57.9.1.1 Digital Filter

The TWI features digital filters on data and clock lines that can be configured by software via the TWI Filter register (FLEX_TWI_FILTR).

In Standard, Fast and Fast Plus modes, the digital filter must be enabled (FILT=1) and a pulse width threshold defined (THRES > 0).

The field THRES must be set according to the peripheral clock to suppress spikes below 50 ns. The recommended value is calculated using the formula:

THRES > 50 ns/t_{peripheral_clock(ns)}