13

Daisy chaining

The ISO808A can be daisy-chained by connecting the MOSI port of the microcontroller to the SDI pin of the first

IC of the chain; the SDO pin of the first IC of the chain to the SDI pin of the second (and similarly for the next ICs

of chain); the SDO pin of the last IC of the chain to the MISO port of the microcontroller.

The tcycle(SS) (see Figure 7) must take into account the internal communication timing (frefresh and tWD): it is

recommended tcycle(SS) (max.) < 136 μs. The maximum number of ICs that can be daisy chained depends on the

SPI clock frequency set by the microcontroller.

Figure 28. Example of daisy-chaining connection

ISO808A, ISO808A-1

Daisy chaining

DS14170 - Rev 1

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