After the device has completed the
optional inrush period (if enabled) the device will enter the steady operation. In this
operation, the overcurrent protection is provided by the immediate shutdown overcurrent
protection (I
OCP) and I2T protection (if enabled). The I
OCP is an
overcurrent protection function that immediately turns off the channel if the output
current exceeds I
OCP threshold that is set by the ILIMIT_SET_CHx [3:0] bits.
The I
OCP function can not be disabled and is always active in the steady
state operation while the device is enabled. The I2T protection provides a programmable
fuse protection that is based on a defined time-current curve. The intent of the I2T
protection is to match the behavior of a melting fuse. The time-current curve of the I2T
protection can be set through the NOM_CUR_CHx [2:0] bits and I2T_TRIP_CHx [3:0] bits.
The ISWCL_CHx [1:0] and I
OCP also help to define the time-current curve for
the I2T protection. The I
OCP and I2T protection (if enabled) are active in
the ACTIVE state and the LIMP_HOME state if the channel is in the steady state operation
after the inrush period.
The next
sections describes the I2T protection and the IOCP
protection.