dear all
i am designing a simpel temperature based circuit in which i am using 8051 , 12 bit adc,opamp stage, and cd4051 for analog muxltiplexing of the gains.
i am trying to design a programmable gain amplifier.
now the problem is when i connect cd4051 with opamp the resistances (8) get added in parallel to each other and i am not able to select only one resistance.my opamp is running on 5 volts supply.and cd 4051 alos is running on 5 volts.
wht might be the error.