74F521SCIC COMPARATOR IDENTITY 8B 20SOIC|FAIRCHILD SEMICONDUCTOR|Lead free|RoHS Compliant SN74F521DW SN74F521DWG4 74F521SCXIC COMPARATOR IDENTITY 8B 20SOIC|FAIRCHILD SEMICONDUCTOR|Lead free|RoHS Compliant SN74F521DWR SN74F521DWR