LTC3789 Series

High Efficiency, Synchronous, 4-Switch Buck-Boost Controller

Catalog

High Efficiency, Synchronous, 4-Switch Buck-Boost Controller

Part	Voltage - Supply (Vcc/Vdd) [Max]	Voltage - Supply (Vcc/Vdd) [Min]	Supplier Device Package	Output Type	Output Configuration	Number of Outputs	Mounting Type	Package / Case	Control Features	Synchronous Rectifier	Frequency - Switching [Min]	Frequency - Switching [Max]	Function	Duty Cycle (Max) [Max]	Operating Temperature [Min]	Operating Temperature [Max]	Output Phases	Clock Sync	Topology
Analog Devices LTC3789IGN#TRPBF	38 V	4 V	28-SSOP	Transistor Driver	Positive	2	Surface Mount	28-SSOP	Current Limit Enable Frequency Control Power Good Soft Start		200 kHz	640 kHz	Step-Up/Step-Down	90 %	-40 °C	125 ¯C	1		Buck-Boost
Analog Devices LTC3789IUFD#PBF	38 V	4 V	28-QFN (4x5)	Transistor Driver	Positive	2	Surface Mount	28-WFQFN Exposed Pad	Current Limit Enable Frequency Control Power Good Soft Start		200 kHz	640 kHz	Step-Up/Step-Down	90 %	-40 °C	125 ¯C	1		Buck-Boost

Catalog

High Efficiency, Synchronous, 4-Switch Buck-Boost Controller

Key Features

• Single Inductor Architecture Allows VINAbove, Below or Equal to the Regulated VOUT

• Programmable Input or Output Current

• Wide VINRange: 4V to 38V

• 1% Output Voltage Accuracy: 0.8V < VOUT< 38V

• Synchronous Rectification: Up to 98% Efficiency

• Current Mode Control

• Phase-Lockable Fixed Frequency: 200kHz to 600kHz

• No Reverse Current During Start-Up

• Power Good Output Voltage Monitor

• Internal 5.5V LDO

• Quad N-Channel MOSFET Synchronous Drive

• VOUTDisconnected from VINDuring Shutdown

• True Soft-Start and VOUTShort Protection, Even in Boost Mode

• Available in 28-Lead QFN (4mm × 5mm) and 28-Lead SSOP Packages

Description

The LTC3789 is a high performance buck-boost switching regulator controller that operates from input voltages above, below or equal to the output voltage. The constant-frequency, current mode architecture allows a phase-lockable frequency of up to 600kHz, while an output current feedback loop provides support for battery charging. With a wide 4V to 38V (40V maximum) input and output range and seamless, low noise transitions between operating regions, the LTC3789 is ideal for automotive, telecom and battery-powered systems.The operating mode of the controller is determined through the MODE/PLLIN pin. The MODE/PLLIN pin can select between pulse-skipping mode and forced continuous mode operation and allows the IC to be synchronized to an external clock. Pulse-skipping mode offers high efficiency and low ripple at light loads, while forced continuous mode operates at a constant frequency for noise-sensitive applications.A PGOOD pin indicates when the output is within 10% of its designed set point. The LTC3789 is available in low profile 28-pin 4mm × 5mm QFN and narrow SSOP packages.ApplicationsAutomotive SystemsDistributed DC Power SystemsHigh Power Battery-Operated DevicesIndustrial Control