STM32 SAR ADC Internal structure

The ADC in stm32x microcontrollers uses the SAR (successive approximation register) principle,

By which the conversion are performed in several steps.

The number of conversion steps is equal to the number of bits in the ADC converter.

Each step was driven by the ADC clock.

Each ADC is clock produces one bit from the result to output.

ADC internal design is a switched-capacitor type.

The following figures (Figure 1 to Figure 6) explain the principle of ADC operation.

The example given below shows only the first steps of approximation

But the process continues till the LSB is reached.

STM32 SAR ADC Internal structure