IL6083 IK Semicon Co., Ltd, IL6083 Datasheet - Page 6

• Manufacturer Part Number: IL6083
• Description: Pwm Power Control Ic With Interference Suppression
• Manufacturer: IK Semicon Co., Ltd

Pins 5 and Pin 6, Short-circuit Protection and Current Sensing
Short-circuit Detection and Time Delay, t
The lamp current is monitored by means of an external shunt resistor. If the lamp current exceeds the
threshold for the short-circuit detection circuit (V
capacitor C5 is charged by a current source of I
off threshold (V
current source, I
The time delay, td, is calculated as follows:
Current Limitation
The lamp current is limited by a control amplifier to protect the external power transistor. The voltage drop
across the external shunt resistor acts as the measured variable. Current limitation takes place for a voltage
drop of V
when the short-circuit detection circuit has responded.
After a power-on reset, the output is inactive for half an oscillator cycle. During this time, the supply voltage
capacitor can be charged so that current limitation is guaranteed in the event of a short-circuit when the IC is
switched on for the first time.
Pins 7 and 8, Charge Pump and Output
Pin 8 (output) is suitable for controlling a power MOSFET. During the active integration phase, the supply
current of the operational amplifier is mainly supplied by the capacitor C
trickle charge is generated by an integrated oscillator (f
permits a gate voltage supply at a duty cycle of 100%.
T1
≈ 100 mV. Owing to the difference V
T5
dis
) is reached. Switching on the FET again is possible after a power-on reset only. The
, ensures that the capacitor C
d
5
T1
T2
ch
is not charged by parasitic currents.
- V
≈ 90 mV), the duty cycle is switched over to 100% and the
- I
dis
T2
. The external FET again is switched off after the cut-
≈ 10 mV, it ensures that current limitation occurs only
7
≈ 400 kHz) and a voltage doubler circuit. This
3
(bootstrapping). In addition, a
Rev. 00
IL6083