STM32L071 and 5V tolerant I/O in analog mode for adc use

[kevin_delporte]

Hello everyone,

I have a question about 5V tolerant I/O in analog mode. When I look Figure 20. Basic structure of a 5-Volt tolerant I/O port bit in RM0377, i don't see the analog arrow as in figure 19.

Is it an error on figure or 5V tolerant I/O doesn't work in analog mode ?

Thanks for any response

[TDK]

Somewhere there is a note that pins in analog mode are not 5V tolerant. I will try to find it.

Edit: Can only find this:

And this, which says the analog switch is only closed when the ADC is activated. The pin will still be 5V tolerant if the ADC is inactive.

Solved: Are STM32L0 FT pins 5V tolerant in Analog mode whe... - STMicroelectronics Community

[kevin_delporte]

I see this note, but my question is : Do 5V Tolerant work in analog mode ? Because I don't see a link to analog mode in figure 20

[TDK]

> Do 5V Tolerant work in analog mode ?

No, they are not 5V tolerant when in analog mode and being used by the ADC.

[AScha.3]

Hi,

>about 5V tolerant I/O in analog mode.

Its just : only as digital input a pin can (FT_ pins) tolerate 0...5V signal. 

As soon as you use any other pin setting, output or analog, ist always limited to vss-vdd (or vdda), 0...3v3 typical.

The ADC itself anyway working on vssa - vdda , so nothing else possible as ADC-input.