C338
104
C339
104
R289
10K
C2134
105
C2135
102
R287
150R
OKA#
C2133
105
R277
0R(DNS)
R276
0R
DV33
R288
10K(NC)
M0
1
MCLK
2
VL
3
SDOUT
4
GND
5
VD
6
SCLK
7
LRCLK
8
RST
9
AINL
10
VQ
11
AINR
12
VA
13
REF_GND
14
FILT+
15
M1
16
U203
CS5340
SACLK
SBCLK
SLRCK
DV33
U2RST#
C2131
104
C2130
105
C2149
104
C2158
104
C2132
105
AMDATA
DV33
DV33
R278
0R(DNS)
R279
0R
DV33
TC220
47uF/16V
OKL
OKR
Figure 3.2.10.3 External Karaoke signal input and output diagram
3.2.11 Mute circuit and power-off quieting circuit
1. The circuit schematic diagram is shown as the following figure 3.2.11.1:
Figure 3.2.11.1 Mute and power-0ff quieting circuit
2. Working principle: under the control of I C to MT1389, CS4360 sends 3 mute control signals,
MUTE1, MUTE2, MUTE3 from pin 28, 25 and 18 which is added to mute circuit. The generated mute
control signal MUTE-1 is added to the base electrode of each switching tubeQ205 - Q210 of 6-path
analog channel to make the switching tube and make audio signal bypass into ground to reach the
purpose of mute. The working mechanism is that when no audio signal comes to a certain path, CS4360
changes the mute control signal corresponding with this path to high level. After pressing MUTE button,
3-path mute signals all change to high level.
2
When working normally (playing discs), only one path signal of the 3-path signals, MUTE1, MUTE2
and MUTE3 changes into low level, now Q211 is on. The collector electrode of Q211 is high level; Q212
is also on and its collector electrode is low level; Q213 is cutoff; MUTE-1 is low level and sound outputs
normally.
R2108
10K
+9V
R2109
10K
R2104
1K
VD205
1N4148
VCC
R2103
1K
AGND
VD206
1N4148
-9V
MUTE-1
TC235
100uF/10V
AGND
R2106
10K
Q212
2SC1815-YS
Q213
1015-S
Q214
1015-S
MUTE1
Q211
1015-S
R2102
1K
R2101
10K
VD205
1N4148
VD206
1N4148
VD207
1N4148
MUTE2
MUTE3
TC238
100uF/10V
VCC
R2105
10K
A
B
C
D
E
F
G
H
I
J
k
L
M
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