IDQC3 is a crystal oscillator input receiver pad piece with a non-inverting, CMOS-level clock input. QO is the output to either the ODQFE20M or the ODQTE60M. PADM is the bond pad from the Xtal-in. Logic Symbol IDCQ3 QC P D QO PADM The Possible Logic Schematic Combinations QC E P QC D QO E QI X.