XL4003.pdf

Features

Wide 3.6V to 32V Input Voltage Range Output Adjustable from 0.8V to 30V

Maximum Duty Cycle 100% Minimum Drop Out 0.6V

Fixed 300KHz Switching Frequency 4A Constant Output Current Capability Internal Optimize Power MOSFET High e fficiency

Excellent line and load regulation TTL shutdown capability

EN pin with hysteresis function Built in thermal shutdown function Built in current limit function

Built in output short protection function Available in TO-252 package

Applications

LCD Monitor and LCD TV Digital Photo Frame Set-up Box ADSL Modem

Telecom / Networking Equipment

General Description

The XL4003 is a 300KHz fixed frequency PWM buck (step-down) DC/DC converter, capable of driving a 4A load with high efficiency, low ripple and excellent line and load regulation. Requiring a minimum number of external components, the regulator is simple to use and include internal frequency compensation and a fixed-frequency oscillator.

The PWM control circuit is able to adjust the duty ratio linearly from 0 to 100%. An enable function, an over current protection function is built inside. When short protection function happens, the operation frequency will be reduced from 300KHz to 60KHz. An internal compensation block is built in to minimize external component count.

Figure1. Package Type of XL4003

4A 300KHz 32V Buck DC to DC Converter XL4003 Figure4. XL4003 Typical Application Circuit 12V-5V/4A

4A 300KHz 32V Buck DC to DC Converter XL4003

4A 300KHz 32V Buck DC to DC Converter XL4003

4A 300KHz 32V Buck DC to DC Converter XL4003

Figure5. Standard Test Circuits and Layout Guides

Select R1 to be approximately 2K, use a 1% resistor for best stability.

C1 and CFF are optional; in order to increase stability and reduce the input power line noise, CIN and C1 must be placed near to VIN and GND;

For output voltages greater than approximately 10V

4A 300KHz 32V Buck DC to DC Converter XL4003

4A 300KHz 32V Buck DC to DC Converter XL4003

Figure6. XL4003 System Parameters Test Circuit (24V ~ 12V/4A)

Typical System Application for 24V ~ 5V/3A

Figure7. XL4003 System Parameters Test Circuit (24V ~ 5V/4A)4A 300KHz 32V Buck DC to DC Converter XL4003

Package Information

TO252-5L