Nexo NXAMP4X1, Service Manual

Page: 30 / 123

NXAMP4x1
30
ON/OFF
circuit
Voltage
regulator
Soft
Start
-
+
Oscill
ator
fo Conversion
circuit
Q
R
S
+
-
Over
Heat
Detection
circuit
Drive
Circuit
F/F
Comparator
AMP
V
ref
V
IN
V
B
Vo
ON/OFF
V
NC
adj
COM
1 8
4
5
3
2
6, 7
Over
current
Detection
circuit
2
ERROR
AMP.
1
COMP.
S
50
µ
A
GROUND
SYNC.
COMP.
INV.INPUT
SOFT-START
SHUTDOWN
N.I.INPUT
DISCHARGE
5k
Ω
5k
Ω
V
REF
V
REF
V
i
R
T
C
T
S
R
9
5
7
6
3
12
15
8
10
FLIP
FLOP
TO INTRENAL
CIRCUITRY
OSCILLATOR
OUTPUT
PWM
LATCH
U.V.
LOCK
OUT
OSC.
REF.
REG.
16
4
NOR
OUTPUT B
SG1525A OUTPUT STAGE
SG1527A OUTPUT STAGE
14
NOR
V
C
OUTPUT A 11
13
OR
OUTPUT B 14
OR
V
C
OUTPUT A 11
13
FB
IN-
SCP
SCP
0.5
A
2
µ
A
2k
Ω
GND
OUT
RT
R
T
R
T
DTC
0.5V
PWM
1V
1V
UVLO
V+
0.8V
0.2V
1V
Vref
ER.AMP
Soft Start
Latch
Buffer
OSC
3
2
4
5
6 7 8
1
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
V
IN
L
V
IN
R
V
REF
1
V
REF
2
V
CC
AGND
PDWN
BYPAS
TEST
LRCK
MODE1
MODE0
FMT1
FMT0
OSR
SCKI
V
DD
DGND
DOUT
BCK
BCK
V
IN
L
Reference
V
REF
1
V
REF
2
V
IN
R
Delta-Sigma
Modulator
Delta-Sigma
Modulator
x 1/64, x 1/128
Decimation
Filter
With
High-Pass Filter
Power Supply
AGND V
CC
V
DD
DGND
Clock and Timing Control
Serial
Interface
Mode/
Format
Control
LRCK
DOUT
FMT0
FMT1
MODE0
MODE1
BYPAS
OSR
PDWN
SCKI
TEST
• NJU7630-M (X8682A0)
Regulator
PSANL: IC205
• PQ1CX12H2ZP (X6188A0)
Regulator
PSANL: IC208
• SG2525AN (X8960A0)
PW Modulator
PSANL: IC301
• PCM1803ADBR (X7357B0)
A/D Converter
CONTROL: IC035-038