Analog Devices Inc. LTC3862EGN-1#TRPBF

Overview

LTC3862EGN-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% duty cycle, supports 75kHz–500kHz adjustable switching frequency, and integrates dual 10V gate drivers for high-voltage power stages - used in telecom base station power supplies requiring high step-up ratio and low output ripple.

For engineers reviewing the LTC3862EGN-1#TRPBF datasheet, LTC3862EGN-1#TRPBF pinout, LTC3862EGN-1#TRPBF application, or LTC3862EGN-1#TRPBF equivalent, key selection criteria include phase synchronization capability (SYNC/CLKOUT), programmable maximum duty cycle (DMAX), leading edge blanking control (BLANK), slope compensation tuning (SLOPE), and thermal performance in the 24-lead narrow SSOP package.

Technical Context

The LTC3862EGN-1#TRPBF implements fixed-frequency peak current mode control with two interleaved channels operating 180° out of phase, reducing input/output ripple and filter component stress. Its error amplifier compares FB voltage against a ±1% 1.223V internal reference and drives ITH to modulate peak inductor current per channel.

It features dual cascaded LDOs: a 10V INTVCC regulator (7.5V UVLO rising threshold) powers gate drivers, while a 3.8V 3V8 LDO supplies analog/digital circuitry. Phase relationships (CH1/CH2, CH1/CLKOUT) are set via PHASEMODE voltage, and PLL-based synchronization accepts 50kHz–650kHz external clocks on SYNC.

Key Specifications

Pinout & Package

Package: 24-lead narrow plastic SSOP (GN24), 0.25mm lead pitch, exposed pad not present (unlike QFN/TSSOP variants); θJA = 85°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LTC3862EGN-1#TRPBF, the QFN variant offers superior thermal dissipation for compact high-power designs, while the I-grade SSOP extends operational range into harsh environments - both retain identical control architecture, pinout, and feature set.

Availability

LTC3862EGN-1#TRPBF is available at Aetrix Electronics and suitable for telecom power supplies, industrial motor drive bias rails, automotive ADAS camera power, and test equipment high-voltage sources requiring stable component supply and long-term production continuity.

Supply support for LTC3862EGN-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 acquired Linear Technology in 2017 and maintains full product support, documentation, and manufacturing continuity for the LTC portfolio.

The LTC3862 family is designed for high-efficiency, high-step-up DC/DC conversion in space-constrained, thermally demanding applications - emphasizing precision current mode control, multi-phase scalability, and robust gate drive for N-channel MOSFETs.

FAQ

What is the maximum achievable output voltage using LTC3862EGN-1#TRPBF in a boost configuration?

The LTC3862EGN-1#TRPBF itself does not impose a hard upper limit on output voltage - it is determined by external components (MOSFET VDS rating, diode PIV, capacitor voltage rating, and layout parasitics). With its 96% max duty cycle and ability to drive high-voltage N-channel MOSFETs, the LTC3862EGN-1#TRPBF has been validated in designs delivering +72V from 24V input. For higher outputs (e.g., 100V), ensure all passive components and PCB creepage meet safety and reliability requirements.

Does LTC3862EGN-1#TRPBF support SEPIC topology, and what design considerations apply?

Yes, LTC3862EGN-1#TRPBF supports SEPIC operation using standard external component configurations. The controller's dual-channel current sensing and independent gate drive outputs allow each phase to manage one SEPIC switch leg. Key considerations include matching coupled inductors for interleaving benefits, ensuring proper transformer coupling coefficient, and configuring feedback to regulate the correct node (typically output rail). Application note AN147 provides verified SEPIC schematics and layout guidelines for LTC3862EGN-1#TRPBF.

How does the BLANK pin affect minimum on-time, and what is the recommended setting for 200kHz operation?

The BLANK pin on LTC3862EGN-1#TRPBF selects minimum on-time: SGND = 210ns, float = 290ns, 3V8 = 375ns. At 200kHz (5µs period), 290ns provides adequate margin to avoid pulse-skipping while maintaining resolution - this setting avoids false triggering from gate-drive ringing yet preserves light-load efficiency. For ultra-low input voltages (<12V), use SGND; for high-duty-cycle operation (>85%), use 3V8 to prevent premature turn-off.

Can multiple LTC3862EGN-1#TRPBF ICs be synchronized without external clock generation?

Yes - LTC3862EGN-1#TRPBF supports master-slave synchronization using only its internal PLL: one device operates in free-running mode (FREQ resistor set), while others connect their SYNC pins to the CLKOUT of the master. The internal PLL locks slave oscillators to the master's frequency and phase, achieving precise interleaving (e.g., 180° for two-phase). No external clock generator is required, simplifying system-level timing architecture and reducing BOM count.

What is the purpose of the 3V8 pin, and can it power external circuitry?

The 3V8 pin on LTC3862EGN-1#TRPBF is the output of an internal LDO powered from INTVCC, supplying regulated 3.8V to the IC's internal analog and digital control circuitry (error amplifier, comparators, logic). It is **not intended for external loads**: its current capability is limited (~1mA), and connecting external circuitry risks noise coupling, regulation degradation, or thermal overload. Always bypass 3V8 to SGND with a 1nF ceramic capacitor - never route it to external regulators or logic.