SFFS138 December   2021 TCAN1164-Q1

 

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Floating Pins

There are internal pull ups on critical terminals to place the device into known states if the terminal floats.

Table 5-6 Terminal Fail-Safe Biasing
TERMINAL PULL-UP or PULL-DOWN COMMENT
TXD Pull-up Weakly biases TXD toward recessive to prevent bus blockage or TXD DTO triggering
nCS Pull-up Weakly biases nCS high to prevent un-intended SPI communication
SCLK Pull-down Weakly biased to ground

The following sections provide the functional safety mechanisms that cover floating pins: