SLVS503F November 2003 – February 2020 TPS2490 , TPS2491
PRODUCTION DATA.
This open-drain output is intended to interface to downstream DC/DC converters or monitoring circuits. PG goes open drain (high voltage with a pullup) after VDS of Q1 has fallen to about 1.25 V and a 9-ms deglitch time period has elapsed. PG is false (low or low resistance to ground) whenever VDS of Q1 has not been less than 1.25 V, VDS of Q1 is above 2.7 V, or UVLO is active. Both VDS rising and falling are deglitched while entering UVLO sets PG low immediately. PG can also be viewed as having an input and output voltage monitor function. The 9-ms deglitch circuit operates to filter short events that could cause PG to go inactive (low) such as a momentary overload or input voltage step. VPG voltage can be greater than VVCC because it’s ESD protection is only with respect to ground.