Protection Circuit - Pioneer XW-HTP550 Service Manual

1

7.1.5 PROTECTION CIRCUIT

QQ
3 7 63 1515 0
PROTECT Operation Description
A MAIN ASSY
A
(AWU8261)
CN3401
B5P-VH
SR+ (L+) 5
SR- (L-)
4
3
NC
SL- (R-) 2
SL+ (R+)
1
SP PROTECT
B
Q3451
2SA1576A
Q3455
2SD1858X(QR)
C
C
Q3454
B
2SC2412K(QR)
E
TE
L 13942296513
DC detection circuit
SP PROTECT is set to "H"
D
Q3453 turns on, next Q3454 turns off.
In connection with it, the power supply (+VP) to IC3302 POWER IC
is lost in RY3301 relay turning off.
Therefore, an unusual state (DC output state) is canceled.
In addition, if an unusual state is canceled, since RY3301 relay turns on,
DC detection of it will be carried out again, SP PROTECT will be set to "H",
and RY3301 will repeat ON/OFF.
E Cautions: Since RY3301 relay repeats ON/OFF, a check on a feeling of hearing
can be taken at the time of abnormalities.
Since a relay repeats ON/OFF, be careful of +VP voltage at the time of diagnosis.
www
F
40
1
http://www.xiaoyu163.com
2
Q3452
2SA1576A
(QR) (QR)
C C
R3457
B B
E E 10k
NP
Q3453
(QR)
C 2SC4081
R3458
B
E 10k
GNDD
x ao
y
. i
XW-HTP550
2
http://www.xiaoyu163.com
3
8
SR+ (L+)
SR- (L-)
SL- (R-)
SL+ (R+)
VP
+B RY3301
ASR7019
(2/2)
1 2
+B
Q Q
3 6 7 1 3
u163
.
3
4
2 9 9 4 2 8
IC3302 LA4663
GNDP
MUTE
1 5 0 5 8 2 9 9 4
m
co
4
9 9
GNDP
2 8 9 9