Philips FTV2.3 Schematic

FTV2.3

POWER SUPPLY

Chapter 09 page 1

REPAIR METHOD

Check VS and VA Output Load

SERVICE TIP: If the Vs input of the PDP is short circuited a simple test can be done: Disconnect the set from the mains. Disconnect ALL cables between PSU and PDP. Connect a regulated DC power supply (current limited to 1 A) directly to the Vs input of the YSUS board of the PDP (pin 9 of connector CN 33) and the chassis of the FTV. Ramp-up the voltage slowly to maximal 5 V. If the current increases to 1 A, the PDP is defect. The same can be done for the Vs input on the XSUS board: pin 10 of connector CN 23.

The Va inputs on the various boards can also be checked with the same procedure: The tests must be done on the connectors CN23: pin 1 (XSUS-board)

Chapter 09 page 2

CN42: pin 1 (ABUSR-board) CN52: pin 1 (ABUSL-board).

The next pages explains how to repair the power supply outside the

set, with fictive loads

Repair The Power Supply Out the Set

Chapter 09 page 3

 Short circuit On/Off switch, pin 1 and 2 connector 319.  Connect VCEGO (p13) and VSAGO (p15) of CN307 to a +2,5V from the +3,3v STBY SW.  For a regulated output voltage, connect test point VRS (pin 7) and VRA (pin 9) of CN307 to + 1V. Connect

to the two solder island near connector 307 (flex foil connector).

 Load +3,3V stby with 15 Ohm resistor (I must be 0,2A).  Load Vs with Lamp on CN323 pin 10. (lamp220V/75W I =176mA (82,3V))

 Vs Min load between 0,1 to 0,5A, Max load = 0,5A

 Load VA with lamp on CN 323 pin 1. (lamp 220V/100W I = 200mA (53,6V))

 VA Min load between 0,1A to 0,5A Max load = 2A  Load Vcc (5V) with resistor 8,2 Ohm, the Max load for VCC = 7A.  Load 3V3 with resistor 3,3 Ohms or 1,5 Ohm  Connect power supply to mains, by connector 308.

Output Connectors

CN319 P3 CN307 P3CN333 and CN323 P7

Pin 9

Power OK

Chapter 09 page 4

P3

VCEGO 2,5VVSAGO 2,5V VRA & VRS 1V

P7

Flow Chart Overview Check Points

Check +V standby power supply, + 3,3V and +5V stby on CN319.

Check Preconditioner +395V on fuse1004.

Check +Vs switched output voltage on pin 8,9,10 CN323 or pin 7,8,9 CN333 around 80……85V

Check + Va output voltage on pin 1 CN323 = around 50….55V

Chapter 09 page 5

Check + Vcc output voltage on pin 1 CN333 = 5,2V

Check + 3V3 output voltage on pin 8,9,10,11,12 of CN305 = 3,3V

Check Power OK line on pin 9 CN319, must be high (4,5V).

Switched Standby Voltages

5

n

i

P

Chapter 09 page 6

0

5

7

c

I

n

i

a

r

D

+5V Stby out +3,3V Stby out

Minimum load for the +3,3V switched Stby supply

is about 0,2A or 16 ohm

P2

Standby Supply Is Not Correct ?

Conditions for normal operating mode of the Stby supply;

Load is about 200mA on the 3,3V output

<100V

Fus.1400,

D6512, D6513, R3506

Chapter 09 page 7

Check V on

drain IC7500?

>100V

Check also

the +25V Hot from Stby PS

Reference is primary ground

Pin 1 IC7500 = 5,8V ?

Check secondary part

Short circuit and

Control loop

P2

Check Preconditioner

Drain T7610

Pin 11 Gate

Chapter 09 page 8

Pin 13 oscil.

Preconditioner output

Fuse 9004 = 395V

P5