The CY74FCT16823T and the CY74FCT162823T 18-bit bus interface registers are designed for use in high-speed, low-power systems needing wide registers and parity. 18-bit operation is achieved by connecting the control lines of the two 9-bit registers. Flow-through pinout and small shrink packaging aids in simplifying board layout. The outputs are designed with a power-off disable feature to allow live insertion of boards.