PANASONIC AN12941A

ICs for Audio Common Use
AN12941A
Audio power IC for notebook PC
Unit: mm
■ Overview
Area of no resin flash
14.00±0.10
(6.90)
(5.45)
29
(2.25)
(3.70)
6.10±0.10
8.10±0.20
56
Seating plane
The AN12941A is an amplifier IC for stereo
speakers which can output 1 W by 8 Ω or 2 W by 4 Ω.
The AGC circuit is built-in to prevent the resonance
or the vibration by the speaker's energy and the
clipping distortion what is called "broken up sound."
of the speakers.
Also, to reduce power consumption, AN12941A
has a built-in function which automatically detects the
input signal and can automatically enter power save
mode when there is no signal.
(1.00)
1.20 max.
28
■ Features
 Speaker amplifier is
1 W × 2-channel: 8 Ω, VCC = 5 V or
2 W × 2-channel: 4 Ω, VCC = 5 V
 Built-in AGC circuit
Prevention of the resonance or the vibration by
the speaker's energy and the clipping distortion
of the speaker by AGC at excessive input signal
(with AGC on/off switch).
 Built-in automatic power saving function
It detects input signals and switches on/off (with
the on/off switch for the automatic power saving).
 Operating supply voltage: VCC 3.0 V to 5.5 V/
VCC_SP 3.0 V to 5.5 V
0.20±0.05
0.10 M
Seating plane
(1.00)
0.15±0.05
0.10
0.50
(0.25)
0.10±0.10
1
0° to 8°
0.50±0.10
HSOP056-P-0300A (Lead-free package)
■ Applications
 Notebook PC, LCD monitor with speaker
4 Ω to 8 Ω
Speaker amplifier
R
L
Input4
Input3
Input2
Input1
AGC SW
AGC on level SW
Signal automatic detection SW
Audio signal detection
sensitivity SW
SP power save SW
Main signal mute SW



Standby SW
■ Block Diagram
AGC
Mix circuit
AGC
Automatic detection
Automatic power save
Publication date: April 2004
SDC00056AEB
1
AN12941A
■ Application Circuit Example
+14 dB
30
0.47 µF
Power
Save
32
33
+14 dB
35
SP GND
37
GND
38
HP out
L-channel
0.47 µF
Signal
Det.
−22 dBV
−28 dBV
8
20 kΩ
0.47 µF
47
17
−16 dBV
0 dB
0 dB
0.47 µF
4.7 µF
−16 dBV 0.47 µF
−22 dBV
−16 dBV
−22 dBV
AGC
+3 dB
+3 dB
+3 dB
0.47 µF
−2 dBV
Automatic
detection
output
47 kΩ
0.047 µF
14
13
0 dB
10
0 dB
AGC
on/off
4.7 µF
Audio automatic detection
on/off control
0.47 µF
15
GND
11
0 dB
−16 dBV
−16 dBV
−22 dBV
−28 dBV
HP out
R-channel
HP amplifier
R-channel
0.47 µF
9
0 dB
49
2.4 V
50
−22 dBV
−28 dBV 20 kΩ
VREF 8
7
Signal
on/off
6
−22 dBV
−28 dBV −6 dB
5
Standby
52
−6 dB
VREF
53
−22 dBV
−28 dBV
54
−22 dBV
−28 dBV
−6 dB
55 −22 dBV
−28 dBV
−6 dB
−2 dBV
+4 dBV
R-channel
SP out
4 Ω to 16 Ω
12
48
56
16
+9 dB
AGC
51
−16 dBV
L-channel in −22 dBV
22
20
GND
19
VREF (SP)
Det.
41
VCC _SP
23
18
40
10 µF
21
46
10 kΩ
2
Mute
Mute
10 kΩ
−16 dBV
−16 dBV 44 +3 dB
HP amplifier
L-channel
45
from beep
SP GND
Save
CTL
Control
42
GND
+9 dB
43
0.47 µF
REF
24
+14 dB
−16 dBV
1 µF 100 kΩ
Audio control
volume
V
25
39
0.47 µF
27
26
36
10 kΩ
+14 dB
31
34
SP save
on/off
28
−16 dBV
−2 dBV
+4 dBV
L-channel
SP out
4 Ω to 16 Ω
−2 dBV
VCC _SP
VCC _SP
29
−16 dBV
10 µF
VCC _SP
from modem
Supply voltage 3.3 V
Supply voltage 5 V
AGC on
lebel change
4
−6 dB
REG
3
2
Beep
−22 dBV
−28 dBV
SDC00056AEB
VCC 1
−16 dBV
−22 dBV
Audio control
volume
VREF
Signal
on/off
R-channel in
0.47 µF
STB
−16 dBV
−22 dBV
from PCcard
0.47 µF
1 µF
10 µF
SP gain high/low SW
AN12941A
■ Pin Description
Pin No.
Description
Pin No.
Description
1
VCC
29
VCC_SP L-channel
2
SP gain high/low SW
30
SP amplifier L-channel negative phase output (−)
3
REG ripple filter pin
31
SP amplifier L-channel negative phase output (−)
4
Input for PCcard
32
SP amplifier L-channel positive phase output (+)
5
Standby on/off control
33
SP amplifier L-channel positive phase output (+)
6
R-channel input
34
GND_SP L-channel
7
Main signal mute on/off control
35
SP power save control
8
VREF R-channel for volume
36
AGC on level control
9
Audio mix amplifier R-channel output
37
GND
10
Volume control signal R-channel input
38
Signal auto detection amplifier R-channel input
11
R-channel output for HP amplifier
39
Signal auto detection mix amplifier
R-channel output
12
Negative feedback pin for alarm mix
amplifier R-channel
40
AGC demodulation pin
13
Alarm mix amplifier R-channel output
41
SP amplifier L-channel input
14
AGC R-channel output
42
GND
15
GND
43
AGC L-channel output
16
SP amplifier R-channel input
44
Alarm mix amplifier L-channel output
17
Signal automatic detection on/off control
45
Negative feedback pin for alarm mix
amplifier L-channel
18
AGC on/off control
46
L-channel output for HP amplifier
19
VREF_SP
47
Volume control signal L-channel input
20
GND
48
Audio mix amplifier L-channel output
21
Demodulation pin for signal automatic detection
49
Voltage output for AGC level change
22
Signal automatic detection output
50
Signal auto detection amplifier L-channel input
23
GND_SP R-channel
51
Signal auto detection mix amplifier
L-channel output
24
SP amplifier R-channel positive phase output (+)
52
L-channel input
25
SP amplifier R-channel positive phase output (+)
53
VREF
26
SP amplifier R-channel negative phase output (−)
54
Input for modem
27
SP amplifier R-channel negative phase output (−)
55
GND
28
VCC_SP R-channel
56
Input for beep
Note) SP: Speaker
HP: Headphone
REG: Regulator
SDC00056AEB
3
AN12941A
■ Absolute Maximum Ratings
Parameter
Supply voltage
Symbol
Rating
Unit
VCC
5.75
V
VCC_SP
5.75
ICC

