The DS1200 serial RAM chip is a miniature read/write memory that can randomly access individual 8-bit strings (bytes) or sequentially access the entire 1024-bit contents (burst). Interface cost to a microprocessor is minimized by on-chip circuitry, which permits data transfers with only three signals: CLK, active-low RST, and DQ. Nonvolatility can be achieved by connecting a battery of 2V to 4V at the battery input VBAT. A load of 0.5µA should be used to size the external battery for the required data retention time. If nonvolatility is not required the VBAT pin should be grounded. Applications * Automatic System Setup * Calibrators * Computer Identification * Secure Personnel Areas * Software Authorization * Systems Access Control * Traveling Work Record * 1024 Bits of Read/Write Memory * Low Data Retention Current for Battery Backup Applications * Four Million Bits/Second Data Rate * Single-Byte or Multiple-Byte Data Transfer Capability * No Restrictions on the Number of Write Cycles * Low-Power CMOS Circuitry