adc

hello;
i m implementing temerature display on lcd.

i m using c8051f020 ic which has inbuilt adc.

i m using 4051 mux for selection of temperature from various sources (eg:temperature of bath, jar etc).
output of mux is given to adc of microcontroller through amplifier.

my code of selection of mux is working fine, i can see waveforms on scope.

i select the mux and give delay and after that i read adc.

delay given is 64msec. my output (display on lcd) is correct with 1 mux working at a time.

but when all mux are working simultaneously that time output is not as expected.

i tried to reduce as well as increase the delay but the output is still incorrect

i m using total 4 mux of 4051.

selection of the mux is done through port pin of microcontroller, and my selection is correct because output is correct with one mux working at a time.

problem is with all mux working together.

pls, guide me
thank u all