Мікросхема XL1509-adj

Features

Wide 4.5V to 40V Input Voltage Range

3.3V,5V,12V, and adjustable versions

Output Adjustable from 1.23V to 37V

Maximum Duty Cycle 100%

Minimum Drop Out 1.5V

Fixed 150KHz Switching Frequency

2A Constant Output Current Capability

Internal Optimize Power Transistor

High e

fficiency

Excellent line and load regulation

TTL shutdown capability

ON/OFF pin with hysteresis function

Built in thermal shutdown function

Built in current limit function

Built in second current limit function

Available in SOIC8 package

Applications

LCD Monitor and LCD TV

Digital Photo Frame

Set-up Box

ADSL Modem

Telecom / Networking Equipment

General Description

The XL1509 is a 150 KHz fixed frequency PWM buck (step-down) DC/DC converter,

capable of driving a 2A 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 second current limit

function happens, the operation frequency

will be reduced from 150KHz to 50KHz. An

internal compensation block is built in to

minimize external component count.