A
PD
517
mW
Topr
−20 to +75
°C
Tstg
−55 to +150
*1
Supply current
Power dissipation
*2
Operating ambient temperature
Storage temperature
*3
*3
1.013 ×
105
± 0.61 ×
°C
105
Operating ambient atmospheric pressure
Popr
Pa
Operating constant gravity
Gopr
9 810
m/s2
Operating shock
Sopr
4 900
m/s2
Note) *1: The values under the condition the above absolute maximum ratings and the power dissipation.
*2: Ta = 75°C, the value under the condition which this device is mounted on a four-layer printed wiring board and in addition
its radiation part is soldered. (Reference to ■ Technical Data, • Power dissipation of package HSOP056-P-0300A)
*3: Except for the storage temperature and operating ambient temperature, all ratings are for Ta = 25°C.
■ Recommended Operating Range
Parameter
Supply voltage
Symbol
Rating
Unit
VCC
3.0 to 5.5
V
VCC_SP*
3.0 to 5.5
Note) *: The values under the condition the above absolute maximum ratings and the power dissipation.
■ Electrical Characteristics at VCC = 5 V, VCC_SP = 5 V
Note) Ta = 25°C ± 2°C unless otherwise specified.
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
Circuit current
Circuit current 1A at non-signal
(VCC)
IVCCA
VCC = 3.3 V, at non-signal,
Automatic distinction: on
4.4
8.7
13.0
mA
Circuit current 2A at non-signal
(VCC_SP)
IVCCSA
VCC = 3.3 V, at non-signal,
Automatic distinction: on

400
600
µA
Circuit current 1B at non-signal
(VCC)
IVCCB
VCC = 3.3 V, at non-signal,
Power save: off
at non-automatic distinction
4.8
9.5
14.2
mA
Circuit current 2B at non-signal
(VCC_SP)
IVCCSB
VCC = 3.3 V, at non-signal,
Power save: off
at non-automatic distinction

8.1
16.2
mA
Circuit current 1C at non-signal
(VCC)
IVCCC
VCC = 3.3 V, at non-signal,
Power save: on
at non-automatic distinction
4.1
8.1
12.1
mA
Circuit current 2C at non-signal
(VCC_SP)
IVCCSC
VCC = 3.3 V, at non-signal,
Power save: on
at non-automatic distinction

400
600
µA
4
SDC00056AEB
AN12941A
■ Electrical Characteristics at VCC = 5 V, VCC_SP = 5 V (continued)
Note) Ta = 25°C ± 2°C unless otherwise specified.
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
Circuit current (continued)
Circuit current 1D at non-signal
(VCC)
IVCCD
VCC = 3.3 V, at standby mode

10
50
µA
Circuit current 2D at non-signal
(VCC_SP)
IVCCSD
VCC = 3.3 V, at standby mode

10
50
µA
Speaker amplifier (Pin 52, pin 6 → pin 24 to pin 27, pin 33 to pin 30)
L-channel audio output level
VOSPL
VIN = −22 dBV, 1 kHz, RL = 8 Ω
2.0
4.0
6.0
dBV
R-channel audio output level
VOSPR
VIN = −22 dBV, 1 kHz, RL = 8 Ω
2.0
4.0
6.0
dBV
L-channel audio output
distortion
THSPL
VIN = −22 dBV, 1 kHz, RL = 8 Ω,
to THD fifth

0.04
0.5
%
R-channel audio output
distortion
THSPR
VIN = −22 dBV, 1 kHz, RL = 8 Ω,
to THD fifth

0.04
0.5
%
L-channel audio output noise
VNSPL
At non-signal, RL = 8 Ω, A curve filter

−65
−62
dBV
R-channel audio output noise
VNSPR
At non-signal, RL = 8 Ω, A curve filter

−74
−68
dBV
L-channel maximum output
power
VM8SPL VIN = 1 kHz, at THD = 10%,
RL = 8 Ω, to THD fifth, at AGC = off
0.7
1.0

W
R-channel maximum output
power
VM8SPR VIN = 1 kHz, at THD = 10%,
RL = 8 Ω, to THD fifth, at AGC = off
0.7
1.0

W
L-channel maximum output
power
VM4SPL VIN = 1 kHz, at THD = 10%,
RL = 4 Ω, to THD fifth, at AGC = off

2.0

W
R-channel maximum output
power
VM4SPR VIN = 1 kHz, at THD = 10%,
RL = 4 Ω, to THD fifth, at AGC = off

