4.3 Serial Data (SDA/IO)

The SDA pin is bidirectional for serial data transfer. This pin is open-drain driven and may be wired with any number of other open-drain or open-collector devices. An external pull-up resistor must be connected between SDA and V_CC, a nominal value of 4.7KΩ may be used. The value of this resistor and the system capacitance loading the SDA bus will determine the rise time of SDA. This rise time will determine the maximum frequency during read operations. Low-value pull-up resistors will allow higher frequency operations while drawing higher average power supply current.