Document
5A 300KHz 32V Buck DC to DC Converter
Datasheet XL4005
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 5A 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-263 package
Applications
LCD Monitor and LCD TV Digital Photo Frame Set-up Box ADSL Modem Telecom / Networking Equipment
General Description
The XL4005 is a 300KHz fixed frequency PWM buck (step-down) DC/DC converter, capable of driving a 5A 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.
Rev 2.2
Figure1. Package Type of XL4005
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5A 300KHz 32V Buck DC to DC Converter Pin Configurations
Datasheet XL4005
Figure2. Pin Configuration of XL4005 (Top View) Table 1 Pin Description
Pin Number 1
2 3 4 5
Pin Name GND
FB SW EN VIN
Description
Ground Pin. Care must be taken in layout. This pin should be placed outside of the Schottky Diode to output capacitor ground path to prevent switching current spikes from inducing voltage noise into XL4005. Feedback Pin (FB). Through an external resistor divider network, FB senses the output voltage and regulates it. The feedback threshold voltage is 0.8V. Power Switch Output Pin (SW). SW is the switch node that supplies power to the output. Enable Pin. Drive EN pin high to turn on the device, drive it low to turn it off. Supply Voltage Input Pin. XL4005 operates from a 5V to 32V DC voltage. Bypass Vin to GND with a suitably large capacitor to eliminate noise on the input.
Rev 2.2
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5A 300KHz 32V Buck DC to DC Converter Function Block
Datasheet XL4005
Figure3. Function Block Diagram of XL4005
Typical Application Circuit
VIN
CIN C1 220uF/50V 105
VIN 5
3 SW
L1 33uH/5A
XL4005
D1 MBRD1045G
EN 4 1 2 FB GND
C2 COUT 105 330uF/25V
R2 16K
CFF 33nF
VOUT
R1 3K
INPUT 24V OUTPUT 5V/5A VOUT=0.8*(1+R2/R1)
Figure4. XL4005 Typical Application Circuit (24V~5V/5A)
Rev 2.2
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5A 300KHz 32V Buck DC to DC Converter
Datasheet XL4005
Ordering Information
Order Information XL4005E1
Marking ID XL4005E1
Package Type Packing Type Supplied As
TO263-5L
800 Units on Tape & Reel
XLSEMI Pb-free products, as de.