That is another way of doing this.You do over voltage protection with a resistor in series with the input and two normal diodes connecting from the signal line to the +5V power supply line and the ground line.
This is a very good explanation - thanks. ADC data sheet says 10uA - so 100K works. I will put it parallel to zener:Then you add a resistor from the input to ground, just enough to drain the leakage current of the ADC input pin. Might be over 100K. Read your datasheet.
The zener does conduct slightly, reverse current. However, when it does, as you see in your results, the voltage across it is 5V, not 0V as when you have a very small current through a resistor. Your zener diode does not follow Ohm's law like a simple resistor.My though was that since zener conducts slightly (reverse current) it would make pin1 on P1 to be at ground level with nothing connected to P1.
|Thread starter||Similar threads||Forum||Replies||Date|
|Zener Diode Circuit Analysis||Homework Help||12|
|B||Zener diode_reverse bias||Homework Help||38|
|B||Zener diodes in series reverse biased||Analog & Mixed-Signal Design||3|
|P||Zener Failure Issue||Power Electronics||6|
|M||Max a zener can clamp||General Electronics Chat||14|
by Luke James
by John Koon