Dell E2209Wf, Руководство по обслуживанию

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Service Manual
19
8.3 U850 (
LD7552B
, PWM Power Controller)
Pin Symbol I/O Description
1 GND Ground
2 COMP I Voltage feedback pin(same as the COMP pin in
UC384X).By connecting a photo-coupler to close
the control loop and achieve the regulation.
3 VCC I Supply voltage pin
4 RT I This pin is to program the switching frequency. By
connecting a resistor to ground to set the switching
frequency.
5 NC Unconnected pin
6 CS I Unconnected pin
7 VCC I Supply voltage pin
8 OUT O Gate drive output to drive the external MOSFET
8.4 U1 ( INL833 , CCFL Inverter controller IC)
Pin Symbol I/O Description
1
VSEN
I
Voltage sense Feedback
2
SSTCMP
I
Capacitor for soft-star and loop
compensation
3
CT
I
Timing resistor and capacitor for operation
and striking frequency
4
RT1
I
Timing resistor for striking frequency
5
GNDA Signal Ground
6
PDR2
O
High side Driver output2
7
GNDP Power Ground
8
NDR2
O
Low side Driver output2
9 NDR1
O
Low side Driver output1
10 PDR1
O
High side Driver output1
11 VDDA
I
Input power Pin
12 TIMER
I
Timing
capacitor for Delay Timer
13 PWM
I
External PWM Dimming Input
14 ISEN
I
Current sense feedback
15 OVPT
I
Over-voltage protection threshold voltage
16 ENA
I
IC
Enable/Disable