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PCIE-1840 User Manual
Appendix A
S
pecifications
A.6
AI Input Bandwidth and Settling
Input bandwidth issue for ±20, ±10, ±4 input ranges with 1 M Ohm input impedance.
A.6.1
Tunable Capacitor for One-tenth Voltage Divider in 1Mohm
Figure A.3 PCIE-1840 one-tenth divider Circuit
PCIE-1840 provides tunable capacitors beside each BNC connector to help compen-
sate the input bandwidth of 20Vpp, 10Vpp, and 4Vpp input ranges with 1M Ohm input
impedance. With large 1M Ohm input impedance, any small parasitic capacitance
could seriously affect the input impedance. To compensate the loss, tunable capaci-
tors are added along the one-tenth divider. Users can get the better performance by
fine-tuning the tunable capacitor. Here are the figures to describe the issue.
Trim. Capacitor
Function (1M input impedance only)
TC400
Analog input channel 0 bandwidth compensation*
TC500
Analog input channel 1 bandwidth compensation*
TC600
Analog input channel 2 bandwidth compensation*
TC700
Analog input channel 3 bandwidth compensation*
*Only workable in 20 Vpp, 10 Vpp, 4 Vpp input range.
Summary of Contents for PCIE-1840
Page 1: ...User Manual PCIE 1840 4 ch 16Bit 125 MS s High Speed Data Acquisition PCI Express Card ...
Page 4: ...PCIE 1840 User Manual iv ...
Page 12: ...PCIE 1840 User Manual 6 ...
Page 13: ...Chapter 2 2 Installation ...
Page 18: ...PCIE 1840 User Manual 12 ...
Page 26: ...PCIE 1840 User Manual 20 ...
Page 27: ...Appendix A A Specifications ...
Page 35: ...Appendix B B Block Diagram ...