The CY7C261, CY7C263, and CY7C264 are high-performance 8192-word by 8-bit CMOS PROMs. When deselected, the CY7C261 automatically powers down into a low-power standby mode. It is packaged in a 300-mil-wide package. The CY7C263 and CY7C264 are packaged in 300-mil-wide and 600-mil-wide packages respectively, and do not power down when deselected. The reprogrammable packages are equipped with an erasure window; when exposed to UV light, these PROMs are erased and can then be reprogrammed. The memory cells utilize proven EPROM floating-gate technology and byte-wide intelligent programming algorithms.