The TPS3803G15 device has a fixed-sense threshold voltage VIT set by an internal voltage divider, whereas the TPS3803-01 has an adjustable SENSE input that can be configured by two external resistors. In addition to the fixed sense threshold monitored at VDD, the TPS3805 devices provide a second adjustable SENSE input. RESET is asserted in case any of the two voltages drops below VIT.