5 SDA Handoff Delay After the Acknowledge

The same SDA handoff delay signal that is seen on the eighth falling clock pulse can also happen at the ninth falling clock pulse. This can occur when the I²C target device releases the SDA line after having control of it during an ACK. If the I²C controller does not regain control of the SDA line quick enough, then the SDA signal can be seen rising before falling again which could look like an SDA pulse. This is illustrated in Figure 5-1. This is also acceptable from an I²C-bus standard perspective as long as the clock line is low and the set up time of the data line is still being met.

Figure 5-1 SDA Handoff Delayed Pulldown After Ninth Clock Pulse