2.0

W
Cross talk R-channel →
L-channel
VCTSPL VIN = −22 dBV, 1 kHz, RL = 8 Ω
A curve filter
64
68

dB
Cross talk L-channel →
R-channel
VCTSPR VIN = −22 dBV, 1 kHz, RL = 8 Ω
A curve filter
64
68

dB
AGC output level
VAGSPL VIN = −6 dBV, 1 kHz, RL = 8 Ω
VAGSPR A curve filter
5.5
7.0
8.5
dBV
Mix amplifier characteristic 1 (Pin 4, pin 54, pin 56 → pin 46, pin 11)
L-channel, R-channel output
level at beep signal mix
VBESPL VIN = −10 dBV, 1 kHz, pin 56 input
VBESPR
−17
−16
−15
dBV
L-channel, R-channel output
level at modem signal mix
VMDSPL VIN = −10 dBV, 1 kHz, pin 54 input
VMDSPR
−17
−16
−15
dBV
L-channel, R-channel output
level at PCcard signal mix
VPCSPL VIN = −10 dBV, 1 kHz, pin 4 input
VPCSPR
−17
−16
−15
dBV
VIN = 1 kHz, VIN at THD = 1%
0.6


V[rms]
VHPMAL VIN = 1 kHz, VIN at THD = 1%
VHPMAR
0.3


V[rms]
Each entry pin max input level
Maximum amplifier output for
the HP amplifier

SDC00056AEB
5
AN12941A
■ Electrical Characteristics at VCC = 5 V, VCC_SP = 5 V (continued)
Note) Ta = 25°C ± 2°C unless otherwise specified.
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
−75
dBV
Mix amplifier characteristic 2 (continued) (Pin 56, pin 54, pin 52, pin 4, pin 6 → pin 44, pin 13)
L-channel, R-channel mix amplifier VOFSPL VIN = −16 dBV, 1 kHz
cross talk in case of signal off
VOFSPR pins 4, 6, 52, 54, 56: input

−81
Signal detection system characteristic (Pin 52, pin 6, pin 54, pin 56, pin 4 → pin 51, pin 39)
Pre-amplifier output at L-channel
input
VSDTL
VIN = −46 dBV, 1 kHz
−22
−20
−18
dBV
Pre-amplifier output at R-channel
input
VSDTR
VIN = −46 dBV, 1 kHz
−22
−20
−18
dBV
Pre-amplifier output at beep
signal input
VSDTBE VIN = −46 dBV, 1 kHz
−22
−20
−18
dBV
Pre-amplifier output at modem
signal input
VSDTMD VIN = −46 dBV, 1 kHz
−22
−20
−18
dBV
Pre-amplifier output at PCcard
signal input
VSDTPC VIN = −46 dBV, 1 kHz
−22
−20
−18
dBV
Detection level 1 at high sensitivity VSDTTH VIN = 1 kHz
−65
−60
−55
dBV
Distinction output high level
VSDTHI VIN = 1 kHz
2.3
3.3

V
Distinction output low level
VSDTLO VIN = 1 kHz

0.1
1.0
V
Voltage holding mode
Entry signal on/off
Voltage range holding on
V7H

2.0

5.0
V
Entry signal on/off
Voltage range holding off
V7L

0.0

0.8
V
AGC on/off
Voltage range holding on
V18H

2.0

5.0
V
AGC on/off
Voltage range holding off
V18L

0.0

0.8
V
Signal automatic detection function
Voltage range holding on
V17H

2.0

5.0
V
Signal automatic detection function
Voltage range holding off
V17L

0.0

0.8
V
Sandby on/off
Voltage range holding off
V5H

2.0

5.0
V
Sandby on/off
Voltage range holding on
V5L

0.0

0.8
V
SP amplifier power save on/off
Voltage range holding off
V35H

2.0

5.0
V
SP amplifier power save on/off
Voltage range holding on
V35L

0.0

0.8
V
6
SDC00056AEB
AN12941A
■ Electrical Characteristics at VCC = 5 V, VCC_SP = 5 V (continued)
Note) Ta = 25°C ± 2°C unless otherwise specified.
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
Voltage holding mode (continued)
SP gain high/low SW
+6 dB/0 dB
Voltage range holding +6 dB
V2H

2.0

5.0
V
SP gain high/low SW
+6 dB/0 dB
Voltage range holding 0 dB
V2L

0.0

0.8
V
■ Control terminal , The mode table
Pin No.
Pin Name
Voltage of Pin
Low
High
Remarks
7
Entry signal on/off
Signal off
Signal on

18
AGC on/off
AGC off
AGC on

17
Signal automatic detection function
Automatic
distinction off
Automatic
distinction on

5
Standby on/off
STB on
STB off

35
SP power save on/off
Save on
(SP off)
Save off
(SP on)
The power saving operation
by pin 35 has priority over
any automatic detection
2
SP gain high/low SW
0 dB
+6 dB
The gain difference is about
6 dB
Pin No.
36
Voltage of Pin
Pin Name
0.5 V to 1.5 V
At the time of AGC: on,
It changes on level.
On level: −3 dB to +3 dB
Note) *: The holding range of control voltage is shown in page 6 to page 7 of ■ Electrical Characteristics.
■ Terminal Equivalent Circuits
Pin No.
Equivalent Circuits
28,
29

Description
VCC_SP:
It is the specifically designed power
pin of the speaker amplifier.
 Pin 28 is for R-channel
 Pin 29 is for L-channel
Because the big electric current
flows,it is desirable to separate from
the VCC line to the other power pin
on the board pattern.
SDC00056AEB
Corrugation
and Voltage
DC 5 V
7
AN12941A
■ Terminal Equivalent Circuits (continued)
Pin No.
24,
25,
26,
27
30,
31,
32,
33
Equivalent Circuits
VCC_SP
(5.0 V)
18 kΩ
Pin 30
33
24
27
3.6 kΩ
23,
34
45 kΩ
Corrugation
and Voltage
Speaker Output:
It is output pins of the speaker
amplifier. It becomes BTL output.
The L-channel positive phase output pin:
Pin 32, pin 33
The L-channel negative phase output pin:
Pin 30, pin 31
The R-channel positive phase output pin:
Pin 24, pin 25
The R-channel negative phase output pin:
Pin 26, pin 27
To reduce voltage loss by the wire
resistance in maximum output, it
makes output 2 pins. Also, when the
speaker amplifier saves power, too,
DC voltage is maintained.
The output impedance:
Equal to or less than 10 Ω
DC 2.2 V
AC 4 dBV
GND:
It is GND pin for the speaker
amplifier.
 Pin 23 is for R-channel
 Pin 34 is for L-channel
Because the big electric current
flows, it is desirable to separate from
the GND line to the other GND pin
on the board pattern. Also, it isn't
connected with the substrate potential
in the IC.

