2.3 W 2-Channel AF Power Amplifier
Features
.
Built-in 2 channels enabling use in stereo and bridge
amplifier applications.
.
High output: 2.3 W/channel, V
CC
= 9 V, R
L
= 4
, and
4.7 W/bridge, R
L
= 8
.
.
Minimum number of external parts required : 9 pcs. min.
(Stereo/bridge).
.
Small pop noise at the time of power supply ON/OFF due to
built-in muting circuit.
.
Good ripple rejection ratio due to built-in ripple filter.
.
Soft tone at the time of output saturation.
.
Good channel separation.
.
Voltage gain fixed at 45 dB (Bridge: 51 dB). Variable
voltage gain available with external resistor added.
.
Easy to design radiator fin.
Package Dimensions
unit : mm
3022A-DIP12F
[LA4182]
SANYO : DIP12F
Note) In general applications, heat generated in this package
can be radiated through the Cu-foiled area of the printed
circuit board, but since power dissipation Pd may be
increased depending on the supply voltage and load
conditions, it is recommended to use a fin additionally.
Specifications
Maximum Ratings
at Ta = 25C
Parameter
Symbol
Conditions
Ratings
Unit
Maximum supply voltage
V
CC
max
With signal
11
V
Quiescent
15
V
Allowable power dissipation
Pd max
With printed circuit board
(Refer to Pd-Ta characteristics)
4
W
Operating temperature
Topr
-20 to +75
C
Storage temperature
Tstg
-55 to +150
C
Recommended Operating Conditions
at Ta = 25C
Parameter
Symbol
Conditions
Ratings
Unit
Supply voltage
V
CC
9
V
Load resitance
R
L
Stereo
4 to 8
Bridge
8
Ordering number: EN742G
Monolithic Linear IC
LA4182
SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN
41596HA(II)/O207KI/2146KI/4025KI/O291KI,TS No.742-1/9
Operating Characteristics
at Ta = 25C, V
CC
= 9 V, f = 1 kHz, R
L
= 4
, Rg = 600
, (
): 8
,
See specified Test Circuit.
Parameter
Symbol
Conditions
min
typ
max
Unit
Quiescent current
I
CCO
Stereo
Stereo
40
55
mA
Voltage gain
VG
Closed loop, V
IN
= -45 dB
Stereo
43
45
47
dB
Closed loop, VIN = -45 dB
Bridge
49
51
53
dB
Voltage gain difference
VG
Stereo
1
dB
Output power
P
O
THD = 10%
Stereo
1.7
2.3
(1.3)
W
THD = 10%
Bridge
(4.7)
W
Total harmonic distortion
THD
P
O
= 250 mW
Stereo
0.3
1.5
%
P
O
= 250 mW
Bridge
0.5
%
Input resistance
r
i
21
30
k
Output noise voltage
V
NO
Rg = 0
Stereo
0.3
1.0
mV
Rg = 10 k
Stereo
0.5
2.0
mV
Ripple rejection ratio
R
r
Rg = 0, V
R
= 150 mV
Stereo
40
46
dB
Channel separation
CHsep
Rg = 10 k
, V
O
= 0 dB
Stereo
40
55
dB
Pin Assignment and Equivalent Circuit
Allowable
power
dissipation,
Pd
max
-
W
Cu plate (fin 1)
Fe plate
(fin 1)
Fe Plate
(fin 2)
Recommended
printed circuit
board only
Cu-foiled area
reduced board
IC only
Ambient temperature, Ta - C
Shock
noise
rejecter
Input
amp 1
Output
amp 1
Ripple filter
Input
amp 2
Output
amp 2
Unit (resistance:
)
LA4182
No.742 -2/9
Sample Application Circuit 1 : Stereo
Sample Application Circuit 2 : Bridge
(Mylar)
(Mylar)
Unit (capacitance: F)
Example of printed pattern (bottom view) for use in stereo, bridge amplifier applications : 60
80 mm
2
Unit (capacitance: F)
Stereo
Bridge
(Mylar)
(Mylar)
Unit (capacitance: F)
LA4182
No.742 -3/5
Description of External Parts
C1(C2)
Feedback capacitor
The low cutoff frequency depends on this capacitor. If the capacity is increased,
the starting time is delayed.
