UTC-IC UTCTA7368P

UTC TA7368P
LINEAR INTEGRATED CIRCUIT
0.6W AUDIO POWER AMPLIFIER
DESCRIPTION
The UTC TA7368P is suitable for the audio power amplifier
of portable cassette tape recorder and radio.
FEATURES
*Very few external components( only three capacitors)
*Low quiescent current
*High voltage gain: Gv=40dB
SIP-9
BLOCK DIAGRAM
Vcc
2
9
Ripple
Rejection
Input
1
Output
7
RL
3
Negative
Feedback
UTC
4
Phase
5
Pre
GND
6
Power
GND
UNISONIC TECHNOLOGIES CO., LTD.
1
QW-R107-009,A
UTC TA7368P
LINEAR INTEGRATED CIRCUIT
ABSOLUTE MAXIMUN RATINGS (Ta=25°C)
SYMBOL
VALUE
Supply Voltage
PARAMETER
VCC
14
V
Power Dissipation
PD
900
mW
-20 ~ 75
°C
-55 ~ 150
°C
Operating Temperature
TOPR
Storage Temperature
TSTG
Note: Derated Ta>25°C, in the proportion of 7.2mW/°C
UNIT
ELECTRONIC CHARACTERISTICS(Ta=25°C, Vcc=6V, f=1kHz, Rg=600Ω,RL=4Ω, unless otherwise
specified)
PARAMETER
SYMBOL
TEST CONDITIONS
Quiescent Circuit
Current
ICCQ
Voltage Gain
GV
MIN
TYP
VCC=3V,Vin=0
5.5
VCC=6V,Vin=0
6.6
VCC=9V,Vin=0
7.5
Vin=0.5mVrms
37
40
VCC=3V,RL=4Ω,THD=10%
Output Power
Pout
Total Harmonic
UNIT
mA
43
dB
120
VCC=6V,RL=4Ω,THD=10%
500
VCC=6V,RL=8Ω,THD=10%
300
450
VCC=9V,RL=8Ω,THD=10%
800
1100
VCC=9V,RL=16Ω,THD=10%
450
610
THD
MAX
720
mW
Pout=100mW
0.3
1
%
0.5
mVrms
Distortion
Output Noise Voltage
Vno
Rg=10kΩ,BPF=20Hz~20kHz
0.2
Ripple Rejection
RR
fr=100Hz,Vr=0.3Vrms,Crip=0
25
dB
Input Resistance
Rin
27
kΩ
TERMINAL DC VOLTAGE
Pin No.
1
2
3
4
5
6
7
8
9
Value(V)
0
2.4
0.62
0.64
0
0
2.61
NC
6
PRECAUTION FOR APPLICATION
1. Input stage (Figure 1)
The input stage of power amplifier is comprised of a PNP differential pair( Q2 and Q3) preceded by a PNP emitter
follower(Q1) which allows DC referencing of the source signal to GND. This eliminates the need for an input coupling
capacitor. However, in case the brush noise of volume becomes a problem, provide serially a coupling capacitor to
the input side.
2. Adjustment of the voltage gain (figure 2)
The voltage gain is fixed at Gv=40dB by the resistors( R4 and R5) in IC. Its reduction is possible through adding Rf as
shown in Figure 2. In this case, the voltage gain is obtained by the following equation: Gv=20log(R5+R4+Rf)/(R4+Rf).
It is recommended to use this IC with the voltage gain of Gv=28dB or over.
UTC
UNISONIC TECHNOLOGIES CO., LTD.
2
QW-R107-009,A
UTC TA7368P
LINEAR INTEGRATED CIRCUIT
Pin 9
Q2
Q3
R5
1
Pin 7
R4
R4
Pin 1 Q1
2
3
Q4
Rf
Pin 3
R1
27¦¸
Crip
R5
D1
Pin 5
Figure 1
Figure
2
Figure 3
3. Ripple rejection (Figure 3)
Adding Crip, to the ripple terminal 2 as shown in Figure 3, the ripple rejection ratio is improved from -25dB to -45dB.
4. Power dissipation
Casre should be taken to use IC below maximum power dissipation because it may be over maximum rating
depending on operating condition.
Pd=900mW (Ta=25°C)
5. Phase-compensation
Small temperature coefficient and excellent frequency characteristics is needed by capacitor below:
*Oscillation preventing capacitor for power amplifier output
*Bypass capacitor for ripple filter
*Capacitor between Vcc and GND
TEST CIRCUIT
Vcc
100 µF
2
9
Ripple
Rejection
Input
1
27kΩ
470 µF
10kΩ
90Ω
3
UTC
RL
4
100 µF
Negative
Feedback
Output
7
Phase
5
6
Pre Power
GND GND
UNISONIC TECHNOLOGIES CO., LTD.
3
QW-R107-009,A