22
8
Pin 31
32
25
26
Description
22
Pin 32, pin 33
Pin 24, pin 25
positive
Pin 30, pin 31
Pin 26, pin 27
negative
DC 0 V
Audio signal automatic detection
Signal nothing
distinction output:
DC 0 V
It outputs the distinction result of
Signals there
the audio signal automatic detection
being
DC 3.3 V
circuit.
The output form is the open collector
output from of the NPN transistor.
Therefore, the pull rises and uses for
the power by the external resistance
(equal to or more than 10 kΩ).
Signal's there being: Output high
Signal nothing: Output low
Open collector output
The electric current ability:
Equal to or more than 100 µA
SDC00056AEB
AN12941A
■ Terminal Equivalent Circuits (continued)
Pin No.
Equivalent Circuits
21
Description
VREG (3.0 V)
90 Ω
21
90 kΩ
15,
20,
37,
42,
55
Audio automatic detecting detection Signal nothing
DC 0 V
pin:
It connects a condenser for the peak
Signals there
detection. It is the circuit which
being
DC 2 V
detects a peak after rectifying the
audio signal of the audio signal
automatic detection circuit in both
waves. By changing a capacity value,
the time which the power saving
depends on in case of the switchover
which is without signal with signal's
there being can be changed.
Signal less time:
Constant current source
Signal's there being:
Emitter follower
The output impedance: About 200 Ω
GND:
It is the GND pin of the signal system.
It is connected with the substrate
potential of the IC. Pin 15, pin 42
connect with the lead frame of the IC.
DC 0 V
VCC_SP
(5.0 V)
VREF_SP:
It is the standard voltage pin to fix
the DC bias of the speaker output.
It connects a condenser to remove a
ripple.
The output impedance: About 60 kΩ
DC 2.2 V
49-pin
(2.4 V)
Signal automatic detection function
on/off control pin:
We change an audio signal automatic
detection function in on/off. In case
of automatic detection off, it controls
power saving by speaker with the
manual with the power saving on/off
pin.
High: Function on
Low: Function off
The entry impedance:
The high impedance
DC 

19
Corrugation
and Voltage
133 kΩ
19
137 kΩ
17
9 kΩ
27 kΩ
63 kΩ
9 kΩ
45 kΩ
17
SDC00056AEB
9
AN12941A
■ Terminal Equivalent Circuits (continued)
Pin No.
Equivalent Circuits
Description
DC 1.5 V
Speaker amplifier entry:
It is the voice input pins of the
AC −16 dBV
speaker amplifier. To make offset
voltage in power saving on/off
changing by the Speaker amplifier
amplifier little, it combines capacity.
(It makes pop noise small).
Pin 16: R-channel SP amplifier entry
Pin 41: L-channel SP amplifier entry
The entry impedance: About 50 kΩ
16,
41
Pin 16
41
50 kΩ
VREF (1.5 V)
14,
43
VREG (3.0 V)
Pin 14
43
90 Ω
13,
44
12.7 kΩ
12,
45
VREG (3.0 V)
Pin 12
45
10
9 kΩ
18 kΩ
Corrugation
and Voltage
AGC amplifier output:
DC 1.5 V
It is the output pin of the AGC circuit AC −16 dBV
to hold an output clip in excessive
output of the speaker output.
Pin 14: The AGC R-channel output
Pin 43: The AGC L-channel output
The output impedance:
Equal to or less than about 10 Ω
VREG (3.0 V) Alarm mix amplifier output pins:
It is output pins of the mix amplifier
to mix an alarm signal and an audio
signal.
Pin 13: R-channel output
Pin 13
Pin 44: L-channel output
44
The output impedance:
Equal to or less than about 10 Ω
Alarm mix amplifier negative
feedback pins:
It is the negative feedback of the mix
amplifier to mix an alarm signal and
an audio signal. It is possible to adjust
in the direction which lowers the
gain of the mix amplifier in putting
resistance among above mentioned
mix amplifier output pins.
Pin 12: R-channel negative
feedback pin
Pin 45: L-channel negative
feedback pin
The entry impedance:
The high impedance
SDC00056AEB
DC 1.5 V
AC −25 dBV
DC 1.5 V
AN12941A
■ Terminal Equivalent Circuits (continued)
Pin No.
9,
48
Equivalent Circuits
Description
VREG (3.0 V)
4.6 kΩ
Pin 9
48
4.6 kΩ
10,
47
Pin 10
47
7
49-pin (2.4 V)
81 kΩ
90 kΩ
126 kΩ
6,
52
Pin 6 VREG (3.0 V)
52
25.2 kΩ
Audio signal mix amplifier output pin:
DC 1.5 V
It is the output of the mix amplifier
AC −28 dBV
to mix a signal from the modem, the
beep, the PCcard to an audio signal.
Pin 9: The R-channel output
Pin 48: The L-channel output
The output impedance:
Equal to or less than about 10 Ω
Entry for EVR:
It is the amplifier entry to adjust an
output level to the HP amplifier.
It becomes the entry of the EVR
adjustment signal.
The entry impedance:
The high impedance
VREG (3.0 V)
7
Corrugation
and Voltage
Audio signal on/off changing control pin:
It is the control pin which changes
whether to communicate an audio
signal to the amplifier to mix an
alarm signal and an audio signal. At
the time of off, only an alarm audio is
output from the mix amplifier.
High: Signal on
Low: Signal off
The entry impedance:
The high impedance
Audio signal input:
It enters a main audio signal.
Pin 6: R-channel entry
Pin 52: L-channel entry
The entry impedance: About 45 kΩ
DC 
AC −28 dBV
DC 
DC 1.5V
AC −22 dBV
25.2 kΩ
VREF (1.5 V)
SDC00056AEB
11
AN12941A
■ Terminal Equivalent Circuits (continued)
Pin No.
Equivalent Circuits
4
VREG (3.0 V)
4
25.2 kΩ
25.2 kΩ
Description
Corrugation
and Voltage
PCcard signal entry:
It is the entry pin to enter a signal
from the PCcard. With the audio
signal mix amplifier of the following
paragraph, the same signal is entered
both by L-channel and R-channel.
Also, it has the function which is the
same as the beep entry of pin 56, the
modem entry by pin 54 completely.
The entry impedance: About 45 kΩ
DC 1.5V
AC −16 dBV
Ripple removal condenser pin
for the regulator:
To remove a power ripple with the
regulator circuit to create the inner
power (VREG), it puts a condenser.
The entry impedance: About 100 kΩ
DC 1.5 V
SP gain high/low CTL:
It is the terminal which controls gain
0 dB/+6 dB of SP output.
High: +6 dB
Low: 0 dB
The entry impedance:
The high impedance
DC 
VCC :
It is the power (VCC) pin to supply
the regulator circuit to create the
inner power VREG with the voltage. It
is separating from VCC_SP of pin 28,
pin 29 fully inside. It is desirable to
separate as far as it finishes coming
out about the P board pattern, too.
DC 3.3 V
VREF (1.5 V)
3
VREG (3.0 V)
VCC (3.3 V)
243 kΩ
3
9 kΩ
207 kΩ
2
49-pin (2.4 V)
81 kΩ
90 kΩ
126 kΩ
1
12

