Sony KV-32HS500 Training Manual page 37

In vertical shut down mode, only the video is muted, the AC power and Audio remain ON and the Stby/
Timer LED flashes a 4X sequence.
DA-4 Regulated 5V and White Balance Protection Circuit
M BOARD
(REG. 5V
Q2314
PROTECTION)
R2300
D2310
3.6V
R2298
O
UNREG
IC504
7V I
5V REG.
G
A BOARD
FIGURE 4-5 - DA-4 REG. 5V AND WHITE BALANCE PROTECTION CIRCUITS
Regulated 5V Protection Circuit
(Reference Figure 4-5)
The regulated 5V line is monitored using Q2314 and Zener diode D2310 (3.6V) on the M-board. The output of
the 5V regulator IC504 is applied to the emitter of Q2314. In normal operation Q2314 is turned ON and D2310
is conducting, holding the base at 3.6V. Approximately 2.8V is applied to System Control IC2300/pin 43, indicating
proper level of the regulated 5V line.
If the 5V line falls below approximately 4.5V at the emitter of Q2314, D2310 will stop conducting, Q2314 will turn
OFF and a Low will be applied to IC2300/pin 43. IC2300/pin 69 will then turn OFF the AC relay.
The AC relay shuts down and the Stby/Timer LED flashes a 6X sequence.
IC2300 SYSCON
I-LB-ERR
43
2.8V
R2375
R2399
C2361
12V
R9068
R9012
10.6V
12V
IC9001
RED
IO-SDAT
81
52
IC2801
CRT DRIVE
24
R9013
+
C9017
Q9007
Q9015
R9039
R9020
11V
12V
11V
7 7
IK
IK
IC9002
GREEN
(WHITE BALANCE PROTECTION)
NOTE: IK_OUT ON HS MODELS
IS IC9001, 9002, 9003/PIN 5
35
4. DA-4 & DA-4X Protection Circuits
AC RELAY
69
RY6501
D BOARD
IK_IN
R9006
12V
Q9001
CH/CX BOARD
R9012
Q9013
R9025
11V
12V
7
IK
IC9003
BLUE
B BOARD
NOTE: 11V
WITH
WHITE
RASTER
C31P15-4-5 10/28/02