Analog Devices Inc. LTC4366MPDDB-1#TRMPBF

Overview

LTC4366MPDDB-1#TRMPBF from Analog Devices is a high-voltage surge stopper IC that protects downstream loads by regulating output voltage during overvoltage transients up to >500V 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 –55°C to +125°C in an 8-lead 3mm × 2mm DFN package. It is used in 28V vehicle systems requiring uninterrupted operation during transient surges.

For engineers reviewing the LTC4366MPDDB-1#TRMPBF datasheet, LTC4366MPDDB-1#TRMPBF pinout, LTC4366MPDDB-1#TRMPBF application, or LTC4366MPDDB-1#TRMPBF equivalent, this page delivers verified specifications, thermal-latched fault behavior, DFN package layout guidance, and design-critical timing parameters for rugged floating topologies in avionic and industrial DC distribution.

Technical Context

The LTC4366MPDDB-1#TRMPBF implements a floating architecture where VDD and OUT are independently shunt-regulated (12V and 5.7V respectively), enabling operation with input voltages exceeding 500V. Its overvoltage regulation amplifier compares FB to a 1.23V reference below OUT, driving GATE to clamp output at user-defined voltage via RFB1/RFB2 ratio.

Fault management uses dual timers: a user-configurable overvoltage regulation timer (via TIMER pin capacitor) and a fixed 9-second internal cool-down period after fault latching. Unlike the auto-retry –2 variant, the –1 version remains latched off until SD is toggled - critical for safety-critical systems requiring explicit reset confirmation.

Key Specifications

Pinout & Package

Package: 8-lead (3mm × 2mm) plastic DFN with optional exposed pad connected to VSS. Thermal resistance θJA = 75°C/W when VSS pad is soldered to PCB.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC4366HDDB-1#TRMPBF, the LTC4366MPDDB-1#TRMPBF provides guaranteed operation down to –55°C - essential for aerospace cold-start scenarios - while LTC4366MPDDB-2#TRMPBF trades explicit reset control for autonomous recovery, making the –1 variant the sole choice for MIL-STD-461/DO-160-compliant latched-fault architectures.

Availability

LTC4366MPDDB-1#TRMPBF is available at Aetrix Electronics and suitable for avionic power distribution, military vehicle electrical systems, and industrial high-voltage DC bus protection requiring stable component supply across extreme temperature ranges and long production lifecycles.

Supply support for LTC4366MPDDB-1#TRMPBF 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 semiconductor leader specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision, power, and reliability-critical applications.

The LTC4366 product line delivers high-voltage surge protection ICs designed specifically for floating, wide-input-range DC power systems in aerospace, defense, and industrial environments where latch-off fault behavior and extended temperature operation are mandatory.

FAQ

What is the key functional difference between LTC4366MPDDB-1#TRMPBF and LTC4366MPDDB-2#TRMPBF?

The LTC4366MPDDB-1#TRMPBF features latch-off fault behavior: once an overvoltage event triggers shutdown, it remains off until the SD pin is actively toggled. In contrast, the LTC4366MPDDB-2#TRMPBF automatically retries after a fixed 9-second cool-down period. This makes the –1 version mandatory for safety-critical systems requiring explicit operator or controller intervention before resuming operation.

Does LTC4366MPDDB-1#TRMPBF support input voltages above 500V?

Yes - the LTC4366MPDDB-1#TRMPBF supports input voltages exceeding 500V due to its floating architecture: VDD and OUT pins are independently shunt-regulated (12V and 5.7V), isolating internal circuitry from the full input potential. The upper limit depends only on external MOSFET voltage rating and resistor power handling, not the IC's absolute maximum ratings.

What is the purpose of the BASE pin on LTC4366MPDDB-1#TRMPBF?

The BASE pin on LTC4366MPDDB-1#TRMPBF drives the base of an external PNP transistor to replace the high-power RSS resistor. It sources ~0.8µA and references a 6.1V Zener (OUT–BASE), enabling lower-power, physically smaller resistor selection while maintaining shunt regulation - especially valuable in space-constrained avionic designs.

How is overvoltage clamp voltage set for LTC4366MPDDB-1#TRMPBF?

The overvoltage clamp voltage for LTC4366MPDDB-1#TRMPBF is set by an external resistive divider (RFB1/RFB2) from OUT to ground, connected to the FB pin. The regulation amplifier holds FB = OUT – 1.23V, so V_CLAMP = 1.23V × (1 + RFB2/RFB1). For example, RFB1 = 12.4kΩ and RFB2 = 422kΩ yields a 43V clamp - confirmed in the typical application schematic.

Is the exposed pad on LTC4366MPDDB-1#TRMPBF required to be connected to VSS?

No - the exposed pad on LTC4366MPDDB-1#TRMPBF is optional per the datasheet. It may be left unconnected or soldered to VSS. However, connecting it to VSS reduces θJA from 135°C/W to 75°C/W (when soldered), significantly improving thermal performance during sustained overvoltage regulation - strongly recommended for high-power applications.