Analog Devices Inc. LTC3896EFE#TRPBF

Overview

LTC3896EFE#TRPBF from Analog Devices (formerly Linear Technology) is a high-performance, ground-referenced synchronous inverting DC/DC controller that drives all-N-channel MOSFET stages to generate regulated negative output voltages down to –60V. It operates from 4V to 140V input-to-output differential, delivers 40μA no-load quiescent current, supports phase-lockable switching up to 850kHz, and integrates OPTI-LOOP® compensation for wide output capacitance/ESR optimization - used in telecom –48V distributed power supplies.

For engineers reviewing the LTC3896EFE#TRPBF datasheet, LTC3896EFE#TRPBF pinout, LTC3896EFE#TRPBF application, or LTC3896EFE#TRPBF equivalent, key selection criteria include its true ground-referenced RUN/PLLIN/PGOOD interface, programmable DRVCC (5–10V), selectable light-load modes (Burst/Pulse-Skipping/Forced Continuous), and 38-lead TSSOP high-voltage package with exposed VOUT– pad.

Technical Context

The LTC3896EFE#TRPBF implements a constant-frequency current-mode architecture with integrated transconductance error amplifier (gm = 2.2 mmho), precision 0.8V feedback reference (±1% over temp), and OPTI-LOOP® compensation enabling stable loop response across diverse output capacitor types and ESR values. Its dual-path gate drive (TG/BG) supports synchronous N-MOSFET operation with <80ns minimum on-time and <55ns dead-time control.

It features three independent LDO paths for DRVCC: internal VIN-based (5.6–6.2V), external NMOS-based NDRV LDO (5.8–10.4V), and EXTVCC-based (5.8–10.4V), with switchover thresholds configurable via DRVUV pin. The device also includes programmable input OVLO (1.2V threshold), adjustable current limit (43–109mV sense threshold), and ground-referenced PLLIN for multi-phase synchronization without level shifters.

Key Specifications

Pinout & Package

Package: 38-Lead Plastic TSSOP (FE), Exposed Pad (Pin 39) = VOUT–, rated for –40°C to +125°C junction temperature.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar inverting DC/DC controller applications.

Compared with LTC3895EFE#TRPBF and LM5180QPWPRQ1, the LTC3896EFE#TRPBF uniquely delivers true ground-referenced control, integrated synchronous N-MOSFET drivers, and native inverting topology - reducing component count by ≥6 devices and eliminating level-shifting circuitry in negative-rail applications.

Availability

LTC3896EFE#TRPBF is available at Aetrix Electronics and suitable for telecom power supplies, industrial negative bias rails, and automotive infotainment display systems requiring stable component supply and long-term production continuity.

Supply support for LTC3896EFE#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 its high-performance analog and power management portfolio with rigorous qualification and long-lifecycle support.

The LTC3896 belongs to Linear's high-voltage DC/DC controller family, designed specifically for demanding negative-output power conversion in telecom, industrial, and automotive systems where ground-referenced control and ultra-low IQ are critical.

FAQ

What is the absolute maximum input voltage rating for the LTC3896EFE#TRPBF?

The LTC3896EFE#TRPBF has an absolute maximum input supply voltage (VIN) of 150V with respect to VOUT–. This rating applies across all operating conditions and defines the upper limit beyond which permanent damage may occur. The functional input range remains 4V to 140V (VIN + |VOUT–|), and operation near the 150V absolute max requires careful attention to layout, transient suppression, and thermal derating per the datasheet's θJA = 28°C/W specification.

How does the LTC3896EFE#TRPBF achieve ground-referenced interface functionality?

The LTC3896EFE#TRPBF achieves ground-referenced interface functionality by internally referencing its RUN, PLLIN, and PGOOD pins to the GND pin (not VOUT–), allowing direct connection to system-level ground-referenced logic, microcontrollers, or supervisors without external level shifters. This architecture is confirmed in the Pin Functions section, which explicitly states "RUN, PLLIN, and PGOOD pins are referenced to GND" and notes elimination of discrete level-shifting components as a key feature.

Can the LTC3896EFE#TRPBF generate a fixed –5V output without external resistors?

Yes, the LTC3896EFE#TRPBF can generate a fixed –5V output without external resistors by tying the VPRG pin (Pin 2) to INTVCC. In this configuration, the IC uses an internal resistor divider to regulate VFB to GND (the positive terminal of the output), resulting in a precise –5V output. The VFB pin must be connected to GND, and the datasheet confirms this mode delivers ±1% accuracy over temperature and line/load conditions.

What are the recommended decoupling requirements for the DRVCC pin on the LTC3896EFE#TRPBF?

The DRVCC pin on the LTC3896EFE#TRPBF requires a minimum 4.7µF ceramic or low-ESR capacitor connected directly to VOUT–, placed as close as possible to the pin. This is specified in the Pin Functions section for Pin 26 and reinforced in the Applications Information. Additional bulk capacitance (e.g., 47µF tantalum) may be added in parallel for high-current applications, but the 4.7µF ceramic is mandatory to ensure stable gate drive and prevent oscillation or shoot-through in the synchronous MOSFET stage.

Does the LTC3896EFE#TRPBF support synchronization with external clock sources?

Yes, the LTC3896EFE#TRPBF supports synchronization with external clock sources via the PLLIN pin (Pin 13). When an external clock is applied, the internal phase-locked loop forces the rising edge of the TG signal to align with the rising edge of the external clock. The device accepts 75kHz to 850kHz input clocks with TTL-compatible levels (0.5V low, 2.8V high referenced to GND), and maintains synchronization across all light-load modes (Burst, Pulse-Skipping, Forced Continuous).