SA7267
2-CH AUDIO POWER AMPLIFIER(20W X 2)
DESCRIPTION
The SA7267 is a monolithic integrated circuit in HSIP package,
intended for use as dual audio frequency class AB amplifier.
FEATURES
* Wide supply voltage range(up to
±20V
)
* Split supply operation.
* High output power: 20W+20W @ THD=10%, R
L
=4 , Vs=±15V
* Mute/stand-by function.
* Few external components.
* Short circuit protection.
* Thermal shutdown protection.
HSIP-15
HSIP-11
APPLICATIONS
* Hi-Fi music centers
* Stereo TV sets
ORDERING INFORMATION
Part No.
SA7267
SA7267A
Package
HSIP-11
HSIP-15
BLOCK DIAGRAM
Note: Figures for the SA7267.
HANGZHOU SILAN MICROELECTRONICS CO.,LTD
Http: www.silan.com.cn
REV:1.1
2006.05.25
Page 1 of 11
SA7267
ABSOLUTE MAXIMUM RATING
Characteristics
DC Supply Voltage
Output Peak Current (Internally Limited)
Power Dissipation Tcase=70°C
Storage And Junction Temperature
Supply voltage to guarantee short-circuit
protection
Thermal Resistance From Junction To
Case (Max)
normal.
Symbol
V
s
I
o
P
tot
T
stg
, T
j
V
s(sc)
R
th(j-c)
Rating
40
3
40
-40~+150
±18(*)
2
Unit
V
A
W
°C
V
°C/W
(*)Maximum supply voltage to guarantee short-circuit to
±
Vs is
±18V,
and to GND short-circuit protection is
ELECTRICAL CHARACTERISTICS
(Refer to the test circuit, Vs=±15V; R
L
=4Ω; Rs=50Ω; Gv=30dB; f=1KHz; T
amb
=25°C, unless otherwise specified.)
Characteristics
Supply Range
Total Quiescent Current
Input Offset Voltage
In-phase Input Bias Current
Output Power
Symbol
V
s
I
q
V
os
I
b
THD=10%;
P
o
R
L
=4Ω;
R
L
=8Ω
RL=8Ω; Po=1W; f=1KHz
R
L
=8Ω;
P
o
=0.1~5W;
Total Harmonic Distortion
THD
f=100Hz~15KHz
R
L
=4Ω; P
o
=1W; f=1KHz
R
L
=4Ω;
P
o
=0.1~5W;
f=100Hz~15KHz
Cross Talk
Slew Rate
Open Loop Voltage Gain
Total Noise Input Voltage
Input Resistance
Supply Voltage Rejection (each
channel)
CT
SR
GV
e
N
Ri
SVR
Fr=100Hz; V
ripple
=0.5Vrms
A curve
f=20Hz~22KHz
15
f=1KHz
f=10KHz
50
6.5
70
60
8
80
3
4
20
60
8
dB
dB
V/µs
dB
µV
µV
KΩ
dB
(To be continued)
Test conditions
Min.
±5
Typ.
50
Max.
±20
100
+25
Unit
V
mA
mV
nA
W
W
%
-25
500
20
12.5
0.03
0.7
%
0.02
1
%
%
HANGZHOU SILAN MICROELECTRONICS CO.,LTD
Http: www.silan.com.cn
REV:1.1
2006.05.25
Page 2 of 11
SA7267
(Continued)
Characteristics
Thermal
Shut-down
Junction
Temperature
Mute Function [ref: +Vs]
Mute /Play Threshold
Mute Attenuation
Stand-by Function [ref: +Vs]
Stand-by /Mute Threshold
Stand-by Attenuation
Quiescent Current @ Stand-by
Symbol
Tj
Test conditions
Min.
Typ.
145
Max.
Unit
°C
VT
MUTE
AM
VT
ST-BY
A
ST-BY
Iq
ST-BY
-7
60
-3.5
-6
70
-2.5
110
3
-5
V
dB
-1.5
6
V
dB
mA
PIN CONFIGURATION
PIN DESCRIPTION
Pin No.
HSIP-11
1
2
3
4
5
HSIP-15
2
3
5
6
7
Pin Name
-Vs
OUT 1
+Vs
OUT 2
MUTE / ST-BY
I/O
--
O
--
O
I
Pin Description
Negative power
Output1
Positive power
Output2
Mute /stand-by function
(To be continued)
HANGZHOU SILAN MICROELECTRONICS CO.,LTD
Http: www.silan.com.cn
REV:1.1
2006.05.25
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SA7267
(Continued)
Pin No.
