PANASONIC AN5278

ICs for Audio Common Use
AN5278
4.8 W × 1 (18 V, 8 Ω) Power Amplifier with
Volume and Tone Control
1.7
±0.25
5.6±0.25
22.3±0.3
9
8
7
6
5
4
3
2
1
3.75±0.25
0.5
±0.1
1.2
±0.25
7.1
±0.25
2.54
6.3
±0.3
1.7±0.25
+0.1
0.45 –0.05
• Few external components :
• No boucherot cells (output C, R)
• No bootstrap capacitors
• Built-in DC mute of input pin during power-OFF
• Operating voltage range 12 V to 26 V (18 V typ.)
5.8±0.25
1.5±0.25
15.0
18.3±0.25
19.9±0.1
■ Features
8.4±0.25
0.1±0.05
The AN5278 is a monolithic integrated circuit designed
for 4.8 W × 1 channel OTL (18 V, 8 Ω) output audio power
amplifier suitable for TV application.
φ3.3±0.1
φ2.65±0.1
Unit : mm
■ Overview
■ Applications
• TV
HSIP009-P-0000
■ Block Diagram
Pre
amp.
10 kΩ
AC
mute
300 Ω
9
VCC
8
Out
7
GND
6
NF
5
DC
mute
RF
4
Volume
Vol.
3
Tone
2
LF
In
1
Tone
10 kΩ
1
AN5278
ICs for Audio Common Use
■ Pin Descriptions
Pin No.
Description
1
Sound input
2
Low frequency input
3
Tone control
4
Volume control
5
Ripple filter
6
Negative feedback
7
GND
8
Sound output
9
VCC
■ Absolute Maximum Ratings
Parameter
Supply voltage
Symbol
Rating
Unit
VCC
35.0
V
ICC
2
A
PD
1.6
W
Topr
−20 to +70
°C
Tstg
−55 to +150
°C
*2
Supply current
Power dissipation
*3
Operating ambient temperature
Storage temperature
*1
*1
Note) *1 : Ta = 25 °C except operating ambient temperature and storage temperature.
*2 : Without input signal, VCC is up to 35 V.
*3 : Power dissipation of the package at Ta = 70 °C.
■ Recommended Operating Range
Parameter
Supply voltage
2
Symbol
Range
Unit
VCC
12 to 26
V
ICs for Audio Common Use
AN5278
■ Electrical Characteristics at VCC = 18 V, RL = 8 Ω, f = 1 kHz, Vol. = 5.0 V, Tone = 2.5 V, Ta = 25 °C
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
Quiescent current
ICQ
No input signal
Measure VCC current
20
27
48
mA
Voltage gain
GV
VO = 1 V[rms]
GV = 20 log (VO/VIN)
27
30
33
dB
Total harmonic distortion
THD
VO = 1 V[rms]
BPF : 400 Hz to 30 kHz

0.4
1.0
%
Max. output power
POmax
THD = 10 %, PO = VO2/RL
4.3
4.8

W
Max. output attenuation
Attmax
VO = 1 V[rms]
Vol. = max. → min.
Attmax = 20 log
[VO (Vol. = min.) / VO (Vol. = max.)]
−66
−69

dB
Tone variable range 1
∆GTC1 f = 15 kHz, VO = 1 V[rms]
∆GTC = 20 log
[VO (Tone = 5.0 V) / VO (Tone = 2.5 V)]
7
9

dB
Tone variable range 2
∆GTC2 f = 15 kHz, VO = 1 V[rms]
∆GTC = 20 log
[VO (Tone = 0 V) / VO (Tone = 2.5 V)]

