Testing - Sony KD-34XBR2 Training Manual

In the following Waveform 6-1, both drive outputs from IC6001/pins 12 and 16 are shown (channels 1 and 2). The
outputs are complementary, the duty cycle is 50% and the frequency has dropped down from 200kHz to 85kHz
during normal operation. When the top Driver (Q6002) is ON, the bottom Driver (Q6001) is OFF.
Waveform 6-1 - Primary PS Oscillator - Normal operation - 85kHz
Channel
1
2
Time base = 2usec/div.

Testing

Chart 6-2 shows what is necessary to start and run the primary power supply and Chart 6-3 lists the voltages
of the power supply' s IC6001.
Check Point
1. R6006 (Fusible)
2. CN6005/ pin 5
3. IC6001/ pin 2
(Feedback voltage)
4. IC6001 voltages. See chart 6-3.
Chart 6-3 - IC6001 Voltages (Power ON, Video 1 input, Dark screen)
1.
3.0V
10.
10V
P M 3 3 9 4 , F L U K E & P H I L I P S
c h 1 : p k p k = 3 2 5 V
c h 1 : freq= 84.8kHz
Ch 1
T
1
Ch 2
2
C H 1 ! 1 0 0 V =
C H 2 ! 5 . 0 0 V = M T B 2 . 0 0 u s - 1 . 1 8 d v c h 1 -
Name
Top Driver Output
Bottom Driver Out
Chart 6-2 - Checks for Primary power supply operation
Normal
340Vdc P.S. Input voltage
>+15.6Vdc Pri-Pre 15V. Checks P.S. Output
1.9Vdc Feedback Voltage. Troubleshooting - If step 2 voltage is low,
measure IC6001/pin 2. If pin 2 is High (4V) - problem is
around IC6001. If pin 2 is Low (0-1V), problem is the
feedback path IC6003, PH6001.
2. 3. 4.
1.8V 2.2V 2.5V
11. 12. 13.
0V 4.5V -0.2V
Hot ground is at CN6501/pin 6 (black wire).
6. Primary Power Supply - HA-3 & RA-5a Chassis
Location Voltage
Q6002/gate 340Vp-p
Q6001/gate 12Vp-p (4.6Vdc)
Description
5. 6. 7.
0V 0V 4.5V
14. 15. 16.
-28V -32V -32V
18
8. 9.
18.4V 0V
17. 18.
-0.3V 313V