2
SDC00056AEB
AN12941A
■ Terminal Equivalent Circuits (continued)
Pin No.
Equivalent Circuits
5
5
90 kΩ
270 kΩ
56
56
25.2 kΩ
25.2 kΩ
VREF (1.5 V)
53
VREG (3.0 V)
180 kΩ
53
180 kΩ
54
VREG (3.0 V)
54
25.2 kΩ
25.2 kΩ
VREF (1.5 V)
Description
Corrugation
and Voltage
Standby on/off changing SW:
Open voltage
DC 0 V
It changes whether or not it makes
this IC an operation condition or
whether or not it makes it a standby.
High: The operation condition
Low: Standby
In that the power changes a connected
condition to the standby, the circuit
electric current can be almost made
0.
The entry impedance: About 80 kΩ
Beep input:
It is the entry pin to enter beep
signal. The same signal is entered
both by L-channel and R-channel
with the audio signal mix amplifier
of the following paragraph. Also, it
has the function which is the same
as the PCcard signal entry by pin 4,
the modem signal entry by pin 54
completely.
The entry impedance: About 45 kΩ
DC 1.5 V
AC −22 dBV
VREF:
With the pin to fix the bias voltage
(the operation point) of the system
which the inner power (VREG) works,
it becomes 1/2VREG (V). To remove
noise, it connects a condenser with
the interval of between pin 53 and
GND.
The entry impedance: About 80 kΩ
DC 1.5 V
Modem input:
It is the entry pin to enter a signal
from the modem. With the audio
signal mix amplifier of the following
paragraph, the same signal is entered
both by L-channel and R-channel.
Also, it has the function which is the
same as the PCcard signal entry by
pin 4, the beep signal entry by pin 56
completely.
The entry impedance: About 45 kΩ
DC 1.5 V
AC −22 dBV
SDC00056AEB
13
AN12941A
■ Terminal Equivalent Circuits (continued)
Pin No.
39,
51
Equivalent Circuits
Description
VREG (3.0 V)
VREF
(1.5 V)
9 kΩ
Corrugation
and Voltage
The signal detection system
pre-amplifier negative return
terminal:
It is the output terminal for signal
detection system pre-amplifier.
Pin 39
The output impedance:
51
Equal to or less than about 10 Ω
DC 1.5 V
AC −22 dBV
The signal detection system
pre-amplifier input terminal:
It is the input terminal for signal
detection system pre-amplifier.
The entry impedance: About 10 kΩ
DC 1.5 V
AC −22 dBV
AGC detection pin:
It is the detection circuit to detect
the signal level of the AGC circuit of
the SP output for the clip prevention.
It connects a condenser for the
detection.
The entry impedance: Unsettled
DC 0 V to 1 V
0.9 kΩ
38,
50
Pin 38,
Pin 50
10 kΩ
VREF (1.5 V)
40
VREG (3.0 V)
1.8 kΩ
40
144 kΩ
18
9 kΩ
17 kΩ
63 kΩ
9 kΩ
14
49-pin
(2.4 V)
90 kΩ
18
AGC on/off control pin:
It is the pin which controls the
operating operation of the AGC
circuit of the SP output for the clip
prevention in on/off. At the time of
off, the AGC circuit doesn't work.
High: AGC on
Low: AGC off
The entry impedance:
The high impedance
SDC00056AEB
DC 
AN12941A
■ Terminal Equivalent Circuits (continued)
Pin No.
Equivalent Circuits
49
Description
VREG (3.0 V)
8.1 kΩ
49
Corrugation
and Voltage
DC output for the AGC on level
adjustment:
It is an DC voltage output terminal
for the AGC on level adjustment.
The output impedance:
Equal to or less than about 10 Ω
DC 2.4 V
It changes AGC on level:
It is the pin which changes the on
level of AGC.
The entry impedance:
The high impedance
DC 1.5 V
SP amplifier power saving
on/off control pin:
It is the pin which controls power
saving by the SP amplifier. At the
time of on in addition to the control
in case of automatic distinction
function off, too, power saving on by
pin 50 has priority over.
The entry impedance:
The high impedance
DC 1.3 V
Standard bias source for EVR:
It is possible to use as GND (the DC
bias source) AC when connecting
external EVR. It is possible to
attenuate in the AC signal without
cutting a signal system in "C".
The output impedance:
Equal to or less than about 10 Ω
DC 1.5 V
11.3 kΩ
36
36
35
49-pin (2.4 V)
81 kΩ
45 kΩ
35
128 kΩ
8
VREG (3.0 V)
VREF
DC 1.5 V
8
SDC00056AEB
15
AN12941A
■ Terminal Equivalent Circuits (continued)
Pin No.
11,
46
Equivalent Circuits
Description
VREG (3.0 V)
Pin 11
46
16
Output pins for the HP amplifier:
It is output pins for the external HP
amplifier. The signal which was
adjusted in the volume in EVR can
be output by the low impedance.
The output impedance:
Equal to or less than about 10 Ω
SDC00056AEB
Corrugation
and Voltage
DC 1.5 V
AC −28 dBV
AN12941A
■ Application Notes
 Circuit Descriptions
1. Input inverting amplifier and signal mix circuit block
 Input inverting amplifier block
1) The input impedance of each input pin is about 50 kΩ.
2) Each input impedance is ±10% of variation exists by diffusion variation.
3) The gain of the input part is able to lowered by adding resistance to input pin in series.
When addition resistance is set to Ra (kΩ)
25.2
Ga =
50 + Ra
 Signal mix circuit block
1) It is added (mix) in the inverting amplifier method.
Mix ratio is 1 to 1 for each input.
2) Connect volume to this mix amplifier output, allowing you to vary the next stage input level.
3) Pin 8 is the VREF output pin for volume reference.
Audio signal
L-channel input
48
25.2 kΩ
25.2 kΩ
PCcard input
0 dB
25.2 kΩ
52
4
Mix
External
volume
Mix
47
25.2 kΩ
56
25.2 kΩ
