The BR93LC46F and BR93LL46FV are CMOS serial input / output-type memory circuits (EEPROMs) that can be programmed electrically. Each is configured of 64 words× 16 bits (1,024 bits), and each word can be accessed individually and data read from it and written to it. Operation control is performed using five types of commands. The commands, addresses, and data are input through the DI pin under the control of the CS and SK pins. In a write operation, the internal status signal (READY or BUSY) can be output from the DO pin.