EXHIBIT 21 MICROSEMI CORPORATION SUBSIDIARIES AS OF 10/01/00 NAME OF MICROSEMI CORPORATION ENTITY LOCATION - ------------------------------------ -------- BKC Semiconductors Incorporated Lawrence, Massachusetts Linfinity Microelectronics, Inc. Garden Grove, California Micro USPD, Inc. Watertown, Massachusetts Micro WaveSys, Inc. Los Angeles, California Microsemi Corp. - Colorado Broomfield, Colorado Microsemi Corp. - Scottsdale Scottsdale, Arizona Microsemi Microwave Products Lowell, Massachusetts Microsemi PPC, Inc. Riviera Beach, Florida Microsemi RF Products, Inc. Montgomeryville, Pennsylvania Microsemi Santa Ana Santa Ana, California Micro (Bermuda), Ltd. Ennis, Ireland Microsemi (H.K.) Ltd. Shatin, N.T., Hong Kong Semcon Electronics Pvt. Ltd. Mumbai, India