25.2 kΩ
Modem signal input
46
L-channel
8 V
REF
It adds to the main audio signals
in inverting amplifier form.
Mix ratio is 1 to 1.
· Signal from PCcard
· Beep signal
· Signal from modem
It becomes the volume for sound
control by external resistance change.
Gain is 0 dB at maximumvolume.
54
25.2 kΩ
Mix
Mix
Audio signal
R-channel input
0dB
Mix
25.2 kΩ
Beep input
Vol.out
audio signal
0 dB
9
25.2 kΩ
6
10
Mix
25.2 kΩ
External
volume
Vol.out
audio signal
0dB
11
R-channel
8 VREF
SDC00056AEB
17
AN12941A
■ Application Notes (continued)
2. Signal detection system mix circuit block
 Signal detection system mix circuit block
1) Each input signal in accordance with mix ratio of 1 to 1.
Signals are detected by separate systems to prevent cancellation in the case of negative phase input for main
signal R-channel and L-channel.
 Main audio signal L-channel
 Main audio signal R-channel
 Beep signal
 Signal from PCcard
 Signal from modem
2) Signal detection sensitivity can be adjusted with 10 kΩ external resistance connected between pin 50 and
pin 51 or pin 38 and pin 39.
3) The signals input via pin 38 and pin 50 first undergo double-wave rectification, and then peak detection is
performed using the external condensor connected to pin 21.
0.47 µF 10 kΩ
Audio signal
52
L-channel input
51
50
10 kΩ
Modem signal
54
input
Signal detection
Beep input 56
0.47 µF 10 kΩ
Audio signal
R-channel input
PCcard input
6
39
38
10 kΩ
2
21
0.047 µF
Note) Adjust the detection sensitivity using 10 kΩ external resistance. If noise is high for the set, use more than 10 kΩ (between
about 10 kΩ and 200 kΩ).
18
SDC00056AEB
AN12941A
■ Application Notes (continued)
2. Signal detection system mix circuit block (continued)
Detection sensitivity threshold values vs. external resistance
Detection threshold value vs. resistance constant (L-channel) between pin 50 and pin 51
Detection threshold value (L-channel input level) (dBV)
Detection threshold value (L-channel)
−40
−50
−60
−70
1
10
100
1 000
Resistance constant (between pin 50 and pin 51) (kΩ)
 Power save of speaker power amplifier
1) When input signal level is lower than a certain value due to signal automatic detection circuit, power save
of speaker power amp will be operated.
2) This automatic detecting function is able to stopped by pin 17.
3) When the automatic detection is off, it control manual control by pin 35.
4) Also when the automatic detection is on, manual power save on is prioritized.
When it control only the automatic detecting function, set pin 35 to power save off.
 Signal detecting distinction output
1) The result of automatic signal detection is output from pin 22.
VCC
51
17
50
Automatic signal detection function
on/off
VCC
Signal
detection
39
38
21
0.047 µF
SDC00056AEB
47 kΩ
22
Automatic signal detection
monitor pin
Power save of
speaker power
amplifier
VCC
35
Power save
on/off
19
AN12941A
■ Application Notes (continued)
3. Main signal on/off change and alarm signal mix circuit block
 Main signal on/off circuit
1) The speaker amplifier section is set to Mute when main signal is off.
2) High: Signal on , Low: Signal off
 Main signal level adjustment
1) The gain of this inverting amplifier can be reduced by adding external resistance in parallel between pin 12
and pin 13 or pin 44 and pin 45.
When addition resistance is set to Rd (kΩ)
18 × (9 + Rd)
Gd =
12.7 × (18 + 9 + Rd)
Headphone
9
10
3 dB
12.7 kΩ
AGC
11
18 kΩ
9 kΩ
8 VREF
13 +3 dB
12
+9 dB
VCC
7
3 dB
12.7 kΩ
48
47
AGC
46
18 kΩ
9 kΩ
8 VREF
Headphone
44 +3 dB
45
Rd
20
14
Rd
Mute
SDC00056AEB
+9 dB
43
AN12941A
■ Application Notes (continued)
4. Signal detection system mix circuit block
 AGC detection
1) The signal inputted from pin 41 and pin 16 is rectified on both waves and then mixed with L + R.
2) The above signal is peak-detected by the external part of pin 40. External is giving double-detection
constant.
3) When the voltage of pin 40 is equal or more than 0.7 V, AGC is on.
2.4 V
49 for setting
AGC level
+3 dB
44
43
AGC
41
36
+9 dB
AGC
detection
AGC
18
on/off
40
+3 dB
13
14
AGC
16
+9 dB
 The output wave at the time of AGC operation
It is the following output wave form chart at the AGC operation time.
Graph showing output wave when identical sound signals are input to two AN12941A ICs, one with AGC
set to off and the other with AGC set to on.
Using identical input signals,
VCC, VCC_SP = 5 V
RL = 8 Ω
← AGC off
← AGC on
SDC00056AEB
21
AN12941A
■ Application Notes (continued)
5. Speaker amplifier circuit block
 DC shift circuit
1) Shift circuit operating point of signal (bias voltage at a no signal) from VREF to VREF_SP.
DC voltage (speaker output) of output becomes VREF_SP.
 Speaker amplifier
1) Speaker amplifier is BTL amplifier system of 2-channel.
Power save
−10 dBV
43
41
50 kΩ
30
DC shift
0 dB
0 dB
31
33
VREF
0 dB
4 Ω to 8 Ω
Out-L (SP)
32
Power save
−10 dBV
14
16
50 kΩ
26
DC shift
0 dB
0 dB
27
24
VREF
0 dB
Muted in sync with power save
of speaker amplifier.
4 Ω to 8 Ω
Out-R (SP)
25
An operating point is shifted from
VREF to VREF_SP.
6. Control order at power supply on/off chcange
 Power supply on
When switching power on, it is recommended to use a speaker amplifier during a transient period from power
