TS19751
Taiw
an Semiconductor
5 Version: B1605
The Product is Covered by Patents and/or Pending Patent Applications
APPLICATION INFORMATION
S
tart-up Current
The typical start-up current is around 45μA
. The TS19751 has a built-in HV start-up circuit that avoids the need for
a start-up resistor.
Under Voltage Lockout (UVLO)
A hysteresis UVLO comparator is implemented in TS19751. The turn-on and turn-off thresholds level are fixed at
1
7.5V and 8V respectively. This hysteresis shown in Fig.1 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.
Leading-Edge Blanking (LEB)
Each time the power MOSFET is switched on, a turn-on spike will inevitably occur at the sense resistor. To avoid
f
ault 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.
VCC Over Voltage Clamp
VCC is clamped to 19V by an internal clamping circuit to guarantee IC normal operation.
O
ver Current Protection (OCP)
The TS19751 has built-in cycle by cycle over current protection function on CS pin. As the CS pin voltage is larger
t
han V
OCP
(0.5V), the gate output will be turned off immediately to avoid the driver board to be burned out.
Open load Protection (OLP)
To prevent the LED driver from being damaged, the TS19751 has an implemented OLP function. The open load
p
rotection will shut the gate driver when minimum off time keep shorter than 4.5uS.
Over Temperature Protection (OTP)
Internal 165℃
comparator will trigger temperature protection (OTP). OTP will shut down system, until internal
temperature back to 120℃.
Fig.1
