TSH346 Datasheet, PDF (8/18 Pages) STMicroelectronics – Triple video buffer/filter for HD video applications

Power supply considerations and improvement of the PSRR
TSH346
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
+VCC
Coil
C_LF
+
C_HF
4
R
G
TSH346
B
5
AM00824
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