on till a stable condition of a circuit to ensure that a circuit start up smoothly by protecting from any shock
noise of a speaker circuit.
1) Control order
1. Power supply (VCC_SP, VCC): Change off to on
2. Standby control: Change on to off
3. Speaker amplifier power save control: Change on to off
22
SDC00056AEB
AN12941A
■ Application Notes (continued)
6. Control order at power supply on/off change (continued)
 Power supply on (continued)
2) Control timing
VCC_SP
(Pin 28, pin 29)
Time difference would not cause any
abnormality at VCC_SP and VCC atart up
VCC (Pin 1)
Standby reset after VCC_SP and VCC
reach normal voltage
Standby control (Pin 5)
Time difference:
Equal to or more than 1.0 sec
*1
Speaker pawer save control
(Pin 35)
Power supply on
Standby control reset
(Control voltage:
Change low to high)
Speaker pawer save
control reset (Control voltage:
Change low to high)
Note) *1: Time covering from standby control cancellation until a circuit stabilization to normal state.
It depends on the capacitance connected to reference voltage (VREF, VREF_SP) pin.
It is recommendation value of 4.7 µF.
 Power supply off
When switching power off, it is recommended to take the order of first applying power save control to a speaker
amplifier so that a circuit transient change may not effect on a speaker output.
1) Control order
1. Speaker amplifier power save control: Change off to on
2. Standby control: Change off to on
3. Power supply (VCC_SP, VCC): Change on to off
SDC00056AEB
23
AN12941A
■ Application Notes (continued)
6. Control order at power supply on/off chcange (continued)
 Power supply off (continued)
2) Control timing
VCC_SP (Pin 28, pin 29)
Time difference would not
cause any abnormality at
VCC_SP and VCC atart down
VCC (Pin 1)
Standby control (Pin 5)
Time difference:
Equal to or more than 100 msec
Speaker pawer save control
(Pin 35)
Time difference:
Equal to or more than 100 msec
Speaker pawer save control on
(Control voltage:
Change high to low)
Standby control on
(Control voltage:
Change high to low)
Power supply off
 After power supply start up (Usual operating condition)
Shock noise is likely to occur if you switch a standby control without applying a speaker power save.
Therefore, do not forget to apply speaker save before switching to standby control.
7. Power dissipation of package HSOP056-P-0300A
PD  Ta
5.000
4.280
Power dissipation PD (W)
4.000
Mounted on four layers of
stndard board
(50 × 50 × 0.8 mm3)
Rth(j-a) = 29.2°C/W
3.000
Mounted on stndard board
(50 × 50 × 0.8 mm3)
Rth(j-a) = 79.5°C/W
1.572
2.000
1.000
0.862
Independent IC
without a heat sink
Rth( j-a) = 144.9°C/W
0.000
0
25
50
75
100
125
150
Ambient temperature Ta (°C)
Note) The above characteristic is a reference value in case of design and is not a guarantee value.
24
SDC00056AEB
AN12941A
■ Application Notes (continued)
 Main characteristics
1) I/O characteristics, frequency characteristics
(1) SP I/O level, distortion characteristics (R-channel, L-channel)
AGC = Off, Automatic detection = On, SP gain setting = High, VCC = 3.3 V, VCC_SP = 5.0 V,
Input frequency = 1 kHz, R-out = 8 Ω, HPF: 400 Hz, LPF: 30 kHz
SDC00056AEB
25
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
1) I/O characteristics, frequency characteristics (continued)
(1) SP I/O level, distortion characteristics (R-channel, L-channel) (continued)
AGC = Off, Automatic detection = On, SP gain setting = Low, VCC = 5.0 V, VCC_SP = 5.0 V,
Input frequency = 1 kHz, HPF: 400 Hz, LPF: 30 kHz
26
SDC00056AEB
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
1) I/O characteristics, frequency characteristics (continued)
(2) SP I/O level, distortion characteristics (Beep)
AGC = Off, Automatic detection = Off, SP gain setting = High, VCC = 3.3 V, VCC_SP = 5.0 V,
Input frequency = 1 kHz, HPF: 400 Hz, LPF: 30 kHz
SDC00056AEB
27
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
1) I/O characteristics, frequency characteristics (continued)
(3) SP frequency level, distortion characteristics (R-channel, L-channel)
AGC = Off, Automatic detection = On, SP gain setting = High, VCC = 3.3 V, VCC_SP = 5.0 V,
Input level = −22 dBV
28
SDC00056AEB
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
1) I/O characteristics, frequency characteristics (continued)
(3) SP frequency level, distortion characteristics (R-channel, L-channel) (continued)
AGC = Off, Automatic detection = On, SP gain setting = Low, VCC = 5.0 V, VCC_SP = 5.0 V,
Input level = −16 dBV
SDC00056AEB
29
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
1) I/O characteristics, frequency characteristics (continued)
(4) SP frequency level, distortion characteristics (Beep)
AGC = Off, Automatic detection = Off, SP gain setting = High, VCC = 3.3 V, VCC_SP = 5.0 V,
Input level = −22 dBV
30
SDC00056AEB
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
1) I/O characteristics, frequency characteristics (continued)
(5) SP − AGC I/O level, distortion characteristics (R-channel, L-channel)
AGC = On, Automatic detection = On, VCC = 3.3 V, VCC_SP = 5.0 V,
Input frequency = 1 kHz, R-out = 8 Ω, HPF: 400 Hz, LPF: 30 kHz
SDC00056AEB
31
