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LTC3789EGN#PBF

ADILTC3789EGN#PBF

Analog Devices Inc.
Buck-Boost Regulator Positive Output Step-Up/Step-Down DC-DC Controller IC 28-SSOP
NRND3,398 in stock
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Overview

The LTC3789EGN#PBF is a high-performance switching regulator controller that operates from input voltages above, below, or equal to the output voltage. It features a proprietary current mode control architecture that provides seamless transitions between buck, boost, and buck-boost operating modes. This synchronous controller supports a wide input range of 4V to 38V and utilizes a constant frequency drive for external N-channel MOSFETs.

Why Choose This Part

The controller offers high efficiency through synchronous rectification and eliminates the need for bulky transformers or multiple power stages. Its programmable switching frequency from 200kHz to 640kHz allows engineers to optimize the trade-off between component size and thermal performance. The device also includes accurate output current sensing and a power good output for system sequencing.

Applications

Automotive Power Systems
Handles battery voltage fluctuations during engine cold-cranking and load-dump scenarios while maintaining a stable output.
Industrial Control Supplies
Provides reliable intermediate bus regulation for factory automation systems with varying input supply rails.
Distributed Power Architectures
Acts as a high-efficiency regulator in systems where the input rail may be higher or lower than the required logic or peripheral voltage.
High Power Battery-Operated Devices
Optimizes power extraction from battery packs throughout their entire discharge cycle from fully charged to depleted states.

Key Specifications

Function Step-Up/Step-Down
Topology Buck-Boost
Clock Sync No
Output Type Transistor Driver
Mounting Type Surface Mount
Output Phases 1
Package / Case 28-SSOP (0.154", 3.90mm Width)
Control Features Current Limit, Enable, Frequency Control, Power Good, Soft Start
Duty Cycle (Max) 90%
Number of Outputs 2
Output Configuration Positive
Frequency - Switching 200kHz ~ 640kHz
Operating Temperature -40degC ~ 125degC (TJ)
Synchronous Rectifier Yes
Supplier Device Package 28-SSOP
Voltage - Supply (Vcc/Vdd) 4V ~ 38V

Getting Started

Designers should use Analog Devices LTspice for initial circuit simulation and stability analysis of the compensation loop. Ensure low-ESR ceramic capacitors and high-quality MOSFETs are selected to handle the peak currents characteristic of buck-boost topologies. Evaluation boards like the DC1651A are available to demonstrate the reference layout for optimal thermal and EMI performance.