vicky29
Member level 4
adc input current limiting
hi,
i have designed a very simple circuit. in which a small voltage from a sensor is givcen to OPAMP--->current limiting resistor (with a zener diode)---->ADC---->uC----->LCD, as shown in figure. But as i chnage the value of current limiting resistor the voltage changes on the adc input pin (i.e. across the resistor) why s it happening so, and what value should i choose for this resistor.
Please help me.
hi,
i have designed a very simple circuit. in which a small voltage from a sensor is givcen to OPAMP--->current limiting resistor (with a zener diode)---->ADC---->uC----->LCD, as shown in figure. But as i chnage the value of current limiting resistor the voltage changes on the adc input pin (i.e. across the resistor) why s it happening so, and what value should i choose for this resistor.
Please help me.