Two-channel Power Amplifier for Radio Cassette
Players (No Heat Sink Needed during 9 V Operation)
Overview
The LA4598 is a two-channel power IC that is intended for
use in portable audio equipment. Needing no heat sink during
9 V operation facilitates set design with a small footprint.
Functions
.
Thermal shutdown protector built in.
.
Standby switch built in.
Features
.
No heat sink needed during 9 V operation
.
P
O
= 2.9 W
2 (V
CC
= 9 V, R
L
= 3.2
, THD = 10%).
.
Less quiescent current. (V
CC
= 9 V, 20 mA, typ).
.
Operating voltage range: V
CC
op = 4.2 to 16 V.
Package Dimensions
unit : mm
3113-SIP14HZ
[LA4598]
SANYO : SIP14HZ
Specifications
Maximum Ratings
at Ta = 25 C
Parameter
Symbol
Conditions
Ratings
Unit
Maximum supply voltage
V
CC
max
18
V
Allowable power dissipation
Pd max*
No heat sink
3.6
W
Junction temperature
Tj max
+150
C
Operating temperature
Topr
20 to +75
C
Storage temperature
Tstg
40 to +150
C
* With Sanyo-recommended board (9.0 cm
8.5 cm
1.5 mm (thickness))
Allowable
power
dissipation,
Pd
max
-
W
Independent IC
With arbitrarily large heat
sink
Al heat sink tightening
torque 4kg.cm
With silicone grease
applied
Ambient temperature, Ta - C
With Sanyo-
recommended board
Ordering number: EN4087C
Monolithic Linear IC
LA4598
SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN
D3095HA/N1792TS(II) No.4087-1/9
Operating Conditions
at Ta = 25 C
Parameter
Symbol
Conditions
Ratings
Unit
Recommended supply voltage
V
CC
9
V
Recommended load resistance
R
L
3.2
Operating voltage range
V
CC
op
4.2 to 16.0
V
Operating Characteristics
at Ta = 25 C, V
CC
= 9 V, f = 1 kHz, Rg = 600
, R
L
= 3.2
Parameter
Symbol
Conditions
min
typ
max
unit
Quiescent current
I
CCO
10
20
40
mA
Voltage gain
VG
47
49
51
dB
Output power
P
O
1
THD = 10%
2.2
2.9
W
P
O
2
THD = 10%, R
L
= 4
2.3
W
Total harmonic distortion
THD
V
O
= 2 V
0.3
1.0
%
Input resistance
ri
20
30
k
Output noise voltage
V
NO1
Rg = 0, B.P.F = 20 Hz to 20 kHz
0.4
1.0
mV
V
NO2
Rg = 10 k
, B.P.F = 20 Hz to 20 kHz
0.6
2.0
mV
Ripple rejection ratio
Rr
Rg = 0, fr = 100 Hz, V
CC
r = 150 mV
40
50
dB
Channel separation
CH Sep
Rg = 10 k
, V
O
= 0 dB
45
55
dB
Standby current
Isd
10
A
Block Diagram
Sample Print Pattern
Unit (resistance:
, capacitance: F)
Copper-foiled side 85
90 mm
2
Input
amplifier
Predrive
amplifier
Power
amplifier
Bias circuit
Thermal shutdown
protector
Standby switch
Input
amplifier
Predrive
amplifier
Power
amplifier
ch1 Input
ch1 NF
Pre GND
D.C
ch2 Input
ch2 NF
ch1 BS
ch1 output
Power GND
V
CC
Standby
ch2 output
ch2 BS
LA4598
No.4087-2/9
Sample Application Circuit
Description of External Components
C
1
, C
8
: Bootstrap capacitors
These capacitors affect low-region output; if the capacitor value is reduced, the low-region output decreases. Therefore,
47 F or more is desirable.
C
2
, C
6
: Output capacitors
If the capacitor value is reduced, low-region roll-off frequency f
L
and low-region Po worsen.
C
3
, C
7
: Oscillation blocking capacitors
Mylar capacitor, which is excellent in temperature characteristics and frequency characteristics is used.
C
4
:
Power supply capacitor
The capacitor values depends on the power supply line loads (motor, and the like.) and transformer ripple component.
1000 F to 2200 F is recommended.
C
5
:
Standby capacitor
Pop noise reduction capacitor
C
9
, C
11
: Feedback capacitors
In addition to affecting low-region roll-off frequency f
L
, if the capacitor value is increased, the start-up time is extended.
C
10
:
Decoupling capacitor
This capacitor absorbs power supply ripples; 220 F is recommended.
R
1
, R
2
: Oscillation blocking resistors
The resistor value may be varied 3.3
to 1.0
.
