SAMHOP Microelectronics Corp.
6 CHANNELS VOLUME CONTROLLER
SM7346
GENERAL DESCRIPTION
The SM7346 is 6 channels electronic volume
controlled by 3-wire serial data. The IC is suitable
for use in DVD systems and AV.
FEATURES
* 4 Output ports
* Built-in microcomputer interface circuit con-
trolled by 16-bit serial data.
* Electronic volume
Volume level: 0dB~-79dB, -
∞
dB(1dB/step)
* Tone control
Bass/Treble, 0dB~+10dB(2dB/step)
APPLICATIONS
* DVD
* Home Audio Equipment
* AV
PIN ASSIGNMENTS
OUT4
OUT3
OUT2
OUT1
AVDD
SWin
GNDS
SRin
SLin
GNDC
Cin
GNDR
Rin
GNDL
Lin
BYPASSR
BYPASSL
LTRE
LBASS3
LBASS2
LBASS1
1
2
3
4
5
6
7
8
9
1
0
1
1
2
1
3
1
4
1
5
1
6
1
7
1
8
1
9
2
0
2
1
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
DVDD
CLK
DATA
LATCH
DGND
AGND
SWout
SRout
SLout
Cout
Rout
Lout
AVSS
CL1
CL2
CR1
CR2
RTRE
RBASS3
RBASS2
RBASS1
OUT4
OUT3
OUT2
OUT1
AVDD
SWin
GNDS
SRin
SLin
GNDC
Cin
GNDR
Rin
GNDL
Lin
BYPASSR
BYPASSL
LTRE
LBASS3
LBASS2
LBASS1
NC
1
2
3
4
5
6
7
8
9
1
0
1
1
2
1
3
1
4
1
5
1
6
1
7
1
8
1
9
2
0
2
1
2
2
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
DVDD
CLK
DATA
LATCH
DGND
AGND
SWout
SRout
SLout
Cout
Rout
Lout
AVSS
CL1
CL2
CR1
CR2
RTRE
RBASS3
RBASS2
RBASS1
NC
SDIP 42PIN
TSSOP
44PIN
Page 1
MAY.2003
SAMHOP Microelectronics Corp.
6 CHANNELS VOLUME CONTROLLER
SM7346
BLOCK DIAGRAM
C input
SW input
SL input
SR input
BypassL
BypassR
volume
C output
SW output
SL output
SR output
tone
L input
R input
volume
L output
R output
μ
-com
interface
Latch Data CLK
Page 2
MAY.2003
SAMHOP Microelectronics Corp.
6 CHANNELS VOLUME CONTROLLER
PIN DESCRIPTION (Pin count base on 42pin SDIP)
Pin No.
1
2
3
4
5
7
10
12
14
6
8
9
11
36
35
34
33
13
15
16
17
31
32
18
25
19
24
20
23
21
22
26
28
27
29
31
32
30
37
38
39
40
41
42
Symbol
OUT4
OUT3
OUT2
OUT1
AVDD
GNDS
GNDC
GNDR
GNDL
SW in
SR in
SL in
C in
SW out
SR out
SL out
C out
R in
L in
BYPASSR
BYPASSL
L out
R out
LTRE
tone Treble cycle control
RTRE
LBASS3
RBASS3
LBASS2
RBASS2
LBASS1
RBASS1
CR2
CL2
CR1
CL1
L out
R out
AVSS
AGND
DGND
LATCH
DATA
CLK
DVDD
L.R Volume INPUT
L OUTPUT
R OUTPUT
Analog negative Power supply
Analog GND
Digital GND
Latch INPUT
Data INPUT
Clock INPUT Forward data
Digital Power supply
27,29
70 K
Ω
(TYP)
18 to 22 K
Ω
(TYP)
SM7346
Function
Port OUTPUT
Analog positive Power supply
GND
OUTPUT: PMOS
Transistor
open drain
Circuit
DVDD(=5V)
1 to 4
+7V
Connect to analog GND
Volume INPUT
6,8,9,11
18 to 22 K
Ω
(TYP)
33,34,35,36
Volume OUTPUT
Tone INPUT
L.R Volume INPUT
in BYPASS mode
L OUTPUT
R OUTPUT
16,17
13,15
70 K
Ω
(TYP)
70 K
Ω
(TYP)
31,32
18 to 22 K
Ω
(TYP)
18,25
tone Bass cycle control
19,24
2.3 K
Ω
(TYP)
20,23
21,22
Tone OUTPUT
26,28
31,32
-7V
39,40,41
S
INPUT:schmitt trigger type
+5V
Page 3
MAY.2003
SAMHOP Microelectronics Corp.
6 CHANNELS VOLUME CONTROLLER
SM7346
PIN CONFIGURATION AND IC INTERNAL BLOCK DIAGRAM ( Pin count base on 42pin )
OUT4
OUT3
OUT2
OUT1
SWin
1
2
3
4
6
volume
OUTPUT
PORT
MCU
volume
I/F
42
DVDD
41
40
39
38
CLK
DATA
LATCH
DGND
36
8
volume
9
34
33
Cin
11
volume
32
31
13
volume
30
29
28
27
26
35
SW out
SRout
SLout
Cout
Rout
Lout
AVSS
CL1
CL2
CR1
CR2
SRin
SLin
Rin
Lin
BYPASSR
BYPASSL
15
16
17
volume
AVDD
5
tone
tone
Page 4
MAY.2003
SAMHOP Microelectronics Corp.
6 CHANNELS VOLUME CONTROLLER
SM7346
ABSOLUTE MAXIMUM RATINGS
Symbol
Vsupply
Pd
K
θ
Topr
Tstg
Parameter
Supply Voltage
Power dissipation
Thermal derating
Operating temperature
Storage temperature
Conditions
AVDD-AVSS
Ta<25
o
C
Ta>25
o
C
*standard board
Ratings
16.0
1000
10
-20~+75
-40~+125
Unit
V
mW
mW /
o
C
o
C
o
C
THERMAL DERATING (MAXIMUM RATING)
Standard board
1.5
POWER DISSIPATION pd[W]
1.0
0.5
0
25
50
75
100
125
150
AMBIENT TEMPERATURE Ta [
℃
]
Page 5
MAY.2003