LA4728
Ordering number : EN
*
5716
2-Channel BTL Power Amplifier (35 W+35 W)
with Standby Switch for Car Stereos
Preliminary
Monolithic Linear IC
SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters
TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN
Overview
The LA4728 is a BTL two-channel power IC for car
audios developed in pursuit of excellent sound quality.
Low-region frequency characteristics have been improved
through the use of a new NF capacitorless circuit, and
crosstalk which causes "muddy" sound has been reduced
by improving both circuit and pattern layout. As a result
the LA4728 provides powerful bass and clear treble.
Features
High power: supports total output of 35 W+35 W. [EIAJ
power] (V
CC
=14.4 V, THD=30 %, R
L
=4
)
Less pop noise.
Designed for excellent sound quality.
(f
L
<10 Hz, f
H
=130 kHz)
Any rise time settable by an external capacitor.
Standby switch circuit on chip. (microcontroller support-
ed)
Various protectors on chip.
(output-to-ground short/ output-to-V
CC
short/ load
short/ overvoltage/ thermal shutdown circuit)
The LA4728 is pin-compatible with the LA4725.
Specifications
Maximum Ratings
at Ta = 25 C
Recommended Conditions
at Ta = 25 C
Package Dimensions
unit: mm
3113A-SIP14HZ
[LA4728]
SANYO: SIP14HZ
Parameter
Symbol
Conditions
Ratings
Unit
Maximum supply voltage
V
CC
max
18
V
Surge supply voltage
V
CC
surge f
0.2 s, single giant pulse
50
V
Maximum output current
I
O
peak
Per channel
3.5
A
Allowable power disspation
Pd max
With arbitrarily large heat sink
32
W
Operating temperature
Topr
35 to +85
C
Storage temperature
Tstg
40 to +150
C
Parameter
Symbol
Conditions
Ratings
Unit
Recommended supply voltage
V
CC
13.2
V
Operating voltage range
V
CC
op
Range where Pd max is not exceeded
9 to 16
V
Recommended load resistance
R
L
op
4
32497RM(KOTO) No.5716-1/3
LA4728
No.5716-2/3
Operating Characteristics
Ta = 25 C, V
CC
= 13.2 V, R
L
= 4 k
, f = 1 kHz, Rg = 600
Parameter
Symbol
Conditions
Ratings
Unit
min
typ
max
Quiescent current
I
CCO
Rg=0
70
125
250
mA
Standby current
I
ST
10
60
A
Voltage gain
VG
38
40
42
dB
Total harmonic distortion
THD
P
O
=1 W
0.06
0.2
%
Output power
P
O1
R
L
=4
, THD=10 %, V
CC
=13.2 V
16
20
W
P
O2
R
L
=4
, THD=10 %, V
CC
=14.4 V
25
W
P
O3
R
L
=4
, THD=30 %, V
CC
=14.4 V
35
W
Output offset voltage
V
N offset
Rg=0
300
+300
mV
Output noise voltage
V
NO
Rg=0, B.P.F.=20 Hz to 20 kHz
0.1
0.5
mVrms
Ripple rejection ratio
SVRR
Rg=0, f
R
=100 Hz, V
R
=0 dBm
40
50
dB
Channel separation
Chsep
Rg=10 k
, V
O
=0 dBm
50
60
dB
Input resistance
Ri
21
30
39
k
Standby pin applied voltage
Vst
Amp on, applied through 10 k
2.5
V
CC
V
20
0
20
40
140
160
60
80
100
120
0
3.1
5
10
10.4
13.9
15
20
20.8
30
32
25
35
Ambient temperature, Ta -- C
Allowable power dissipation, Pd max -- W
Pd max -- Ta
f=3C/W
Arbitrarily large heat sink
No fin
f=4C/W
f=7C/W
f=10C/W
jc=2.0C/W
LA4728
No.5716-3/3
Block Diagram and Sample Application Circuit
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 lose.
Anyone purchasing any products described or contained herein for an above-mentioned use shall:
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:
Not impose any responsibilty 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 guarant-
eed 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 March, 1997. Specifications and information herein are subject to
change without notice.
1
2
4
3
11
+
+
++
+
+
IN
Predriver
Power
13
+
12
Predriver
Power
C6
C5
VCC
2200
F
0.1
F
C7 0.1
F
R2
2.2
R3
2.2
OUT1
OUT1
RL
4
Load short
protector
(Polyester film
capacitor)
Overvoltage/
surge protector
Output pin-to-GND
short protector
Output pin-to-VCC
short protector
Thermal
shutdown
Standby
SW
BIAS
circuit
Ripple
filter
Pop noise
prevention
circuit
VCC
6
5
8
+
IN
Predriver
Power
9
+
10
Predriver
Power
C8 0.1
F
C9 0.1
F
R4
2.2
R5
2.2
OUT2
OUT2
RL
4
* *
* *
* *
* *
* *
Load short
protector
Power
GND2
Output pin-to-GND
short protector
Output pin-to-VCC
short protector
+
7
14
C1
2.2
F/6V
IN2
C4
2.2
F/6V
R1
10k
ON
OFF
+5V
33
F/6V
0.47
F/6V
C3
C10
100
F/16V
A07431
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