The Microchip Technology Inc. 24C01A/02A/04A is a 1K/2K/4K bit Electrically Erasable PROM. The device is organized as shown, with a standard two wire serial interface. Advanced CMOS technology allows a signif icant reduction in power over NMOS serial devices. A special feature in the 24C02A and 24C04A provides hardware write protection for the upper half of the block. The 24C01A and 24C02A have a page write capability of two bytes and the 24C04A has a page length of eight bytes. Up to eight 24C01A or 24C02A devices and up to four 24C04A devices may be connected to the same two wire bus.