Sony SPP-935 Service Manual page 29

U6 TA31103F (BASE MAIN BOARD)
U7 TA31103F (HAND MAIN BOARD)
24 23 22 21 20 19
∆G
–
+
EXP
SUM
MUTE
PRE AMP AMP
VREF
–
VREF
+
THROUG
VREF
THROUG
COMP
MUTE
VREF
FILTER
FILTER IN 2
AMP 1
AMP 2 AMP
+ + +
– – –
∆G
2 4 5 7
1 3 6
U11 LP2953IM (HAND MAIN BOARD)
GND 1 16 GND
NC 2
OUTPUT 3 15 INPUT
ERROR
AMP
14 FEEDBACK
+
–
SENSE 5V TAP
4 13
SHUT DOWN 5
+
–
SHUT DOWN
COMPARATOR
DROP OUT
DETECTION AMP
+
ERROR 6
–
NC 7
GND 8 12 VREF
1.23V
AUXILLARY
11 COMP IN
COMPARATOR
10 COMP OUT
9 GND
18 17 16 15 14 13
–
–
+
+
RO1 SWITCH
AMP RO2 CONTROL
AMP
VREF
VREF
SUM
AMP
MIC AMP
+
+
–
–
9 10 11 12
8
U12 MC34118DW (BASE MAIN BOARD)
28 27 26 25 24 23 22 21
RX
ATTEN- DIAL
UATOR TONE
DETECTOR
BACKGROUND BACKGROUND
LEVEL
NOISE NOISE
DETECTOR
DETECTOR DETECTOR
LEVEL COMPARATOR COMPARATOR
DETECTOR
AGC
VCC
HYBRID HYBRID
VR VR
ATTENUATOR
AMP 2 AMP 1
+
FILTER
+
AMP
–
–
1 2 3 4 5 6 7 8
– 41 –
U14 MC34119DR2 (BASE MAIN BOARD)
8 7 6
BIAS
CIRCUIT
1 2
U17 KS58015D (BASE MAIN BOARD)
VDD 1
20 19 18 17 16 15
VREF
TEN 2
CONTROL
3
ST
CIRCUIT
GS 4
VSS 5
LEVEL
DETECTOR
OSC IN 6
OSC
OSC OUT 7 CIRCUIT
LEVEL
DETECTOR
MIC
TX
VR
AMP
+
–
9 10 11 12 13 14
U15, 16 MC74HC595AF (BASE MAIN BOARD)
5
16 15 14 13 12
VCC
+
_
3 4
D/A CONVERTER
14 TONE OUT
& MIXING
13 NC
12
D3
ROW &
DATA
11 D2
COLUMN
LATCH &
TONE
DECODER 10 D1
COUNTER
9 D0
MUTE MUTE
8 MUTE
LOGIC DRIVER
– 42 –
11 10 9
SHIFT REGISTER
LATCH
GND
2 3 4 5 6 7 8
1
PARALLEL DATA
OUTPUT