Type

Package

Marking

TLE4309G

PG-TO263-7-1

TLE4309

Adjustable Linear Low Dropout LED Driver

TLE4309

PG-TO263-7

Datasheet

1

Rev. 1.0, 2007-03-20

Features

•

Adjustable constant current up to 500 mA

•

Operating supply voltage range 4.5 V to 24 V

•

Maximum supply voltage up to 45 V

•

Low dropout voltage

•

PWM / ENABLE input

•

<< 1 µA quiescent current when disabled

•

Overtemperature protection

•

Short circuit proof

•

Reverse polarity protection

•

Operating junction temperature range: -40

°C to 150 °C

•

Suitable for applications up to 85 °C ambient temperature.

•

Green Product (RoHS compliant)

Functional Description

The TLE4309 is an integrated adjustable constant current source for driving loads up to

500 mA. The output current level can be adjusted with an external shunt resistor.

Supplying high power LEDs with the TLE4309 ensures constant brightness independent

from supply voltage or LED forward voltage spread. Therefore, LED lifetime is extended

by protecting from overcurrent and overtemperature

The PWM/EN input permits LED brightness regulation by pulse width modulation.

Setting the pin to “low” switches off the IC entirely. Due to the high impedance of the

PWM/EN input, the TLE4309 can be used as a protected high side switch.

Protection circuits prevent from damage to the IC in case of overload, short circuit, and

reverse polarity. A chip temperature monitoring circuit shuts off the power stage and

prevents the IC from destruction under fault conditions.

In case of negative input voltage, a leakage current is flowing only from the output to the

input, hence the LED are protected against reverse supply. Input voltage peaks up to

45 V are absorbed by the IC, preventing the LEDs from overcurrent.

The TLE4309G is provided in the surface mounted PG-TO-263 package with excellent

thermal resistance.