Power supply considerations and improvement of the PSRR TSH346
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3 Power supply considerations and improvement of the
PSRR
Correct power supply bypassing is very important to optimize performance in low and high-
frequency ranges. Bypass capacitors should be placed as close as possible to the IC pin
(pin 4) to improve high-frequency bypassing. A capacitor (C
LF
) greater than 10 µF is
necessary to improve the PSRR in low frequencies. For better quality bypassing, a capacitor
of 100 nF (C
HF
) can be added. C
HF
must be placed as close as possible to the IC pin, to
improve the noise supply rejection in the higher frequency ranges. A coil can be added in
order to better reject the noise from the supply and to prevent current peaks as much as
possible.
Figure 21. Circuit for power supply bypassing
+V
CC
C
LF
+
C
HF
TSH346
R
G
B
4
5
Coil
AM00824
Obsolete Product(s) - Obsolete Product(s)
