SLVSA67F February 2010 – April 2020 TPS62400-Q1 , TPS62402-Q1 , TPS62404-Q1 , TPS62405-Q1
UNLESS OTHERWISE NOTED, this document contains PRODUCTION DATA.
The device only applies the acknowledge condition if all of the following occurs:
In this case, the device turns on the internal ACKN-MOSFET and pulls the MODE/DATA pin low for the time tACKN, which is 520 μs maximum. The acknowledge condition is valid after an internal delay time tvalACK. This means the internal ACKN-MOSFET turns on after tvalACK, on detection of the last falling edge of the protocol. The master controller keeps the line low during this time.
The master device can detect the acknowledge condition with its input by releasing the MODE/DATA pin after tvalACK and reading back a 0.
In case of an invalid device address, or not-correctly-received protocol, application of a no-acknowledge condition does not occur; thus, the internal MOSFET does not turn on, and the external pullup resistor pulls the MODE/DATA pin high after tvalACK. One can use the MODE/DATA pin again after the acknowledge condition ends.
NOTE
The master device must have an open-drain output in order to request the acknowledge condition.
In case of a push-pull output stage, TI recommends using a series resistor in the MODE/DATA line to limit the current to 500 μA in case of an accidentally requested acknowledge, to protect the internal ACKN-MOSFET.