−11
−9
dB
Min
Typ
Max
Unit
• Design reference data
Note) The characteristic values below are theoretical values for designing and not guaranteed.
Parameter
Symbol
Conditions
Input dynamic range
DRIN
VVOL = 1 V
vary VIN until output THD = 1 %
Output DC bias
VODC
No input signal
Measure Pin8 DC
Max. output power 1
POmax1
THD = 10 %, VCC = 18.4 V
PO = VO2/RL
5
W
Max. output power 2
POmax2
THD = 10 %, VCC = 26 V
PO = VO2/RL
9
W
4.5
7.9
8.3
V[rms]
8.7
V
3
AN5278
ICs for Audio Common Use
330 Ω
Line out
10 kΩ
Tone
10 µF
VCC 9
Out 8
GND 7
RF 5
100 µF
0.01 µF
NF 6
10 µF 6.2 kΩ
Vol. 4
33 µF
Tone 3
Input
LF 2
In 1
■ Application Circuit Example
18 V
1000 µF
470 µF
Speaker
8Ω
5V
5V
Volume
Micom
100 Ω
330 Ω
1 Audio det.
47 µF
■ Usage Notes
1) External heatsink is needed when used. External heatsink should be fixed to the chassis.
2) Fin of the IC can be connected to GND.
3) Please prevent output to VCC short, output to GND short and load short to GND.
4) The temperature protection circuit will operate at Tj around 150 °C. However, if the temperature decreases, the
protection circuit would automatically be deactivated and resume normal operation.
4
ICs for Audio Common Use
AN5278
■ Technical Information
1.Characteristic Curve Chart
• HSIP009-P-0000 Package power dissipation
PD  T a
11
4
10.4
10
1
2
9
3
8
Power dissipation PD (W)
Tjmax − Ta
Rth
No heat sink
5.5 × 5.0 cm2 A1 board
(t = 1 mm)
7.5 × 7.5 cm2 A1 board
(t = 1 mm)
Infinity heat sink
Pmax <
4
7
6.65
6
5
4.14 3
4
2
3.36
3
1
2.5
2
2.63
2.15
1.6
1
0.0
0
50
25
70 75
100
125
150
Ambient temperature Ta (°C)
• ASO
Area of Safe Operation
2
t = 100 ms
1
Ie (A)
0.5
0.2
0.1
0.05
0.02
0.01
1
2
5
10
20
35 50
100
VCB (V)
5
AN5278
ICs for Audio Common Use
■ Technical Information (continued)
2.Application Note
1) Gain setting and frequency response
The gain is fixed to be 30 dB by internal resistors. The frequency response is flat for the values of R1 = 6.2 kΩ, and
C2 = 0.01 µF, between pins 1 and 2 (other conditions : tone control voltage is set at 2.5 V, and volume control voltage
is set at 5 V).
Gain
In 1
LF 2
30 dB
10 µF
VIN
6.2 kΩ
R1
Frequency
C2
0.01 µF
The gain can be reduced by inserting a resistor Rf in series with the electrolytic capacitor at Pin6.
Voltage gain = 20 log [10 kΩ/(Rf + 300 Ω)]
Out 8
10 kΩ
NF 6
300 Ω
Rf
RL = 8 Ω
10 µF
Bass boost can be easily implemented by inserting a series connection of RC between Pin8 (output) and Pin6 (NF).
Example : Rb = 12 kΩ, Cb = 0.022 µF
Rf
6
Out 8
10 kΩ
NF 6
300 Ω
Cb
Rb
RL = 8 Ω
ICs for Audio Common Use
AN5278
■ Technical Information (continued)
2.Application Note (continued)
2) Tone characteristics
When the tone control voltage (VT, at Pin3) is changed from 2.5 V to 5 V, the high frequency gain is increased
gradually up by a max. of 9 dB. When VT is changed from 2.5 V to 0 V, the high frequency gain is decreased
gradually down by a max. of −11 dB.
By increasing the value of the capacitor at Pin2, the treble cut can be further decreased.
Tone = 5 V
+9 dB
Gain (dB)
30 dB
Tone = 2.5 V
−11 dB
Tone = 0 V
1
15
Frequency (kHz)
3) Volume characteristic
The volume characteristic is logarithmic type. When the volume control voltage (VV, at Pin4) is 5 V, the gain is at
max. (30 dB) ; that is, there is no attenuation. When VV is decreased, the gain is decreased at the same time. When
VV is 0 V, the gain is at its minimum ; that is, there is max. attenuation, −69 dB.
Attenuation (dB)
0
Tone = 2.5 V
−69
0
1
2
3
Voltage (V)
4
5
4) Dynamic range
The AN5278 has been designed, specially to have as large an input dynamic range as possible. The input D-range
is about 4.5 V[rms], or 12.7 V[p-p] (conditions of measurement : VCC = 18 V, adjust the gain downwards by
decreasing the volume control voltage).
7
AN5278
ICs for Audio Common Use
■ Technical Information (continued)
2.Application Note (continued)
5) Internal AC mute pulse (during power ON/OFF)
The start-up response of the AN5278 is designed to be as smooth as possible. During power ON and OFF, the AC
mute circuit turn on momentarily. The input signal and any external noise interference are being mute. The output
DC level follows the rise and fall time of RF pin.
Condition : VCC = 18 V, CRF = 100 µF, CNF = 10 µF, CVCC = 1000 µF.
VCC
Pin9
3.2 V
2.4 V
VRF
Pin5
3.6 V
3.6 V
2.8 V
Output
Pin8
310 ms
Internal line
mute pulse
660 ms
590 ms
100 ms
Line out
8
ICs for Audio Common Use
AN5278
■ Technical Information (continued)
2.Application Note (continued)
6) Internal DC mute pulse (during power OFF)
During power OFF, the decay response of the RF pin is being made use of internally, to generate an internal DC
mute pulse. The output DC level is made to fall quickly. As the output level falls, any transient noise that happens
prior to the input pin is effectively cut off from the IC. The residual electric charge in the large output capacitor (at
Pin8) is discharged into the IC internal path. By this manner, at the next start-up, the output will start from almost
0 V, and reduce the occurrence of shock noise.
Condition : VCC = 18 V, CRF = 100 µF, CNF = 10 µF, CVCC = 1000 µF.
Output
Pin8
Internal
DC mute
pulse
300 ms
7) Shock noise precaution
During power ON, to reduce the occurence of“Shock”noise, please be careful when selecting suitable capacitor
values for RF (Pin5) and NF (Pin6).
Recommendation : −
1. NF = 10 µF *
RF = 100 µF to 330 µF
* : Due to small NF capacitor, the low frequency cut-off is about 50 Hz.
2. NF = 22 µF *
RF = 220 µF to 330 µF
* : Due to larger RF capacitor, the start-up time is longer, about 1 second.
9