Service manual

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4.8 Key Parts Pin Assignment

4.8.1 IC802 (NCP1337, Power Control IC)

Pin Symbol I/O Description

1 BO I Brown−out and external triggering

2 FB I Sets the peak current setpoint

3 CS I Current sense input and overpower compensation adjustment

4 GND IC ground

5 DRV O Output driver

6 Vcc I IC supply

7 NC N/A N/A

8 HV I High−voltage pin

4.8.2 IC501 (OZ9938GN, CCFL inverter controller IC)

Pin No. Symbol I/O Description

1 DRV1 O Drive output

2 VDDA I Supply voltage input

3 TIMER I Timing capacitor to set striking time and shut down delay time

4 DIM I

Analog dimming or Internal LPWM dimming or external PWM pulse input

for dimming function

5 ISEN I Current sense feedback

6 VSEN I Voltage sense feedback

7 OVPT I Over-voltage/over-current protection threshold setting pin

8 NC

9 NC

10 ENC I ON/OFF control of IC

11 LCT I

Timing capacitor to set internal PWM dimming frequency and also a pin for

analog dimming selection

12 SSTCMP I Capacitor for soft start time and loop compensation

13 CT I Timing resistor and capacitor for operation and striking frequency

14 GNDA Ground for analog signals

15 DRV2 O Drive output

16 PGND Ground for power paths

4.8.3 U105(TSUM56AL-1)

Pin Symbol I/O Description

1 NC Not connected

2 GND Ground

3 NC Not connected

4 NC Not connected

VX1935wm-3