TS19377CSRLG datasheet(4/7 Pages) TSC

4 / 7 page

TS19377

2A Buck (Step-down) WLED Driver

4/7

Version: A11

Function Descriptions

PWM Control

The TS19377 consists of DC/DC converters that employ a pulse-width modulation (PWM) system. In converters of

the TS19377, the pulse width varies in a range from 0 to 100%, according to the load current. The ripple voltage

produced by the switching can easily be removed through a filter because the switching frequency remains

constant. Therefore, these converters provide a low-ripple power over broad ranges of input voltage and load

current.

Setting ILED Current

Application circuit item shows the basic application circuit with TS19377 adjustable output version. The external

resistor sets the LED output current according to the following formula:

ILED=(0.25V/R2)

Resistor select for LED output current setting

ILED

350mA

0.715

87.5mW

750mA

0.333

189mW

1000mA

0.250

250mW

RDS(ON) Current Liming

The current limit threshold is setting by the internal circuit.

Compensation

Please refer the table of application circuit. For DC input, the option circuit for compensation is connecting R4 and

a 1N4148 diode to VOUT. In order to protect short circuit and thermal shutdown release for LED.

TS19377CSRLG Datasheet(PDF) 4 Page - Taiwan Semiconductor Company, Ltd