bt829bkrf ETC-unknow, bt829bkrf Datasheet - Page 84

• Manufacturer Part Number: bt829bkrf
• Description: Video Streamii Decoders
• Manufacturer: ETC-unknow

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3.0 PC Board Layout Considerations
3.1 Ground Planes
3.1.1 Power Planes
The power plane area should encompass all Bt829B power pins, voltage reference
circuitry, power supply bypass circuitry for the Bt829B, analog input traces, any
input amplifiers, and all the digital signal traces leading to the Bt829B.
The layout for the power plane should be set up so the two planes are at the same
electrical potential, but they should be isolated from each other in the areas sur-
rounding the chip. The return path for the current should be through the digital
plane. This is the same layout as the ground plane (Figure 3-1). When using a reg-
ulator, circuitry must be included to ensure proper power sequencing. Figure 3-2
illustrates this circuitry layout.
Figure 3-2. Optional Regulator Circuitry
The Bt829B has digital power (VDD) and analog power (VAA and VPOS).
System Power
(+12 V)
Suggested Part Numbers:
Regulator
D829BDSA
In
GND
Ground
Texas Instruments
Out
(+5 V)
VAA, VDD
Diodes must handle
the current requirements
of the Bt829B and the
peripheral circuitry.
A78 MO5M
VideoStream II Decoders
System Power
Bt829B/827B
(+5 V)