For my current project with own pcb I want to use an ATMEGA32U4 (s. attached screenshot). I want to use the USB-connection for programming and sometimes to transfer eeprom-data. Normally the circuit is powered via the Pololu 5V regulator. Before a USB-connection will be established the Vin of the Pololu regulator will be separated from the main power source. As the Pololu regulator does not have a reverse voltage protection I would use a (schottky) diode between Vout of the regulator and +5V from USB. As the diode creates a voltage drop I would put another diode between GND of the regulator and the circuit's GND to keep the voltage at 5V. Would it work like that?
Thanks for the answers in advance!
Sounds as if you mean not reverse voltage protection, but protection against back-feeding the regulator.
You need to clarify this and cite which regulator you mean and what information makes you think this would be a concern.
Paul__B:
Sounds as if you mean not reverse voltage protection, but protection against back-feeding the regulator.You need to clarify this and cite which regulator you mean and what information makes you think this would be a concern.
Oops, I mixed something up. I read in the regulator's description (https://www.flikto.de/products/pololu-5v-step-up-step-down-voltage-regulator-s7vf5) that it is not reverse voltage protected, and mixed this up with back-feeding.
I assume that I will not need a protection against back-feeding!?
Probably not, but it may require some further research. That page does not indicate what chip or circuit it uses, but a search for "buck-boost regulator" would probably find the most common one and lead to the answer.
Paul__B:
Probably not, but it may require some further research. That page does not indicate what chip or circuit it uses, but a search for "buck-boost regulator" would probably find the most common one and lead to the answer.
Thanks!