Pioneer VSX-516-K Service Manual page 117

5
A
QQ
3 7 63 1515 0
IC701 (pins 7,24,41,71,77,87,109,119)
12
Is
the voltage
1.8 V ?
Yes
IC771 (pin 1)
13
Is
the voltage
5 V ?
Yes
CN701 (pin 1)
14
Is
the voltage
5 V ?
Yes
Power supply is OK.
To STEP 3
TE
L 13942296513
Step 3: Operation of USB Media control IC
IC701 (pins 74,75)
Does the
crystal oscillator
at 12 MHz
?
Yes
USCS/USCLK (Refer to Fig. 1 and 2)
Are
USCS and USCLK
high?
Yes
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B
.
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USB Media control IC
No Check the parts and
patterns in the path.
USB Power SW output
Is pin 4
No No
(CTL) of IC771
high?
Yes
Check the parts and
Replace IC771.
patterns in the path.
USB Bus power
No
Check the parts and
patterns in the path.
XIN/XOUT
No No
Is XRST
high?
Yes
Check the parts and patterns in the path.
Replace X701, etc.
No
USCS and USCLK should be
high during operation.
Check the pattern in the path.
Check the MOTHER Assy.
Replace IC762, etc.
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8
Is pin 14
No
Check the
(CTL) of CN702
MOTHER Assy.
high?
Yes
Q Q
3 6 7 1 3 1 5
Note: Please confirm it with the USB memory connected for the content.
XRST must be high during operation.
Check the MOTHER Assy.
Fig. 1
XRST
USCS
HREQ
USDAI
Fig. 2
USCLK
USDAO
co
TREQ
.
VSX-516-K
7
9 4 2 8
0 5 8 2 9 9 4 2 8
IC953 (5 V → 3 V)
IC701
pin 72 pin 3 pins 1,2
pin 121 pin 11 pins 12,13
pin 122 pin 6 pins 4,5
pin 118 pin 8 pins 9,10
IC951 (3 V → 5 V)
IC701
pin 116 m pins 4,5 pin 6
pin 115 pins 9,10 pin 8
pin 123 pins 12,13 pin 11
7
8
9 9
A
B
C
9 9
D
CN702
pin 5
E
pin 9
pin 12
pin 10
CN702
pin 7
pin 11
pin 13
F
117
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