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DESIGN NOTE
Lay-Out Procedure for R.F. and High Performance
Analog Designs
1. Group parts by function block. This includes signal and power,
isolation, coupling, and by-pass.
2. Estimate function block lay-out sizes, then sketch entire board
block diagram, taking into account signal flow and potential
interaction between blocks.
3. Power and signal lines must not run through blocks, but around
them. This isolates power and clock noise.
4. Each individual block must be isolated from power distribution
busses. This precludes use of a single power plane as in digital
boards.
5. Quality of ground determines common mode noise susceptibility. By
far the best and simplest way to get good ground is with a buried
contiguous ground layer as in a four layer board. Use jumper wires
to reduce cutting up of ground layer where neccessary.
6. To route individual blocks use parts location and orientation to
effect:
a. shortest possible trace length
b. most direct signal path
c. isolation of signal input from output. (Considering both related
parts & traces)
8. A rationally laid out board will "read" just like a rationally
drawn schematic.
Call or write for more information,
or to place your order!
Felton Electronic
Design
email: feltondesign@yahoo.com
write us:
Chuck Felton KD0ZS
Felton Electronic Design
1115 S. Greeley Hwy
Cheyenne, Wy. 82007
307-634-5858
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