Application Note
18 of 63
V 1.2
2018-12-12
5 Output PMIC Controller/ IRPS5401
User guide with DB295 and DB296 demo boards
The OV_WARN_LIMIT is not a relative threshold. It is the absolute value set by the user. The user can cause an
OV_WARN flag by sending a VOUT_COMMAND greater than the OV_WARN_LIMIT threshold.
Fixed_ovp_thresh
Relative OVP
threshold
Regulation
TON_RISE
En
ab
le
Lo
w
VOUT_COMMAND < fixed_ovp_thresh
fixed_ovp_thresh
Enable Low
VOUT_COMMAND
TOFF_FALL
fixed_ovp_thresh
Relative OVP
threshold
Regulation
TON_RISE
En
ab
le
L
ow
VOUT_COMMAND > fixed_ovp_thresh
fixed_ovp_thresh
Enable Low
VOUT_COMMAND
1V
TOFF_FALL
Expected VOUT
Actual VOUT due to OVP
OVP declared with
Enable Low
Figure 24
VOUT_COMMAND
If VOUT_COMMAND = 0 V (or any value less than 0.25 V), the relative o V threshold will be used as VOUT
transitions down to 0 V. Then the fixed_ovp_thresh is used while waiting for a new VOUT_COMMAND.
4.8
Under Voltage Settings
Similar to OVP, the UV protection is based on thresholds that are relative to the VOUT_COMMAND value. There
are eight (8) relative threshold values from 50 mV to 400 mV (below VOUT) in 50 mV increments. The user sets
the relative threshold by sending a VOUT_UV_FAULT_LIMIT value that is less than the VOUT_COMMAND by the
required threshold. If the VOUT_COMMAND is 1 V, a VOUT_UV_FAULT_LIMIT of 0.6 V (or less) will cause the
relative UVP threshold to be 400 mV. If the VOUT_COMMAND is increased to 1.2 V, the relative threshold of 400
mV will cause a UV fault at 0.8 V. If the VOUT_COMMAND decreases VOUT to 0.7 V, the relative UVP threshold
will be reduced to 100 mV (COMMAND-FAULT_LIMIT). If the VOUT_COMMAND decreases VOUT to 0.6 V (or
