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I have a 3.3 V microcontroller pin (not 5 V tolerant) with an external 10 kΩ pull-up resistor. By mistake, the external pull-up resistor was connected to 5 V. As I understand it, the only thing that protects the pin from burning is its protection diode.

If the pin is declared as input, the current path will be 5 V -> pull-up resistor -> pin -> protection diode -> 3.3 V and on the MCU pin there will be 3.3 V + Vdiode.

What is the current path when the pin is declared as a push-pull output and the output level is set to high? What is the voltage level on the microcontroller pin? What is the voltage level when the pin is set to low?

enter image description here

Microcontroller is STM32F103C6T6, and pin is PB5

I have a 3.3 V microcontroller pin (not 5 V tolerant) with an external 10 kΩ pull-up resistor. By mistake, the external pull-up resistor was connected to 5 V. As I understand it, the only thing that protects the pin from burning is its protection diode.

If the pin is declared as input, the current path will be 5 V -> pull-up resistor -> pin -> protection diode -> 3.3 V and on the MCU pin there will be 3.3 V + Vdiode.

What is the current path when the pin is declared as a push-pull output and the output level is set to high? What is the voltage level on the microcontroller pin? What is the voltage level when the pin is set to low?

enter image description here

I have a 3.3 V microcontroller pin (not 5 V tolerant) with an external 10 kΩ pull-up resistor. By mistake, the external pull-up resistor was connected to 5 V. As I understand it, the only thing that protects the pin from burning is its protection diode.

If the pin is declared as input, the current path will be 5 V -> pull-up resistor -> pin -> protection diode -> 3.3 V and on the MCU pin there will be 3.3 V + Vdiode.

What is the current path when the pin is declared as a push-pull output and the output level is set to high? What is the voltage level on the microcontroller pin? What is the voltage level when the pin is set to low?

enter image description here

Microcontroller is STM32F103C6T6, and pin is PB5

Tweeted twitter.com/StackElectronix/status/1579622820241641473
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Applying 5V5 V to 3V33.3 V output pins

I have a 3V33.3 V microcontroller pin (not 5V5 V tolerant) with an external 10k10 kΩ pull up-up resistor. By mistake, the external pull up-up resistor iswas connected to 5V5 V. As I understand it, the only thing that protects the pin from burning is its protection diode.

If the pin is declared as input, the current path will be 5V5 V -> pull-up resistor -> pin -> protection diode -> 3V33.3 V and on the MCU pin there will be 3V3+Vdiode3.3 V + Vdiode.

What is the current path when the pin is declared as a push pull-pull output and the output level is set to high? What is the voltage level on the microcontroller pin? What is the voltage level when the pin is set to low?

enter image description here

Applying 5V to 3V3 output pins

I have a 3V3 microcontroller pin (not 5V tolerant) with an external 10k pull up resistor. By mistake, the external pull up resistor is connected to 5V. As I understand it, the only thing that protects the pin from burning is its protection diode.

If the pin is declared as input, the current path will be 5V -> pull-up resistor -> pin -> protection diode -> 3V3 and on MCU pin will be 3V3+Vdiode.

What is the current path when the pin is declared as a push pull output and output level is set to high? What is voltage level on the microcontroller pin? What is the voltage level when the pin is set to low?

enter image description here

Applying 5 V to 3.3 V output pins

I have a 3.3 V microcontroller pin (not 5 V tolerant) with an external 10 kΩ pull-up resistor. By mistake, the external pull-up resistor was connected to 5 V. As I understand it, the only thing that protects the pin from burning is its protection diode.

If the pin is declared as input, the current path will be 5 V -> pull-up resistor -> pin -> protection diode -> 3.3 V and on the MCU pin there will be 3.3 V + Vdiode.

What is the current path when the pin is declared as a push-pull output and the output level is set to high? What is the voltage level on the microcontroller pin? What is the voltage level when the pin is set to low?

enter image description here

added 69 characters in body; edited title
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JRE
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Applying 5V voltage to 3V3 output pins

I have a 3V3 microcontroller pin (not 5V tolerant) with an external 10k pull up resistor. By mistake, the external pull up resistor is connected to 5V. As I understand it,the the only thing that protects the pin from burning is its protection diode. 

If the pin is declared as input, the current path will be 5V -> pull-up resistor -> pin -> protection diode -> 3V3 and on MCU pin will be 3V3+Vdiode. What

What is the current path when the pin is declared as a push pull output and output level is set to high? What is voltage level on MCUthe microcontroller pin? What is the voltage level when the pin is set to low?

enter image description here

Applying 5V voltage to 3V3 output pins

I have 3V3 microcontroller pin (not 5V tolerant) with external 10k pull up resistor. By mistake, external pull up resistor is connected to 5V. As I understand,the only thing that protects pin from burning is protection diode. If pin is declared as input, current path will be 5V -> pull-up resistor -> pin -> protection diode -> 3V3 and on MCU pin will be 3V3+Vdiode. What is current path when pin is declared as push pull output and output level is set to high? What is voltage level on MCU pin? What is voltage level when pin is set to low?

enter image description here

Applying 5V to 3V3 output pins

I have a 3V3 microcontroller pin (not 5V tolerant) with an external 10k pull up resistor. By mistake, the external pull up resistor is connected to 5V. As I understand it, the only thing that protects the pin from burning is its protection diode. 

If the pin is declared as input, the current path will be 5V -> pull-up resistor -> pin -> protection diode -> 3V3 and on MCU pin will be 3V3+Vdiode.

What is the current path when the pin is declared as a push pull output and output level is set to high? What is voltage level on the microcontroller pin? What is the voltage level when the pin is set to low?

enter image description here

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