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4-6
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Chapter 4
PFI 0 and Digital Input Measurements
Choose a capacitor that has the following suggested characteristics:
•
AXL or RDL package
•
Tolerance of 20%
•
Maximum voltage of at least 25 V
Adding Components for Lowpass Digital Filtering on
Digital Trigger Input Signals
Using the circuit shown in Figure 4-8, you can use a two-component circuit to build a simple RC
filter with digital input. For PFI 0, add the resistor to position A and the capacitor to position B.
Refer to Figure 4-9 for the digital input channel pad configuration.
The SCB-68A ships with a surface mount 0
Ω
resistor in the A position. You
must
remove the
resistor to use the position.
Figure 4-9.
SCB-68A Circuit Diagram for Digital Trigger Input Lowpass Filter
45
11
44
S
C10
A
+
B
11
+
44
PFI 0
D GND