593
I
2
C Bus (IIC)
Chapter 18
Preliminary User’s Manual U17566EE1V2UM00
18.5 I
2
C Bus Pin Functions
The serial clock pin (SCLn) and serial data bus pin (SDAn) are configured as
follows.
SCLn
This pin is used for serial clock input and output.
This pin is an N-ch open-drain output for both master and
slave devices. Input is Schmitt input.
SDAn
This pin is used for serial data input and output.
This pin is an N-ch open-drain output for both master and
slave devices. Input is Schmitt input.
Since outputs from the serial clock line and the serial data bus line are N-ch
open-drain outputs, an external pull-up resistor is required.
Figure 18-4
Pin configuration diagram
18.6 I
2
C Bus Definitions and Control Methods
The following section describes the I
2
C bus’s serial data communication format
and the signals used by the I
2
C bus. The transfer timing for the “start
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