Analog Devices Inc. LTC3862HFE-2#TRPBF

Overview

LTC3862HFE-2#TRPBF from Analog Devices (formerly Linear Technology) is a high-temperature-rated, two-phase, constant-frequency current-mode boost/SEPIC DC/DC controller driving N-channel MOSFETs. It operates from 5.5V to 36V input, delivers up to 80V output, supports 75kHz–500kHz adjustable switching frequency, and features 10V INTVCC LDO with 4.4V UVLO rising threshold - enabling robust high-voltage power conversion in automotive and industrial systems.

For engineers reviewing the LTC3862HFE-2#TRPBF datasheet, LTC3862HFE-2#TRPBF pinout, LTC3862HFE-2#TRPBF application, or LTC3862HFE-2#TRPBF equivalent, key selection criteria include its H-grade (–40°C to +150°C) junction temperature rating, dual-channel phase control via PHASEMODE pin, programmable DMAX (75–96%), and 24-lead TSSOP package with exposed PGND pad for thermal management.

Technical Context

The LTC3862HFE-2#TRPBF implements fixed-frequency peak current mode control across two interleaved channels operating 180° out-of-phase, reducing input/output ripple and filter component stress. Its internal 10V INTVCC LDO powers gate drivers, while a cascaded 3.8V LDO supplies analog/digital circuitry - both thermally isolated and independently bypassed.

Phase synchronization is achieved via PLL-based SYNC input (50–650kHz), CLKOUT daisy-chaining, and PHASEMODE-selectable channel alignment (120°/180°). Slope compensation gain (0.625×–1.66×), leading edge blanking (210–375ns), and ±1% reference voltage ensure stable operation under wide duty cycle and load transients.

Key Specifications

Pinout & Package

Package: 24-lead plastic TSSOP (FE package), 0.65mm lead pitch, exposed PGND pad (Pin 25) requiring PCB soldering for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar boost/SEPIC controller applications.

Compared with LTC3862IFE-2#TRPBF, the LTC3862HFE-2#TRPBF adds 25°C higher junction temperature margin for sustained operation in harsh environments; versus LTC3862HUH-2#TRPBF, it trades slightly higher θJA for mature TSSOP assembly compatibility and lower PCB routing complexity.

Availability

LTC3862HFE-2#TRPBF is available at Aetrix Electronics and suitable for automotive LED drivers, industrial boost converters, telecom SEPIC supplies, and multi-phase high-power boost systems requiring stable component supply across extended temperature ranges.

Supply support for LTC3862HFE-2#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 acquired Linear Technology in 2017 and maintains full product support, documentation, and manufacturing continuity for all Linear power management ICs.

The LTC3862HFE-2#TRPBF belongs to Linear's PolyPhase® multi-phase controller family, designed specifically for high-efficiency, high-reliability DC/DC conversion in automotive, industrial, and telecom infrastructure where thermal resilience and precise current balancing are critical.

FAQ

What is the maximum operating junction temperature for the LTC3862HFE-2#TRPBF?

The LTC3862HFE-2#TRPBF is rated for –40°C to +150°C junction temperature (H-grade). This specification is guaranteed across the full range, with thermal shutdown protection engaging above TJMAX = 150°C. The 24-lead TSSOP package has θJA = 38°C/W, so proper PCB copper area and exposed pad soldering are essential to sustain this rating under full load.

How does the DMAX pin affect duty cycle limiting in the LTC3862HFE-2#TRPBF?

The DMAX pin on the LTC3862HFE-2#TRPBF sets the maximum duty cycle in three discrete states: 96% (connected to SGND), 84% (left floating), or 75% (connected to 3V8). This limit is derived from an internal 12× clock for precision, making it highly accurate and independent of external component tolerances - critical for stable high-step-up operation in the LTC3862HFE-2#TRPBF.

Can the LTC3862HFE-2#TRPBF be used in SEPIC topology, and what design considerations apply?

Yes, the LTC3862HFE-2#TRPBF supports SEPIC operation using its dual-channel current-mode architecture. Designers must configure both channels with coupled inductors or separate windings, ensure matched sense resistors, and verify slope compensation for stability at low duty cycles. The LTC3862HFE-2#TRPBF's programmable blanking and wide frequency range simplify SEPIC loop compensation.

What is the purpose of the 3V8 pin on the LTC3862HFE-2#TRPBF, and how should it be decoupled?

The 3V8 pin on the LTC3862HFE-2#TRPBF is the output of an internal 3.8V LDO powered from INTVCC, supplying analog and digital control circuitry. It must be decoupled with a 1nF X5R ceramic capacitor placed directly between 3V8 and SGND, as close as possible to the pin. This LDO is not intended for external loads - doing so risks regulation loss and instability in the LTC3862HFE-2#TRPBF's internal loops.

How does the PHASEMODE pin configure multi-phase operation in the LTC3862HFE-2#TRPBF?

The PHASEMODE pin on the LTC3862HFE-2#TRPBF selects interleaving phase relationships: grounded → 180° CH1–CH2, floating → 180° CH1–CH2, tied to 3V8 → 120° CH1–CH2. It also defines CH1–CLKOUT alignment (90°/60°/240°), enabling seamless expansion to 3-, 4-, 6-, or 12-phase systems using multiple LTC3862HFE-2#TRPBF devices without external timing components.