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TDA7494
10W AMPLIFIER WITH DC VOLUME CONTROL
10W OUTPUT POWER RL = 8Ω,
@ THD = 10% V
CC
= 28V
ST-BY AND MUTE FUNCTIONS
LINEAR VOLUME CONTROL DC COUPLED
WITH POWER OP AMPLIFIER
NO BOUCHEROT CELL
NO ST-BY RC INPUT NETWORK
SIGNAL LINE OUTPUT BEFORE VOLUME
CONTROLLING AND MUTING
3 SWITCHABLE VOLTAGE CONTROLLED
INPUT PINS
SINGLE SUPPLY RANGING UP TO 35V
SHORT CIRCUIT PROTECTION
THERMAL OVERLOAD PROTECTION
INTERNALLY FIXED GAIN
SOFT CLIPPING
LOW TURN-ON TURN-OFF POP NOIS E
MULTIWATT 15 PACKAGE
BLOCK AND APPLICATION DIAGRAM
MULTIPOWER BI50II TECHNOLOGY
Multiwatt15
ORDERING NUMBER:
DESCRIPTION
The TDA7494 10W is class AB power amplifier
assembled in the @Multiwatt 15 package, specially designed for high quality sound, TV applications.
Features of the TDA7494 include volume control,
3 switchable inputs, Stand-by and mute functions.
TDA7494
3 x
470nF
IN 1
IN 2
IN 3
PWR GND
SGN GND
February 1997
5
6
1
15
8
D95AU414D
100K
2
SW CTL
SW
1
3
243 7910
MONITOR
OUT
100K
300nF
VOL PWR
2K
VOL CTL
300nF
SVR
MUTE/STBY
PROTECTIONS
STAND-BY
470µF
10K 1µF
13 +V
14
MUTE
CC
470µF
OUT
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TDA7494
ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Value Unit
V
S
V
IN
P
tot
T
amb
, T
T
stg
, V
V
2
(1) Operation between -20 to 85 °C guaranteed by correlation with 0 to 70°C.
PIN CONNECTION
DC Supply Voltage 35 V
Maximum Input Voltage 8 Vpp
Total Power Dissipation (Tamb = 70°C) 16 W
Ambient Operating Temperature Range (1) -20 to +85 °C
Storage and Junction Temperature -40 to 150 °C
j
Volume CTRL DC voltage 7 V
3
D95AU415A
PWR GND
OUT
+V
CC
N.C.
N.C.
MUTE
STAND-BY
SGN GND
SVR
IN 2
IN 1
MONITOR OUT
VOLUME CONTROL
SW CTL
IN 3
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
THERMAL DATA
Symbol Parameter Value Unit
R
th j-case
R
th j-amb
ELECTRICAL CHARACTERISTICS
= 25°C; unless otherwise specified.)
T
amb
Symbol Parameter Test Condition Min. Typ. Max. Unit
V
S
I
q
DCV
OS
V
O
P
O
Thermal Resistance Junction-case Typ = 3.8 Max = 4.8 °C/W
Thermal Resistance Junction-ambient max 35 °C/W
(Refer to the test circuit, V
= 21V, RL = 8Ω; Rg = 50Ω;
S
Supply Voltage Range 11 35 V
Total Quiescent Current 22 50 mA
Output DC Offset Referred to
No Input Signal -400 400 mV
SVR Potential
Quiescent Output Voltage VS = 28V 14 V
Output Power THD = 10%; VCC = 28V, RL = 8Ω
THD = 1%; V
CC
= 28V
THD = 10%; VCC = 21V,
THD = 1%; V
THD = 10%; V
THD = 1%; V
= 21V,
CC
= 21V, RL = 4Ω
CC
= 21V,
CC
THD = 10%; VCC = 18V,
THD = 1%; V
THD = 10%; V
THD = 1%; V
= 18V
CC
= 18V, RL = 8Ω
CC
= 18V
CC
8
6
5
3.5
5
3.9
4.5
3.5
3.5
2.5
10
8
5.5
4
7.5
5.5
6
4.5
3.75
2.85
W
W
W
W
W
W
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TDA7494
ELECTRICAL CHARACTERISTICS
(continued)
Symbol Parameter Test Condition Min. Typ. Max. Unit
THD Total Harmonic Distortion P
I
G
A
MinVol
peak
T
V
G
vLine
op
in
V
Output Peak Current (internally limited) 1.4 1.9 A
Operating Temperature 0 70 °C
Input Signal 2.8 Vrms
Closed Loop Gain Vol Ctrl > 4.5V 24.5 26 27.5 dB
Monitor Out Gain R
Attenuation at Min Volume Vol Ctrl < 0.5V 80 dB
= 1W; f = 1KHz; Gv = 26dB 0.4 %
O
LOAD Mon
= ∞ -3 -1.5 0 dB
BW 0.6 MHz
e
N
Total Output Noise f = 20Hz to 22KHz
350 700 µV
Play, max volume
f = 20Hz to 22KHz
60 100 µV
Play, max attenuation
f = 20Hz to 22KHz
30 50 µV
Mute
SR Slew Rate 5 8 V/µs
R
i
R
Mon
R
load Mon
SVR Supply Voltage Rejection f = 1kHz; max volume
T
M
T
s
V
ST-BY
V
MUTE
Input Resistance 22.5 30 KΩ
Monitor Output Resistance 1.4 2 3 KΩ
Monitor Output Load 30 KΩ
36 43 dB
C
= 470µA; V
SVR
f = 1kHz; max attenuation
C
= 470µA; V
SVR
RIP
RIP
= 1V
= 1V
RMS
60 73 dB
RMS
Thermal Muting 150 °C
Thermal Shut-down 160 °C
Stand-by threshold 2.3 2.5 2.7 V
Mute Threshold 2.3 2.5 2.7 V
Sel #1 Control Voltage Input #1 selected 0 1 V
Sel #2 Control Voltage Input #2 selected 2.3 2.7 V
Sel #3 Control Voltage Input #3 selected 4 5 V
I
qST-BY
A
MUTE
I
stbyBIAS
Quiescent Current @ Stand-by 0.6 1 mA
Mute Attenuation 60 75 dB
Stand-by bias current Stand by on; V
V
= 5V;
MUTE
ST-BY
= 5V;
80 150 µA
Play or Mute 2 20 µA
I
muteBIAS
Mute bias current Mute 1.5 10 µA
Play 0.5 5 µA
I
switchBIAS
Switch bias current Input #1 selected -0.5 5 µA
Input #2 selected 1 10 µA
Input #3 selected 1.5 20 µA
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TDA7494
Figure 1:
+5V
R1
3.3K
R2
3.3K
Figure 2:
Test and Application Circuit.
MONITOR
OUT
213
IN 1
IN 2
IN 3
C3 470nF
C4 470nF
C5 470nF
S1
4
JMP1
TP1
4
5
6
1
R3 100K
300nF
C6
SGN GND
P.C.B. and component layout.
13 +V
SW
1
2
3
82
+5V
VOL
P1
50K
LOG
R4
100K
5K
VOL PWR
TP2
C10 470µF
14
MUTE/STBY
PROTECTIONS
37910
SVR
C7
300nF
C8
470µF
STAND-
BY
R5
10K
S3S2
15
MUTE
GND
C9
1µF
+5V
+5V
D96AU492B
C2
0.1µF
OUT
PGND
C1
1000µF
GND
CC
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