enables rugged floating topologies in 28V vehicle systems and high-voltage DC distribution.

For engineers reviewing the LTC4366HTS8-1#TRPBF datasheet, LTC4366HTS8-1#TRPBF pinout, LTC4366HTS8-1#TRPBF application, or LTC4366HTS8-1#TRPBF equivalent, this device delivers precise overvoltage regulation at up to 43V with thermal-safe MOSFET control, shutdown IQ < 14µA, and TSOT-23 package compatibility for space-constrained industrial and automotive surge protection designs.

Technical Context

The LTC4366HTS8-1#TRPBF implements a floating architecture where its OUT and BASE pins are powered from the MOSFET source, enabling operation with input voltages exceeding 500V. Its overvoltage regulation amplifier compares FB voltage to a 1.23V reference referenced to OUT, enabling accurate clamp setting independent of absolute supply level.

It uses dual shunt regulators (12V on VDD, 5.7V on OUT) and a charge pump to drive the external MOSFET gate 12V above source. The TIMER pin controls overvoltage duration via external capacitor, while the SD pin provides <14µA shutdown mode with fault-clearing capability - critical for latched-off recovery in safety-critical systems.

Key Specifications

Pinout & Package

Package: 8-Lead Plastic TSOT-23 (0.65mm pitch), exposed pad optional for thermal relief. Pin 1 = VDD, Pin 8 = GATE; pinout matches standard TSOT-23 orientation per Analog Devices datasheet Rev. F.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC4366HTS8-2#TRPBF, the LTC4366HTS8-1#TRPBF provides deterministic fault holdover for safety validation, while TPS26631RHFR trades configurability for integration and reduced component count - making each optimal for distinct reliability vs. simplicity trade-offs.

Availability

LTC4366HTS8-1#TRPBF is available at Aetrix Electronics and suitable for 28V vehicle systems, avionic DC bus protection, and industrial high-voltage DC distribution requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LTC4366HTS8-1#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. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and aerospace markets.

The LTC4366 product line was designed specifically for high-reliability overvoltage protection in harsh environments, emphasizing floating operation, thermal-safe MOSFET control, and latch-off fault behavior for mission-critical power systems.

FAQ

What is the key functional difference between LTC4366HTS8-1#TRPBF and LTC4366HTS8-2#TRPBF?

The LTC4366HTS8-1#TRPBF enters a latched-off state after an overvoltage fault and remains off until the SD pin is toggled; the LTC4366HTS8-2#TRPBF automatically retries after a fixed 9-second cool-down period. Both share identical electrical specs, pinout, and temperature rating (–40°C to 125°C), but their fault recovery behavior is fundamentally different - making the –1 version mandatory for fail-safe system architectures.

How does the LTC4366HTS8-1#TRPBF achieve operation with input voltages exceeding 500V?

The LTC4366HTS8-1#TRPBF achieves ultra-high input voltage tolerance by powering its internal circuitry from the MOSFET source (via OUT and BASE pins), not the input rail. This floating architecture isolates sensitive regulation blocks from input surge - only the external MOSFET and resistors (RIN, RSS) must withstand full transient voltage, while the LTC4366HTS8-1#TRPBF itself sees only clamped rails (12V on VDD, 5.7V on OUT).

What is the role of the TIMER pin on the LTC4366HTS8-1#TRPBF, and how is it configured?

The TIMER pin on the LTC4366HTS8-1#TRPBF sets the maximum allowable overvoltage regulation duration before fault latching. It is charged at 9µA; when voltage reaches 2.8V, the part shuts off the MOSFET and initiates the 9-second cool-down. A capacitor from TIMER to VSS configures timing: CT (nF) = 3.2 × t (ms). Leaving TIMER open yields ~1µs regulation - suitable for very fast clamping.

Can the LTC4366HTS8-1#TRPBF be used without an external PNP transistor on the BASE pin?

Yes - the BASE pin may be tied directly to VSS if external PNP shunt regulation is not needed. The internal 6.2V Zener between BASE and OUT remains active, but the PNP option is only required when RSS power dissipation must be minimized in high-voltage applications. Using the PNP reduces required RSS value by up to 35× (based on minimum Beta), lowering resistor size and thermal stress.

What are the absolute maximum ratings for GATE-to-OUT voltage on the LTC4366HTS8-1#TRPBF?

The absolute maximum GATE-to-OUT voltage for the LTC4366HTS8-1#TRPBF is 10V, per the Absolute Maximum Ratings table. The internal clamp limits GATE to 12V above VSS, but GATE–OUT must not exceed 10V to avoid damage. This constraint governs selection of external MOSFETs and gate drive loop stability - especially during fast discharge events where GATE is pulled toward OUT with 200mA sink capability.