Mylar capacitor
Unit (resistance:
, capacitance:F)
To large signal GND
Mylar capacitor
C + R can be added to the negative side of the output capacitor.
However, this is true only for a Sanyo-recommended board; for a set board, artwork must also be
considered.
LA4598
No.4087-3/9
T
otal
harmonic
distortion,
THD
-
%
Frequency, f - Hz
Current
drain,
I
CC
-A
Pd when VCC=12 V
Pd when 9 V
Output power, P
O
- W
Power
dissipation,
Pd
-
W
Output power, P
O
- W
Power
dissipation,
Pd
-
W
Current
drain,
I
CC
-A
Current
drain,
I
CC
-A
Output power, P
O
- W
Power
dissipation,
Pd
-
W
Quiescent
current,
I
CCO
-m
A
mA
Supply voltage, V
CC
- V
Output
power
,
P
O
-W
Supply voltage, V
CC
- V
LA4598
No.4087-4/9
Channel
separation
-
d
B
CH2 to CH1
leak
CH1 to CH2
leak
T
otal
harmonic
distortion,
THD
-
%
Frequency, f - Hz
Supply voltage, V
CC
- V
Response
-
d
B
Frequency, f - Hz
T
otal
harmonic
distortion,
THD
-
%
Output power, P
O
- W
Output
ripple
noise
voltage,
V
NOR
-m
V
Output
noise
voltage,
V
NO
-m
V
Supply voltage, V
CC
- V
Supply voltage, V
CC
- V
DIN Audio with
20 Hz to 20 kHz BPF
LA4598
No.4087-5/9
BTL Sample Application Circuit
Output
ripple
noise
voltage,
V
NOR
-m
V
Output
ripple
noise
voltage,
V
NOR
-m
V
Ripple frequency, f
R
- Hz
Power supply ripple, V
R
- mV
Unit (resistance:
, capacitance:F)
To large signal GND
Mylar capacitor
C + R can be added to the negative side of the output capacitor.
However, this is true only for a Sanyo-recommended board; for a set board, artwork must also be considered.
LA4598
No.4087-6/9
Current
drain,
I
CC
-A
Output power, P
O
- W
Power
dissipation,
Pd
-
W
Current
drain,
I
CC
-A
Output
power
,
P
O
-W
Power
dissipation,
Pd
-
W
Output power, P
O
- W
Supply voltage, V
CC
- V
Output power, P
O
- W
T
otal
harmonic
distortion,
THD
-
%
Frequency, f - Hz
Response
-
d
B
LA4598
No.4087-7/9
Features and Usage Notes
1.
VG can be lowered by adding an R
NF
' to the NF pins (pins 5 and 11).
Calculated as follows:
VG = 20log R
f
/(R
NF
+ R
NF
')
The IC contains R
f
= 20 k
, R
NF
= 62
.
However, the following must be noted:
a) If R
NF
' is added, the ripple bypass effect due to the NF capacitor will worsen, resulting in a worsening of ripple
rejection.
b) Oscillation stability requires, use at 40 dB or less to be avoided.
2.
Pin 9 is intended for standby. It is used in conjunction with power supply pin 4. However, it should be noted that when
power supply pin 9 and pin 4 are used for separate systems, the output power is affected by the pin 9 supply voltage.
3.
It is recommendable to use no input capacitor. However when rubbing noise generated by the volume control is offencive to
the ear, an input capacitor must be inserted.
4.
Extreme caution must be exercised when the IC is used in the vincity of the maximum ratings, since even a slight variation
in conditions may cause the maximum ratings to be exceeded, thereby leading to breakdown.
5.
When making the board, refer to the sample printed circuit pattern. No feedback loop must be formed between input and
output. Thick and short wiring is required so that no common resistance exists between the preamplifier GND and power
amplifier GND.
6.
Addition of components as shown below enables use without introducing an increased distortion at V
CC
of up to
approximately 4.5 V. A capacitor of 470 F is inserted against pop noise.
Proper Cares in Mounting a Radiator Fin
1.
The tightening torque should be in a range from 4 to 6 kg.cm.
2.
The spacing between the screw holes of the radiator fin must match the spacing between the screw holes of the IC. With case
outline dimensions L and R referred to, the screws must be tightened with the distance between them as close to each other
as possible.
3.
The screws to be used must have a head equivalent to the one of truss machine screw or binder machine screw defined by
JIS. Washers must also be used to protect the IC case.
4.
No foreign matter such as cutting particles should exist between heat sink and radiator fin. When applying grease on the
junction surface, it must be applied uniformly on the whole surface.
5.
IC lead pins should be soldered to the printed circuit board after the radiator fin is mounted on the IC.
LA4598
No.4087-8/9
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 December, 1995. Specifications and information herein are subject to change without notice.
LA4598
No.4087-9/9
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