protection circuit with Zener 5,6V

Marcio's picture
Joined: Oct 19, 2017
protection circuit with Zener 5,6V
October 19, 2017 - 7:58pm

I have a circuit that has a 5V input, but i need make sure that when the voltage reaches 6 or 7V or more, the circuit keeps with 5,6 V! I already tried to put one Zener Diode with a resistance 1k attached to 5V line to GND, but the voltage reach more of 5,6V in my microcontroller.

any ideas how to solve this problem?

Thank you

B.Aswinth Raj's picture
Joined: Aug 16, 2016
Regulator solution
October 23, 2017 - 10:52am

Hi Marcio,

Using a Zener should have solved the issue, also note that zener is a low current regulator device. If zener did not work for you try using a Potential divider if our output load current is less.

Also why havent you used a Voltage regulator like 7805?

Elaborating more on the source of voltage and where you are using them would have helped me to do more justice to this question

Joined: Jan 19, 2018
zener diode usage
January 19, 2018 - 10:03pm

Frist up all check your Zener diode rating, it may have limit voltage to 5.6 V


Sjamie's picture
Joined: Feb 20, 2018
Use lower zener voltage
February 20, 2018 - 7:02pm

Hi marco,

Usually the voltage of a zener won't match in real live values. You should use lower than 5V, like 4.7V but you can even go lower as the microcontroller will still reed a one at say 3V.