IL6083 IK Semicon Co., Ltd, IL6083 Datasheet - Page 3

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

Pin 1, Supply Voltage, V
Overvoltage Detection
Stage 1
If overvoltages of V
at V
Stage 2
If V
external transistor remains at the potential of the IC ground, thus producing voltage sharing between FET
and lamps in the event of overvoltage pulses (e.g. , load dump). The short - circuit protection is not in
operation.
At V
detection stage 2, the lamp voltage V
V
V
V
Undervoltage Detection
In the event of voltages of approximately V
short-circuit detection is reset.
A hysteresis ensures that the FET is switched on again at approximately V
Pin 2, GND
Ground-wire Breakage
To protect the FET in the case of ground-wire breakage, a 1 MΩ resistor between gate and source is
recommended to provide proper switch-off conditions.
Pin 3, Control Input
The pulse width is controlled by means of an external potentiometer (47 kΩ). The characteristic (angle of
rotation/duty cycle) is linear. The duty cycle can be varied from 18 to 100%. It is possible to further restrict
the duty cycle with the resistors R
In order to reduce the power dissipation of the FET and to increase the lifetime of the lamps, the IC
automatically reduces the maximum duty cycle at pin 8 if the supply voltage exceeds V
protected against short-circuit to V
Pin 4, Oscillator
The oscillator determines the frequency of the output voltage. This is defined by an external capacitor, C
is charged with a constant current, I, until the upper switching threshold is reached. A second current source
is then activated which taps a double current, 2 x I, from the charging current. The capacitor, C
discharged at the current, I, until the lower switching threshold is reached. The second source is then
switched off again and the procedure starts once more.
Lamp
S
GS
= supply voltage of the IC at overvoltage detection stage 2
Batt
Batt
= gate - source voltage of the FET
Batt
= V
> 28.5 V (typically), the voltage limitation of the IC is reduced from V
< 18.5 V (hysteresis).
approximately < 23 V, the overvoltage detection stage 2 is switched off. Thus, during overvoltage
Batt
- V
S
- V
Batt
GS
> 20 V (typically) occur, the external transistor is switched off, and switched on again
S
or V
1
Batt
and R
lamp
and ground (V
Batt
Functional Description
is calculated as follows:
2
(see Figure 4).
Batt
< 5.0 V, the external FET is switched off and the latch for
Batt
≤ 16.5 V).
Batt
S
= 26 V to 20 V. The gate of the
≥ 5.4 V.
2
= 13 V. Pin 3 is
Rev. 00
IL6083
2
, is thus
2
. It