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
1) I/O characteristics, frequency characteristics (continued)
(6) SP − AGC frequency level, distortion characteristics (R-channel, L-channel)
AGC = On, Automatic detection = On, VCC = 3.3 V, VCC_SP = 5.0 V,
Input frequency = 1 kHz, R-out = 8 Ω, HPF: 400 Hz, LPF: 30 kHz
32
SDC00056AEB
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
1) I/O characteristics, frequency characteristics (continued)
(7) Mix amplifier I/O level, distortion characteristics (R-channel, L-channel)
AGC = Off, Automatic detection = Off, SP power save, VCC = 3.3 V, VCC_SP = 5.0 V,
Input frequency = 1 kHz, HPF: 400 Hz, LPF: 30 kHz
SDC00056AEB
33
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
1) I/O characteristics, frequency characteristics (continued)
(8) Mix amplifier frequency level, distortion characteristics (R-channel, L-channel)
AGC = Off, Automatic detection = Off, SP power save, VCC = 5.0 V, VCC_SP = 5.0 V,
Input level = −10 dBV
34
SDC00056AEB
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
2) VCC, temperature variation characteristics
(1) SP output level, distortion characteristics (R-channel, L-channel)
AGC = Off, Automatic detection = Off, SP gain setting = High, VCC_SP = 5.0 V, Vin = −22 dBV
Input frequency = 1 kHz, RL = 8 Ω, HPF: 400 Hz, LPF: 30 kHz
SDC00056AEB
35
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
2) VCC, temperature variation characteristics (continued)
(1) SP output level, distortion characteristics (R-channel, L-channel) (continued)
AGC = Off, Automatic detection = Off, SP gain setting = High, VCC_SP = 5.0 V, Vin = −22 dBV
Input frequency = 1 kHz, RL = 4 Ω, HPF: 400 Hz, LPF: 30 kHz
36
SDC00056AEB
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
2) VCC, temperature variation characteristics (continued)
(2) SP maximum output level characteristics (R-channel, L-channel)
AGC = Off, Automatic detection = Off, SP gain setting = High, VCC_SP = 5.0 V
Input frequency = 1 kHz, RL = 8 Ω, HPF: 400 Hz, LPF: 30 kHz
SDC00056AEB
37
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
2) VCC, temperature variation characteristics (continued)
(3) SP − AGC output level characteristics (R-channel, L-channel)
AGC = On, Automatic detection = Off, SP gain setting = High, VCC_SP = 5.0 V, P36 = 1.05 V
Vin = −6 dBV, Input frequency = 1 kHz, RL = 8 Ω, HPF: 400 Hz, LPF: 30 kHz
38
SDC00056AEB
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
2) VCC, temperature variation characteristics (continued)
(4) Mix amplifier output level, distortion characteristics (R-channel, L-channel)
AGC = Off, Automatic detection = Off, SP power save, VCC_SP = 5.0 V
Vin = −10 dBV, Input frequency = 1 kHz, HPF: 400 Hz, LPF: 30 kHz
SDC00056AEB
39
AN12941A
■ Application Notes (continued)
 Main characteristics (continued)
2) VCC, temperature variation characteristics (continued)
(5) Signal detection threshold value (R-channel, L-channel)
AGC = Off, Automatic detection = On, VCC_SP = 5.0 V
Input frequency = 1 kHz, HPF: 400 Hz, LPF: 30 kHz
40
SDC00056AEB
Request for your special attention and precautions in using the technical information
and semiconductors described in this material
(1) An export permit needs to be obtained from the competent authorities of the Japanese Government if any of
the products or technical information described in this material and controlled under the "Foreign Exchange
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applied circuits examples of the products. It neither warrants non-infringement of intellectual property right
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Consult our sales staff in advance for information on the following applications:
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required, or if the failure or malfunction of the products may directly jeopardize life or harm the human
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• Any applications other than the standard applications intended.
(5) The products and product specifications described in this material are subject to change without notice for
modification and/or improvement. At the final stage of your design, purchasing, or use of the products,
therefore, ask for the most up-to-date Product Standards in advance to make sure that the latest specifications satisfy your requirements.
(6) When designing your equipment, comply with the guaranteed values, in particular those of maximum rating, the range of operating power supply voltage, and heat radiation characteristics. Otherwise, we will not
be liable for any defect which may arise later in your equipment.
Even when the products are used within the guaranteed values, take into the consideration of incidence of
break down and failure mode, possible to occur to semiconductor products. Measures on the systems such
as redundant design, arresting the spread of fire or preventing glitch are recommended in order to prevent
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(7) When using products for which damp-proof packing is required, observe the conditions (including shelf life
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2003 SEP