HSIP-11
6
7
8
9
10
11
HSIP-15
8
9
10
12
13
14
1,4,11,15
Pin Name
-Vs
IN+(2)
IN-(2)
GND
IN-(1)
IN+(1)
NC
I/O
--
I
I
--
I
I
--
Pin Description
Negative power
Inverting Input 2
Non inverting input 2
Ground
Non inverting input 1
Inverting input 1
Not connected
FUNCTION DESCRIPTION
MUTE STAND-BY FUNCTION
The MUTE/ST-BY controls the amplifier status by two different thresholds, referred to +Vs.
Ø
Ø
Ø
When MUTE/ST-BY higher than +Vs - 2.5V, the amplifier is in Stand-by mode and the final stage
generators are off.
When MUTE/ST-BY is between +Vs - 2.5V and +Vs- 6V, the final stage current generators are
switched on and the amplifier is in mute mode
When MUTE/ST-BY is lower than +Vs - 6V, the amplifier is in play mode.
Power Dissipation and Heat Sinking
The SA7267 must always be operated with a heat sink. In order to determine the appropriate heat sink for a
given application, the power dissipation of the SA7267 in that application must be known. When the load is a
resistor, the maximum average power of the IC is approximately:
P
D(MAX)
=Vs
2
/π
2
R
L
+PQ
Where VS is the total power supply voltage across the SA7267, RL is the load resistance and PQ is the
quiescent power dissipation of the amplifier. The above equation is only an approximation which assumes an
“
ideal”class B output stage and constant power dissipation in all other parts of the circuit. The curves of “
Power
Dissipation vs. Power Output”give a better representation of the behavior of the SA7267 with various power
supply voltages and resistors. As an example, if the SA7267 is operated on a ±15V power supply with a
resistance of 4Ω, it can develop up to 24.5W of internal power dissipation. If the die temperature is to remain
below 150°C for ambient temperatures up to 50°C, the total junction-to-ambient thermal resistance must be less
than:
(150°C 50°C)/24.5W
4.1°C/W
Using Rth(j-c) = 2°C /W, the sum of the case-to-heat-sink interface thermal resistance and the heat-sink-to-
ambient thermal resistance must be less than 2.1°C/W. The case-to-heat-sink thermal resistance of the HSIP-11
package varies with the mounting method used. A metal-to-metal interface will be about 1°C /W if use the thermal
resistance, and about 1.2°C /W if not.
If a mica insulator is used, the thermal resistance will be about 1.6°C /W lubricated and 3.4°C /W dry. For this
example, we assume a lubricated mica insulator between the SA7267 and the heat sink. The heat sink thermal
resistance must then be less than:
4.1°C/W-2°C/W-1.6°C/W
0.5°C/W
HANGZHOU SILAN MICROELECTRONICS CO.,LTD
Http: www.silan.com.cn
REV:1.1
2006.05.25
Page 4 of 11
SA7267
This is a rather large heat sink and may not be practical in some applications. If a smaller heat sink is required
for reasons of size or cost, the heat sink can be isolated from the chassis so the mica washer is not needed. This
will change the required heat sink to a 1.1°C /W unit if the case-to-heat-sink interface is lubricated.
The thermal requirements can become more difficult when an amplifier is driving a reactive load. For a given
magnitude of load impedance, a higher degree of reactance will cause a higher level of power dissipation within
the amplifier. As a general rule, the power dissipation of an amplifier driving a 60º reactive load (usually
considered to be a worst-case loudspeaker load) will be roughly that of the same amplifier driving the resistive
part of that load. For example, a loudspeaker may at some frequency have impedance with a magnitude of 8Ω
and a phase angle of 60º. The real part of this load will then be 4Ω, and the amplifier power dissipation will
roughly follow the curve of power dissipation with a 4Ω resistor.
TYPICAL APPLICATION CIRCUIT IN SPLIT SUPPLY
Note: Figures for the SA7267.
HANGZHOU SILAN MICROELECTRONICS CO.,LTD
Http: www.silan.com.cn
REV:1.1
2006.05.25
Page 5 of 11
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