SCPA062 July 2021 TCA9517
Rise time accelerators are included into specialized I2C translators or buffers to help drive heavy capacitive loaded I2C buses. This allows the external pullup resistors to be large to lower voltage output lows (VoLs). If the rise time accelerator circuit is designed to trigger upon only a voltage threshold level, the SDA hand-off delay can accidentally trigger the rise time accelerators to turn on and cause contention between the high-side driver of the rise time accelerator and the I2C device trying to pull the SDA line low. The consequence of this could cause damage to the devices under contention. So for this reason, the SDA lines on an I2C bus should be monitored to see if the SDA handoff delay occurs. If the SDA handoff delay occurs then the I2C system should be thoroughly tested across temperature, loading conditions, and boards whenever devices with rise time accelerators must be included on the bus where handoff delays are seen.