C3(C4)
Bootstrap capacitor
If the capacity is decreased, the output at low frequencies goes lower.
C5(C6)
Oscillation preventing capacitor
Polyester film capacitor, being good in temperature characteristic, frequency
characteristic, is used. If an aluminum electrolytic capacitor or ceramic capacitor
is used, oscillation may occur at low temperatures.
C7(C8)
Output capacitor
The low cutoff frequency depends on this capacitor. In order for the low
frequency characteristic in the bridge amplifier to be equal to that in the stereo
amplifier application, the capacity must be doubled.
C9
Decoupling capacitor
Used for the ripple filter. Since the rejection effect is saturated at a certain
capacity, it is meaningless to increase the capacity more than needed. This
capacitor, being also used for the time constant of the muting circuit, affects the
starting time.
C10
Power source capacitor
Application Circuit
1.
Voltage gain adjustment
k Stereo
The voltage gain depends on built-in resistors R1 (R2),
R3 (R4) as follows :
VG = 20log
R3 (R4)
R1 (R2)
[dB]
If the IC is used at a voltage gain less than this, the
following equation with Rf added applies.
VG = 20log
R3 (R4)
R1 (R2) + Rf
[dB]
where R1 (R2) = 50
, R3 (R4) = 10 k
k Bridge
The above shows the bridge amplifier configuration, where ch.1 operates as a noninverting amplifier and ch.2 as an inverting
amplifier. The output of ch.1 is divided with R5, R6 and led to pin 1 and then input to ch.2.
Since the attenuation degree (R5/R6) of ch. 1 output and the amplification degree (R4/R2 + R6) of ch. 2 are fixed at an equal
value, the ch.2 output is in opposite phase with the ch. 1 output. Therefore, the total voltage gain gets apparently 6 dB higher
than the voltage gain of ch.1 alone and is determined by the following equation.
VG = 20log
R3
R1
+ 6 [dB]
If the IC is used at a voltage gain less than this, the following equation with Rf added applies.
VG = 20log
R3
R1 + Rf
+ 6 [dB]
LA4182
No.742 -4/9
2.
Proper cares in using IC
.
If the IC is used in the vicinity of the maximum rating, even a slight variation in conditions may cause the maximum rating to
be exceeded, thereby leading to a breakdown. Allow an ample margin of variation for supply voltage, etc. and use the IC in the
range where the maximum rating is not exceeded.
.
Pin-to-pin short
If the supply voltage is applied when the space between pins is shorted, a breakdown or deterioration may occur. When
mounting the IC on the board of applying the supply voltage, make sure that the space between pins is not shorted with solder,
etc.
.
Load short
If the IC is used with the load shorted for a long time, a breakdown or deterioration may occur. Be sure not to short the load.
.
When the IC is used in radios or radio-cassette tape recorders, keep a good distance between IC and bar antenna.
.
When making the board, refer to the example of printed circuit pattern.
Proper cares in operating a set with LA4182 incorporated
When a set with the LA4182 incorporated is operated from AC power supply, a momentary drop in supply voltage is caused by
the transformer regulation, etc. at the time of turning ON the motor with the circuit shown below. In this case, if ripple noise is
generated from the speaker or headphone, take the following actions.
1.
Connect a diode (rectifier diode of average rectified current I
O
= 100 to 200 mA) across pins 6 and 12 of the LA4182 so that
the voltage at pin 6 can follow the supply voltage regulation. In the steady state, this diode is cut off.
2.
Increase the capacity of the power source capacitor so that the supply voltage regulation can be minimized.
Radiation design
.
Since the DIP 12-pin package is so designed as to be able to radiate heat through the Cu-foiled area of printed circuit board
under normal operating conditions, make the Cu-foilled area near the fin of IC as large as possible when designing the printed
circuit board.
.
By providing the Cu-foiled area covered by the broken line as shown in the above-mentioned example of printed circuit pattern,
a rather satisfactory radiation is enabled. (Refer to the Pd max-Ta characteristics.)
.
Since the power dissipation (Pd) goes higher depending on the conditions of supply voltage and load, it is recommended to use
a fin together with the printed circuit board.
.
The following equations are rule-of-thumb guides for Pd (for stereo). For AC power supply, it is desirable to measure with the
transformer of each individual set. In the bridge amplifier application, calculation should be made with 1/2 of the load used.
