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TS19730

Single-Stage Low THD

Buck-Boost PWM Control LED Driver

4/7

Version: A15

Typical Application Circuit

AC Input

90V~264V

MOV

Fuse

VCC

OUT

TS19730

GND

CL

COM

CS

Application Information

Start-up Current

The typical start-up current is around 45

value of start-up resistor and then reduce the power dissipation.

UVLO(Under Voltage Lockout)

A hysteresis UVLO comparator is implemented in TS19730. The turn-on and turn-off thresholds level are fixed at

17.5V and 8V respectively. This hysteresis shown in Fig.3 ensures that the start-up capacitor will be adequate to

supply the chip during start-up. For quick start-up of the LED driver, the start-up resistor should be matched with

the start-up capacitor.

17.5V

8V

LEB(Leading-Edge Blanking)

Each time the power MOSFET is switched on, a turn-on spike will inevitably occur at the sense resistor. To avoid

fault trigger, a 400ns leading-edge blanking time is built in. Conventional RC filtering can therefore be omitted.

During this blanking period, the current-limit comparator is disabled and cannot switch off the gate driver.

OCP(Over Current Protection)

The TS19730 has built-in cycle by cycle over current protection function on CL pin. As the CL pin voltage is larger

Fig. 3

Fig. 2