The integrated output
amplifier described in this article consists of little more than one
integrated circuit. It is intended especially for use in motor vehicles and other batteryoperated applications. Although it appears simple and hardly worth looking at, the amplifier can produce an appreciable
audio power output.
technical data
PropertiesHigh power output through Class-H operation
Low power dissipation during reproduction of music signals
Proof against short-circuits
Protection against excessive temperatures
Standby switch
No power-on or power-off clicks
Visible error indication
Measurement results (at Ub=14.4 V)
Supply voltage 8–18 V
Sensitivity 760 mV r.m.s.
Input impedance 70 kΩ
Power output 54 W r.m.s.
into 4 Ω (f=1 kHz; THD+N=1%)
Harmonic distortion (THD+N) at 1 W into 4 Ω: 0.046% (1 kHz)
0.29% (20 kHz)
at 35 W into 4 Ω: 0.12% (1 kHz)
0.7% (20 kHz)
Signal-to-noise ratio (with 1 W into 4 Ω) 88 dBA
Power bandwidth 7.5 Hz – 185 kHz (at 25 W into 4 Ω)
Quiescent current about 135 mA (‘on’)
COMPONENTS LIST
Resistors:
R1 = 1MΩ
R2 = 4kΩ7
R3 = 1kΩ
R4 = 100kΩ
Capacitors:
C1,C2 = 470nF
C3,C4 = 10μF 63V radial
C5,C6,C8 = 4700μF 25V radial
(18mm max. dia., raster 7.5 mm)
C7 = 100nF, raster 5 mm
Semiconductors:
D1 = high-efficiency-LED
IC1 = TDA1562Q (Philips)
Miscellaneous:
S1 = single-pole on/off switch
Four spade connectors, PCB mount
Heatsink for IC1 (Rth<2.5>
how to connect a kill switch to this circuit to connect it to an car sugges with a wiring diagram