Analog Devices Inc. LTC3672BEDC-2#TRPBF

Overview

LTC3672BEDC-2#TRPBF from Analog Devices (formerly Linear Technology) is a monolithic triple-output power management IC integrating a 400mA synchronous buck regulator and two 150mA fixed-output LDOs in a single 2mm × 2mm DFN package. It delivers 1.2V (buck), 2.8V (LDO1), and 1.8V (LDO2) from a 2.9V–5.5V input, supporting single-cell Li-ion/Li-polymer systems and low-voltage ASIC/FPGA power domains with ±2.5% reference accuracy and 2.25MHz constant-frequency operation.

For engineers reviewing the LTC3672BEDC-2#TRPBF datasheet, LTC3672BEDC-2#TRPBF pinout, LTC3672BEDC-2#TRPBF application, or LTC3672BEDC-2#TRPBF equivalent, this device is selected for compact multirail power delivery where minimal external components (one inductor, five capacitors), internal compensation, and coordinated enable control are critical - especially in handheld, PDA, GPS, and RF chipset applications requiring tight voltage regulation and fast transient response.

Technical Context

The LTC3672BEDC-2#TRPBF employs a current-mode synchronous buck architecture operating at a fixed 2.25MHz frequency down to no-load via cycle-skipping, with internal soft-start (200μs for buck, 100μs per LDO) and slew-rate-controlled SW node to reduce EMI. Its three outputs share a single ENALL pin for simultaneous turn-on/turn-off, and regulation is maintained across –40°C to 85°C with internal 800mV reference and ±2.5% output accuracy.

Each output features dedicated input paths: VIN powers the buck and LDO2; VIN1 (tied to VIN or lower) powers LDO1. The buck supports 100% duty cycle near dropout, while LDO1 and LDO2 exhibit 135mV and 290mV dropout at full load respectively, enabling stable operation under varying input conditions typical in battery-powered systems.

Key Specifications

Pinout & Package

8-lead plastic DFN (2mm × 2mm, 0.75mm height) with exposed thermal pad (Pin 9, GND). Requires soldering of exposed pad to PCB ground plane for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar triple-output PMIC applications.

Compared with LTC3672B-1 and LTC3445, the LTC3672BEDC-2#TRPBF offers the smallest footprint (4mm²), lowest quiescent current, and fixed-output simplicity ideal for cost-sensitive, space-constrained portable electronics - whereas LTC3672B-1 serves inverted voltage needs and LTC3445 adds programmability at the expense of size and IQ.

Availability

LTC3672BEDC-2#TRPBF is available at Aetrix Electronics and suitable for mobile handset power, portable GPS receivers, FPGA I/O bank supply, and RF chipset biasing requiring stable component supply across production lifecycles.

Supply support for LTC3672BEDC-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 its high-performance analog and power management portfolio. Linear pioneered precision DC/DC conversion and integrated PMICs for demanding portable applications.

The LTC3672B series was designed specifically for space-constrained, battery-powered systems requiring multiple low-noise, low-dropout rails with minimal external components - targeting handheld, medical, and industrial edge devices.

FAQ

What is the maximum output current capability of each regulator in the LTC3672BEDC-2#TRPBF?

The LTC3672BEDC-2#TRPBF provides 400mA from its synchronous buck regulator (1.2V output), 150mA from LDO1 (2.8V output), and 150mA from LDO2 (1.8V output). These ratings are guaranteed over the full –40°C to 85°C operating temperature range with appropriate thermal management and input voltage margins. Exceeding these currents may trigger current limiting or thermal shutdown.

Does the LTC3672BEDC-2#TRPBF require external compensation components for stability?

No, the LTC3672BEDC-2#TRPBF features fully internal loop compensation for both the buck regulator and LDOs. This eliminates the need for external compensation networks, simplifying design, reducing component count, and ensuring robust stability across all operating conditions with only the specified minimum output capacitors (e.g., 4.7μF for buck, 1μF for each LDO).

How does the ENALL pin control power sequencing in the LTC3672BEDC-2#TRPBF?

The ENALL pin on the LTC3672BEDC-2#TRPBF provides unified enable/disable control: driving it high (>1.2V) turns on all three outputs with internal soft-start timing (200μs for buck, 100μs for each LDO), while pulling it low (<0.4V) shuts down all regulators simultaneously. An internal 5.5MΩ pulldown resistor ensures safe default-off behavior during power-up or floating conditions.

What is the dropout voltage specification for LDO2 in the LTC3672BEDC-2#TRPBF?

LDO2 in the LTC3672BEDC-2#TRPBF has a typical dropout voltage of 290mV at 150mA load and 25°C, with a maximum of 400mV across temperature. This means LDO2 can maintain 1.8V regulation as long as VIN remains ≥2.2V (1.8V + 0.4V), making it suitable for operation across the full 2.9V–5.5V input range including end-of-discharge battery voltages.

Can the LTC3672BEDC-2#TRPBF operate with input voltages below 2.9V?

The absolute maximum rating allows VIN down to –0.3V, but the functional input range is strictly 2.9V to 5.5V per datasheet specifications. Below 2.9V, undervoltage lockout (UVLO) activates at ~1.7V (with 12mV hysteresis), disabling all outputs. Operation between 1.7V and 2.9V is undefined and not characterized - sustained use below 2.9V risks regulation failure or erratic behavior.