OV7520 OV7576-A23A-DG OV7604 OV7604C7 OV-7604-C7 OV-7604-C7 32.768KHZ OV-7604-C7 32.768KHZ 20PPM TA QC OV-7604-C7 32.768KHZ 20PPM TB QC OV-7604-C7 ON BOARD 32.768K 20PPM TA QC OV-7604-C7-20PPM-TB-QA