Analog Devices Inc. LTC3862EFE-1#TRPBF

Overview

LTC3862EFE-1#TRPBF from Analog Devices (formerly Linear Technology) is a two-phase, constant-frequency, peak current mode boost/SEPIC DC/DC controller driving external N-channel MOSFETs. It operates from 8.5V to 36V input, delivers up to 96% max duty cycle, supports 75kHz–500kHz adjustable switching frequency, and integrates dual 10V gate drivers with internal 10V/3.8V LDOs - used in high-voltage telecom power supplies requiring low EMI and reduced output capacitance.

For engineers reviewing the LTC3862EFE-1#TRPBF datasheet, LTC3862EFE-1#TRPBF pinout, LTC3862EFE-1#TRPBF application, or LTC3862EFE-1#TRPBF equivalent, key selection criteria include phase synchronization capability (SYNC/CLKOUT/PHASEMODE), programmable leading-edge blanking (BLANK), slope compensation gain control (SLOPE), ±1% reference accuracy, and thermal performance in the 24-lead TSSOP package with exposed PGND pad.

Technical Context

The LTC3862EFE-1#TRPBF implements a fixed-frequency, two-phase interleaved peak current mode control architecture with 180° channel phasing, reducing input/output ripple and enabling smaller passive components. Its dual independent current-sense paths (SENSE1±/SENSE2±) feed comparators referenced to ITH voltage, with slope compensation applied via SLOPE pin to prevent subharmonic oscillation at duty cycles >50%.

Internal cascaded LDOs supply critical subsystems: a 10V INTVCC regulator powers gate drivers (capable of sourcing 50mA), while a 3.8V 3V8 LDO powers analog/digital control circuitry. Phase-locking is achieved via PLL-based SYNC input (50kHz–650kHz range), with CLKOUT and PHASEMODE enabling 2-/3-/4-/6-/12-phase expansion without external timing components.

Key Specifications

Pinout & Package

Package: 24-lead plastic TSSOP (FE24), 0.65mm lead pitch, exposed thermal pad (Pin 25) connected to PGND and required to be soldered to PCB ground 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 LTC3862EFE-1#TRPBF, the I-grade variant extends operational reliability in high-temperature environments, while the QFN variant improves thermal dissipation but demands layout revision - neither offers functional enhancements, only grade or package differentiation.

Availability

LTC3862EFE-1#TRPBF is available at Aetrix Electronics and suitable for telecom power supplies, industrial HV bias generation, and automotive ADAS camera modules requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for LTC3862EFE-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. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and power management ICs, serving precision instrumentation, communications, and industrial markets.

The LTC3862 product line was designed specifically for high-efficiency, multi-phase boost and SEPIC DC/DC conversion in systems demanding tight regulation, low EMI, and scalable power architecture - targeting telecom infrastructure, test equipment, and high-reliability industrial power.

FAQ

What is the maximum achievable output voltage using LTC3862EFE-1#TRPBF in a boost configuration?

The LTC3862EFE-1#TRPBF itself does not impose a hard upper limit on output voltage; it is a controller only. Practical output voltage depends on external components: MOSFET V_DS rating, diode PIV, and output capacitor voltage rating. In published typical applications, LTC3862EFE-1#TRPBF achieves 72V output from 32V input with 96% duty cycle - confirming suitability for ≤100V systems when paired with appropriately rated passives and switches.

Does LTC3862EFE-1#TRPBF support single-phase operation, or is two-phase mandatory?

LTC3862EFE-1#TRPBF supports both configurations. It defaults to two-phase operation with 180° interleaving, but single-phase use is enabled by tying PHASEMODE to SGND and leaving one gate drive (e.g., GATE2) unused. The controller continues full functionality - current sensing, slope compensation, and frequency programming - with only one active channel.

How is the switching frequency set on LTC3862EFE-1#TRPBF, and what tolerance can be expected?

Switching frequency on LTC3862EFE-1#TRPBF is set by a resistor (R_FREQ) from FREQ pin to SGND, with nominal range 75kHz–500kHz. At R_FREQ = 45.6kΩ, f_OSC = 300kHz (typ). Frequency tolerance is ±5% over temperature and line, per datasheet specifications - sufficient for EMI filtering design without trimming.

Can LTC3862EFE-1#TRPBF drive logic-level MOSFETs, or is it limited to high-voltage types?

LTC3862EFE-1#TRPBF is optimized for high-voltage N-channel MOSFETs via its 10V INTVCC gate drive, but it can drive logic-level devices if V_GS(th) ≤ 2.5V and R_DS(on) is acceptable at 10V. However, the internal 10V LDO is not intended for logic-level optimization - for dedicated logic-level support, Analog Devices recommends the LTC3862 (non-"-1") variant, which features a 5V gate drive option.

What is the purpose of the exposed pad (Pin 25) on the LTC3862EFE-1#TRPBF TSSOP package?

The exposed pad (Pin 25) on LTC3862EFE-1#TRPBF is electrically connected to PGND and serves dual roles: (1) primary thermal path to PCB ground plane, lowering θ_JA to 38°C/W; (2) low-inductance power ground return for gate drive and sense circuits. Per datasheet, it must be soldered to a solid copper area on the PCB - floating or unconnected pads cause thermal derating and potential instability.