降压型直流电源变换器芯片(大功率型)XL4003

Features
􀂄 Wide 5V 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 efficiency
􀂄 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
􀂄 Di*al 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 T*e of XL4003