A 4160-bit C4D serial memory

A 4160-bit serial memory chip has been designed, fabricated, and tested using as the basic memory cell the conductively connected charge-coupled device (CCD) or C4D. The chip includes an inverting regenerator every 65 bits and a reading tap every 130 bits. Also on-chip is a recirculating amplifier which senses the charge packet as it reaches the end of the register and feeds it back to the input. This means that once data has been written onto the chip, it will be retained as long as the regenerator supply and the two clocks are on. The chip has two multiplexed halves to obtain a data rate of twice the clock frequency. The active area of the chip is 12 mm/SUP 2/ or 2900 /spl mu/m/SUP 2/ per bit. Operation was obtained for arbitrary data streams at clock rates of 1 kHz to 1.6 MHz (3.2 MHz data rate). Power dissipation varies linearly with frequency and is 16 /spl mu/W per bit at the highest frequency. Maximum read latency is 80 /spl mu/s at this frequency. This performance demonstrates the feasibility of the C4D as a component for a medium speed large-scale memory.