(1) DC power supply
Pd max =
V
CC
2
2
R
L
+ I
CCO
v V
CC
(For stereo)
Unit (capacitance: F)
LA4182
No.742 -5/9
(2) AC power supply
Pd max =
V
CC
(Pd)
2
2
R
L
+ I
CCO
v V
CC
(Pd) (For stereo)
V
CC
2
: Quiescent supply voltage
V
CC
(Pd)
: Supply voltage at max. output,
V
CC
1
: Supply voltage at max. output
r
: Voltage regulation,
V
CC
2 - V
CC
1
V
CC
1
I
CCO
: Quiescent current
Example of fin mounting
The fin is formed into such a shape as to be able to radiate heat from the plastic fin area of IC and the fin as shown below and is
soldered to the printed circuit board. For the fin size, refer to the Pd max-Ta characteristics. The desirable material is copper or
iron which is solderable. It is recommended to apply silicone grease, etc. to the plastic area of IC in order to minimize the thermal
resistance.
[Stereo Application]
Printed circuit board
Example of fin-mounting
Fin
Output
power
,
P
O
-W
Input voltage, V
IN
- mV
Response
-
d
B
Frequency, f - Hz
LA4182
No.742 -6/9
V
oltage
gain,
VG
-
d
B
Frequency, f - Hz
T
otal
harmonic
distortion,
THD
-
%
Output power, P
O
- W
T
otal
harmonic
distortion,
THD
-
%
Output power, P
O
- W
T
otal
harmonic
distortion,
THD
-
%
Frequency, f - Hz
T
otal
harmonic
distortion,
THD
-
%
Frequency, f - Hz
Channel
separation,
CHsep
-
d
B
Amp. 2
1
Amp. 1
2
Frequenccy, f - Hz
Output
ripple
voltage,
V
r
p
-
m
V
Output
noise
voltage
V
NO
-m
V
VCC (Ripple) = 150 mVrms/f = 50 Hz
Signal source resistance, Rg -
Power
dissipation,
Pd
(Stereo)
-
W
Using specified fin
Output power, P
O
- W
LA4182
No.742 -7/9
Power
dissipation,
Pd
(Stereo)
-
W
Using specified fin
Output power, P
O
- W
Current
drain,
I
CC
-m
A
Output power, P
O
- W
Output
power
,
P
O
-W
Supply voltage, V
CC
- V
Quiescent
current,
I
CCO
-
m
A
(Stereo)
Supply voltage, V
CC
- V
Midpoint
voltage,
V
N
-V
Output
voltage,
V
N
(Midpoint
voltage)
-
V
Ambient temperature, Ta - C
Quiescent
current,
I
CCO
-m
A
Ambient temperature, Ta - C
[Bridge Application]
Output
power
,
P
O
-W
Input voltage, V
IN
- mV
Response
-
d
B
Frequency, f - Hz
LA4182
No.742 -8/9
No products described or contained herein are intended for use in surgical implants, life-support systems, aerospace equipment,
nuclear power control systems, vehicles, disaster/crime-prevention equipment and the like, the failure of which may directly or
indirectly cause injury, death or property loss.
Anyone purchasing any products described or contained herein for an above-mentioned use shall:
1
Accept full responsibility and indemnify and defend SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors
and all their officers and employees, jointly and severally, against any and all claims and litigation and all damages, cost and
expenses associated with such use:
2
Not impose any responsibility for any fault or negligence which may be cited in any such claim or litigation on SANYO
ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors or any of their officers and employees jointly or severally.
Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume
production. SANYO believes information herein is accurate and reliable, but no guarantees are made or implied regarding its use
or any infringements of intellectual property rights or other rights of third parties.
This catalog provides information as of April, 1996. Specifications and information herein are subject to change without notice.
T
otal
harmonic
distortion,
THD
-
%
Output power, P
O
- W
T
otal
harmonic
distortion,
THD
-
%
Output power, P
O
- W
T
otal
harmonic
distortion,
THD
-
%
Frequency, f - Hz
Power
dissipation,
Pd
-
W
Output power, P
O
- W
Using specified fin
Output
power
,
P
O
-W
Supply voltage, V
CC
- V
Current
drain,
I
CC
-m
A
Output power, P
O
- W
LA4182
No.742 -9/9
PDF 
ZIP