Figure 9-1
shows an application in which the TCAL9539-Q1 can be
used.
A. Device address configured as 1110100 for this example.
B. P00, P02, and P03 are configured as outputs.
C. P01
and P04 to P017 are configured as inputs.
D. Resistors are required for inputs (on P port) that may float. If a driver to an
input will never let the input float, a resistor is not needed. Outputs (in the
P port) do not need pullup resistors.