Internal RC oscillator calibration

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DocID027266 Rev 2

2.5

Calibration process performance

2.5.1

Duration of the calibration process

The duration of the calibration process depends on:

1.

2.

3.

the number of measured frequencies during the calibration process “number of steps”.

Once the peripherals are configured and ready (mainly the LSE oscillator), the duration of

the calibration process is approximated by:

If the calibration process is run with a minimum frequency error for HSI16 oscillator

(HSI16_CalibrateMinError()), the number of steps is equal to 32. If the LSE oscillator

prescaler = 32768/8 = 4096 Hz) and the selected number of measured periods is 10, the

calibration consumes approximately:

duration = (2 x 11 x 32) / 4096 = 172 ms