Download
Download

Download Manuals, Datasheets, Software and more:

DOWNLOAD TYPE
MODEL or KEYWORD

When acquiring data from one analog input channel with my KUSB module the data looks good, however, when acquiring more than one channel the data looks corrupt, especially when using a high gain. Why is this occurring?

Question :

When acquiring data from one analog input channel with my KUSB module the data looks good, however, when acquiring more than one channel the data looks corrupt, especially when using a high gain. Why is this occurring?

Answer :

Product(s):

USB Modules: KUSB-3100 Series: KUSB-3102, KUSB-3108, KUSB-3116,


Question:I get good readings when acquiring from one channel using either the KUSB-3102, KUSB-3108, or KUSB-3116. However, when acquiring more than one channel the data is corrupt, especially when using a high gain. Why is this occurring?

 


Answer:These modules have high impedance inputs (100M ohm).If your signals are coming from a high impedance source, they will not have time to settle out when doing a channel scan.The settling time increases when a high gain is applied.As a remedy, use instrumentation amplifiers between the inputs and our module. Analog Devices part #AD623 is a proven resolution.

 


 Copyright 2003, Keithley Instruments, Inc.


This FAQ Applies to:

No product series

Product:

FAQ ID 71641

View all FAQs »