Chapter 2
SC-2070 Board
© National Instruments Corporation
2-13
SC-207X Series User Manual
resistors are 6.2 k
Ω
. The closest standard 1% resistors are 6.34 k
Ω
. Figure 2-11 shows both the
schematic and the component placement for a 50-kHz highpass filter placed on differential input
channel 1. If the input signal source is floating, a bias return resistor must be placed in the D position
(R10 in this case).
Note: Highpass filters generally exhibit poorer common-mode rejection characteristics than
lowpass filters because capacitors are in the series input paths. Capacitors have poorer
tolerances than resistors, and matching of the input impedances is crucial for good common-
mode rejection.
The SC-2070 board open component locations do not facilitate RC highpass filters with the MIO-16
board configured for single-ended inputs. Therefore, if the MIO-16 board is configured for single-
ended inputs, highpass filters must be built on the custom breadboard area.
+ Channel
- Channel
Input Schematic
To
Input
Multiplexer
+
-
E
F
G
Channel 1
Channel 9
R11
R8
R7
C3
R10
R12
(- in)
(+ in)
Component Positions
R9
0.001
µ
F Capacitor
0.001
µ
F
0.001
µ
F
6.34 k
Ω
Resistor
0.001
µ
F
0.001
µ
F
6.34 k
Ω
6.34 k
Ω
Figure 2-11. Highpass Filter on Differential Channel 1
Содержание SC-207 Series
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