Features

• High Voltage Operation: Up to 60V
• Large 1 Ohm Gate Drivers (with 5V Supply)
• No Current Sense Resistor Required
• Step-Up or Step-Down DC/DC Converter
• Dual N-Channel MOSFET Synchronous Drive
• Excellent Line and Load Transient Response
• Programmable Constant Frequency: 100kHz to 600kHz
• ±1% Reference Accuracy
• Synchronizable up to 600kHz
• Selectable Pulse Skip Mode Operation
• Low Shutdown Current: 25µA Typ
• Programmable Current Limit
• Undervoltage Lockout
• Programmable Soft-Start
• 16-Pin Narrow SSOP and 28-Pin SSOP Packages

Typical Application

Description

The LTC3703-5 is a synchronous step-down switching regulator controller that can directly step-down voltages from up to 60V, making it ideal for telecom and automotive applications. The LTC3703-5 drives external logic level N-channel MOSFETs using a constant frequency (up to 600kHz), voltage mode architecture.

A precise internal reference provides 1% DC accuracy. A high bandwidth error amplifier and patented* line feed forward compensation provide very fast line and load transient response. Strong 1W gate drivers allow the LTC3703-5 to drive multiple MOSFETs for higher current applications. The operating frequency is user programmable from 100kHz to 600kHz and can also be synchronized to an external clock for noise-sensitive applications. Current limit is programmable with an external resistor and utilizes the voltage drop across the synchronous MOSFET to eliminate the need for a current sense resistor. For applications requiring up to 100V operation, refer to the LTC3703 data sheet.