sta339bw STMicroelectronics, sta339bw Datasheet - Page 71

• Manufacturer Part Number: sta339bw
• Description: 2.1-channel High-efficiency Digital Audio System
• Manufacturer: STMicroelectronics

STA339BW
7
7.1
7.2
Application
Application scheme for power supplies
Here in
supply decoupling. Particular care has to be taken with the layout of the PCB. In particular
the 3.3 Ω resistors on the digital supplies (VDD_DIG) have to be placed as close as possible
to the device. This helps to prevent unwanted oscillation in the digital part of the device due
to the inductive tracks of the PCB. The same rule also applies to all the decoulpling
capacitors in order to limit spikes on all the supplies.
Figure 22. Application diagram
PLL filter
It is recommended to use the above scheme and values for the PLL filter to achieve the best
performance from the device in general applications. Note that the ground of this filter circuit
has to be connected to the ground of the PLL without any resistive path.
Concerning the component values, remember that the greater is the filter bandwidth, the
less is the lock time but the higher is the PLL output jitter.
Figure 22
below is the typical application diagram for STA339BW showing the power
Doc ID 15251 Rev 4
Application
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