Im trying to develop a small DAQ system to measure 10 strain gages. Im thinking of interfacing it using analog multiplexers and one instrumentation amplifier, since it reduces both cost and space of the circuit. Using current excitation for the gages. Following figure shows the block diagram for 4 strain gages.
I want to know whether this arrangement degrades the accuracy of the reading. The second MUX is allocated for sensing. Its Rons are in series with IA inputs, (hence no affect as i guess). Does the Ron of MUXES affect the system performance ? Can any tell me about this ? or is there a better way of implementing this ?