Why is the input impedance on Channel 0 of the KUSB-3108 different from the other channels? It appears to be in the 10k ohm range rather than 100M ohm like the other channels.

Product(s):

USB Modules: KUSB-3108,

Question:The input impedance on Channel 0 of the KUSB-3108 is different from the other channels.The input impedance on Analog Channel 0 appears to be in the 10k ohm range rather than 100M ohm.I presume this has something to do with the CJC circuitry.How can I get this channel to operate with a high input impedance?

 

Answer:The KUSB-3108 has the CJC input on CH 0. It can still be driven externally but the input impedance may be as low as 10K.If 100M ohm is needed on all channels, either KUSB-3102 or KUSB-3116 module, without a CJC, would be needed.

 

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