Need help with ADC of Esp8266 and 4051 mux

Thread Starter


Joined Nov 24, 2013
I am working on a Smart Energy Meter and I need to read 2 values on one ADC pin of Esp8266. So for this purpose i am using 4051 Mux. I am using Op amp as differential amplifier to measure 220v ac and ACS712 Arduino Module to Measure Current. The problem is that when i connect circuit of Differential Amplifier with Mux the Voltage drops to Zero. I used 2n2222 bjt in Common Collector configuration and got output as near to .5v but now ADC don't read it correctly. It's value doesn't change even if i change current at ACS712 or voltage at ADC after common emitter bjt. But Serial Monitor value don't change and keep fluctuation between 300 to 600. Can anyone help.
Thank you