ZHCS616E March 2012 – February 2017 TCA9554
PRODUCTION DATA.
When power (from 0 V) is applied to VCC, an internal power-on reset holds the TCA9554 in a reset condition until VCC has reached VPORR. At that point, the reset condition is released and the TCA9554 registers and SMBus/I2C state machine initializes to their default states. After that, VCC must be lowered to below VPORF and then back up to the operating voltage for a power-on reset cycle.