Service manual

Pin Symbol I/O Description
1 C I Control
2 L I Line Sense
3 X I External Current Limit
4 S O Source of MOSFET(GND)
5 F I Frequency
6 D I Drain of MOSFET
7.2 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
7.3 U103(TSUM16AL)
Pin Symbol I/O Description
1 NC Not connected
2 GND Ground
3 NC Not connected
4 NC Not connected
5 GND Ground
6 NC Not connected
7 NC Not connected
8 AVDD_DC I ADC Power
9 NC Not connected
10 NC Not connected
11 GND Ground
12 NC Not connected
13 NC Not connected
14 AVDD_DC I ADC Power
15 REXT External resistor 390 ohm to AVDD_ADC
16 AVDD_PLL I PLL Power
17 BIN0M I Reference ground for analog blue input
18 BIN0P I Analog blue input
19 GIN0M I Reference ground for analog green input
20
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