Did some research thought I would share:
I know it's good practice to put reverse voltage protection diode on your regulator.. but is it always required?
According to Infineon if there is a PNP pass transistor it would limit the reverse current and therefore not always needed. if you can dissipate the heat and working at lower voltages you might be ok without reverse protection. Remember that thermal protection will not work in reverse polarity situations.
https://www.infineon.com/cms/en/pro...lator/Voltage-Regulator-Reverse-Polarity.html
For this AZ1117 5V - it looks like there is an NPN pass transistor and needs some sort of reverse polarity protection such as a diode, polarized connectors or permanent wiring that won't allow this to happen or risk being toast...
https://static6.arrow.com/aropdfconversion/82d5a41dde8764b091e2d8c0ea5ee766f168f1d/az1117c.pdf
Block Diagram
I know it's good practice to put reverse voltage protection diode on your regulator.. but is it always required?
According to Infineon if there is a PNP pass transistor it would limit the reverse current and therefore not always needed. if you can dissipate the heat and working at lower voltages you might be ok without reverse protection. Remember that thermal protection will not work in reverse polarity situations.
https://www.infineon.com/cms/en/pro...lator/Voltage-Regulator-Reverse-Polarity.html
For this AZ1117 5V - it looks like there is an NPN pass transistor and needs some sort of reverse polarity protection such as a diode, polarized connectors or permanent wiring that won't allow this to happen or risk being toast...
https://static6.arrow.com/aropdfconversion/82d5a41dde8764b091e2d8c0ea5ee766f168f1d/az1117c.pdf
Block Diagram
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