Philips TDA8944J User Manual

Page of 21
Philips Semiconductors
TDA8944J
2 x 7 W stereo BTL audio amplifier
Product specification
Rev. 02 — 14 February 2000
14 of 21
9397 750 06861
© Philips Electronics N.V. 2000. All rights reserved.
14.1.2
Power supply decoupling
Proper supply bypassing is critical for low-noise performance and high supply voltage
ripple rejection. The respective capacitor locations should be as close as possible to
the device and grounded to the power ground. Proper power supply decoupling also
prevents oscillations.
For suppressing higher frequency transients (spikes) on the supply line a capacitor
with low ESR – typical 100 nF – has to be placed as close as possible to the device.
For suppressing lower frequency noise and ripple signals, a large electrolytic
capacitor – e.g. 1000
µ
F or greater – must be placed close to the device.
The bypass capacitor on the SVR pin reduces the noise and ripple on the midrail
voltage. For good THD and noise performance a low ESR capacitor is recommended.
Fig 15. Printed-circuit board layout (single-sided); components view.
idth
MGL951
ON
MUTE
220 nF
100 nF
1.5 nF
1000 
µ
F
10 
µ
F
220 nF
1
17
+
IN2
IN2
+
IN1
IN1
+
OUT1
OUT1
+
OUT2
OUT2
+
VCC
GND
54 mm
56 mm