The Microchip Technology Inc. 24AA174 is a cascadable 16K bit Electrically Erasable PROM. The device is organized as eight blocks of 256 x 8-bit memory with a 2-wire serial interface and provides a specially addressed OTP (one-time programmable) 16 byte security block. Low voltage design permits operation down to 1.8 volts (end-of-life voltage for most popular battery technologies) with standby and active currents of only 5 μA and 1 mA respectively. The 24AA174 also has a page-write capability for up to 16 bytes of data. The 24AA174 is available in the standard 8-pin DIP and 8-lead surface mount SOIC packages. The three select pins, A0, A1, and A2, function as chip select inputs and allow up to eight devices to share a common bus, for up to 128K bits total system EEPROM.