UNISONIC TECHNOLOGIES CO., LTD

ULW2091

Preliminary

LINEAR INTEGRATED CIRCUIT

www.unisonic.com.tw

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Copyright © 2016 Unisonic Technologies Co., Ltd

QW-R125-044.c

NON ISOLATED BUCK

CONSTANT CURRENT LED

DRIVER IC



DESCRIPTION

ULW2091

is a high precision LED BUCK constant current driver

chip. The chip operates in the inductor current critical continuous

mode, which is suitable for the non isolated buck LED constant

current power supply with 85Vac~265Vac full range input voltage.

ULW2091

chip integrated 500V power switch by patent

demagnetization detection technology and high voltage power

supply technology, without detection and power supply for auxiliary

winding, the peripheral devices are more simple, saving the cost

and volume of the system.

ULW2091

chip with high precision current sampling circuit,

while the use of patented constant current control technology to

achieve high accuracy of the LED constant current output and

excellent line voltage regulator. The chip operates in the critical

mode of inductor current and the output current is not changed with

the increase of the inductance and the working voltage of LED.

ULW2091

has a variety of protection features, including LED

short circuit protection, under voltage protection, over temperature

adjustment function and so on.



FEATURES

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TO-92

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SOT-23-3

(JEDEC TO-236)

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3

SOT-89

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SOT-23

(JEDEC SC-59)

HSOP-8

* The integrated 500V power mos.

* The integrated high voltage power supply function.

* The inductor current critical continuous mode.

* Without auxiliary winding detection and power supply.

* The wide voltage input voltage.

* ±5% LED output current accuracy.

* The LED short circuit and open circuit protection.

* The chip power supply under voltage protection.

* The regulating function of overheating