PANASONIC AN7124

ICs for Audio Common Use
AN7124
Dual 3.1 W Audio Power Amplifier
■ Overview
Unit : mm
The AN7124 is a monolithic integrated circuit designed
for dual audio power amplifier of portable radio cassette.
(1.3)
12
7.7±0.3
(10.0)
29.6±0.3
(1.27)
+0.15
0.6 –0.05 (1.27)
20.0±0.3
R1.8
(1.2)
19.1±0.3
21.9±0.3
3.5±0.3
1.45±0.15
1
1.2±0.1
• Radio-cassette
1.80±0.15
(12.5)
■ Applications
+0.10
0.25 –0.05 2.54
0.6
• Audio output : 3.1 W × 2 channel
• Built-in standby and muting circuit
• Built-in thermal shut down protection circuit
• Low pop noise during standby and mute ON/OFF
• No negative feedback pin
φ3.6
(10.0)
29.75±0.30
28.0±0.3
■ Features
HSIP012-P-0000A
■ Block Diagram
45 dB
45 dB
Over current
thermal
protection
circuit
Mute
12
11
10
VCC
GND
9
8
7
5
GND
4
3
2
1
6
Ripple
filter
STB
■ Pin Descriptions
Pin No.
Description
Pin No.
Description
1
Stand-by
7
ch.1 output
2
Muting
8
ch.1 bootstrap
3
ch.2 input
9
Output GND
4
ch.1 input
10
VCC
5
Input GND
11
ch.2 bootstrap
6
Ripple filter
12
ch.2 output
1
AN7124
ICs for Audio Common Use
■ Absolute Maximum Ratings
Parameter
Symbol
Rating
Unit
Supply voltage
VCC
24
V
Supply current
ICC
4.0
A
Power dissipation
PD
37.5
W
Operating ambient temperature
Topr
−25 to +75
°C
Storage temperature
Tstg
−55 to +150
°C
Symbol
Range
Unit
VCC
6.0 to 18.0
V
■ Recommended Operating Range
Parameter
Supply voltage
■ Electrical Characteristics at VCC = 12 V, RL = 3 Ω, f = 1 kHz, Ta = 25 °C
Parameter
Symbol
Conditions
Typ
Max
Unit
ICQ
VIN = 0 mV
12
19
26
mA
VNO
VIN = 0 mV,PG = 10 kΩ

0.27
0.5
mVrms
GV
VIN = 3 mV
43
45
47
dB
THD
VIN = 3 mV

0.05
0.5
%
Maximum output 1
PO1
THD = 10 %
4.3
5.0

W
Channel balance
CB
VIN = 3 mV
−1
0
1
dB
RR
RG = 0 Ω,VR = 280 mVrms,fR = 120 Hz
45
50

dB
ISTB
VIN = 0 mV

1
10
µA
Mut
VIN = 10 mV
60
80

dB
PO2
THD = 10 %,VCC = 9 V
2.5
3.0

W
CT
RG = 10 kΩ,VIN = 10 mV,f = 1 kHz
50
64

dB
Quiescent current
Output noise voltage
*1
Voltage gain
Total harmonic distortion
Ripple rejection
*1
Standby current
Muting effects
*1
Maximum output 2
Crosstalk
*1,*3
*3
*2
Note) *1 : With a filter band from 20 Hz to 20 kHz (12 dB/OCT) used.
*2 : With a filter band from 400 Hz to 30 kHz used.
*3 : Reference data for design.
2
Min
ICs for Audio Common Use
AN7124
1 µF
22 µF
33 µF
3.9 kΩ
1 000 µF
2.2 Ω
RL
3
Mute
12
11
10
1 000 µF
2.2 Ω
5 V(On)
STB
47 µF
47 µF
47 nF
VIN1
9
8
7
6
1 µF 100 µF
8.2 kΩ
(Off)5 V
(On)0 V
VIN2
5
4
3
2
1
■ Application Circuit Example
47 nF
1 000 µF
RL
3
VCC = 9 V/12 V
0 V(Off)
■ Characteristics Curve
PD  Ta
70
62.5 W
Power dissipation PD (W)
60
50
(1)
40
30
20.8 W
(2)
20
15.6 W
(3)
10
3.0 W
(4)
0
0
40
80
120
160
Ambient temperature Ta (°C)
1. TC = Ta (θj-c = 2 °C/W)
2. 20.83 W (θf = 4.0 °C/W)
With a 100 cm2 × 3 mm Al heat sink (black
colour coated) or a 200 cm 2 × 2 mm Al
heat sink (not lacquered)
3. 15.63 W (θf = 6.0 °C/W)
With a 100 cm2 × 2 mm Al heat sink(not
lacquered)
4. 3.0 W at Ta = 25 °C (θj-a = 42 °C/W)
Without heat sink
3
AN7124
ICs for Audio Common Use
■ Application Note
1.Voltage gain
The close loop gain of AN7124 is fixed at 45 dB(typ.)
GV = 20 log(
R1
84 Ω
R2
R1
R2
)
15 kΩ
2.Standby function
Standby is ON when Pin1 is set to "L". By applying a 5 V to the standby pin, transistor Q1 will be turned ON to
provide a constant current (I) for driving other parts of the circuit. The RC is to create a TIME CONSTANT for the
standby pulse during charging and discharging.
Off
R
5V
VCC
ZSTBY
Stb
Threshold voltage (at Pin1) :
1
I
C
ON<2.8 V<OFF
On
Q1
Impedance, ZSTBY ≈ 1 kHz
3.Muting
By controlling Pin2 from "H" to "L", the mute function is set from ON to OFF. When Pin2 is floating, DC ≈ 0.02
V. The threshold is set ≈ 2.8 V. The RC is to create a TIME CONSTANT for the mute pulse during charging and
discharging.
Bias
Off
R
5V
Mute
Threshold voltage (at Pin2) :
2
C
On
ZMUTE
10 % mute = 1.5 V
90 % mute = 2.8 V
Impedance, ZMUTE ∞ 45 kΩ
4
ICs for Audio Common Use
AN7124
■ Application Note (continued)
4.Oscillation
To prevent oscillation, it is advisable to use C (Zobel network capacitor). Using polyester film capacitor has small
characteristic fluctuation with temperature and the frequency.The resistor R connected in series with C is effective
for phase correction at high frequency, as a result, it improves the oscillation allowance.
1 000 µF
Pin7,12
C
47 nF
R
2.2 Ω
5.Bootstrap
The capacitor C connected between the output and bootstrap pin helps to increase the output dynamic range and
hence increases the output power of the IC.
pp
VCC
Pin8,11
47 µF
C
Pin7,12
5