Distributed front-end FIFO for source-synchronous interfaces with non-continuous clocks

1. An integrated circuit comprising:

one or more data I/O blocks, at least one data I/O block adapted to receive an incoming bit stream from an external device;

a clock I/O block adapted to receive an incoming clock signal from the external device;

one or more FIFOs, at least one FIFO connected to receive a corresponding incoming bit stream from a corresponding data I/O block; and

a FIFO controller adapted to control operations of the one or more FIFOs such that bits from the corresponding data I/O block are written into the at least one FIFO using a FIFO write clock that is based on the incoming clock signal.

2. The integrated circuit of claim 1 , wherein the incoming clock signal is asynchronous with a local reference clock signal of the integrated circuit.

3. The integrated circuit of claim 1 , wherein the incoming clock signal is a non-continuous strobe signal.

4. An integrated circuit comprising:

one or more data I/O blocks, at least one data I/O block adapted to receive an incoming bit stream from an external device;

one or more FIFOs, at least one FIFO connected to receive a corresponding incoming bit stream from a corresponding data I/O block; and

a FIFO controller adapted to control operations of the one or more FIFOs such that:

bits from the corresponding data I/O block are written into the at least one FIFO using a FIFO write clock that is based on an incoming clock signal; and

bits are read out from the at least one FIFO using a FIFO read clock that is based on a local reference clock signal.

5. The integrated circuit of claim 4 , wherein the incoming clock signal is asynchronous with the local reference clock signal.

6. The integrated circuit of claim 4 , wherein the FIFO controller comprises:

write-pointer circuitry adapted to generate, based on the FIFO write clock, write pointers for controlling the writing of bits into each FIFO; and

read-pointer circuitry adapted to generate, based on the FIFO read clock, read pointers for controlling the reading of bits from each FIFO.

7. An integrated circuit comprising:

a first-in, first-out structure (FIFO) adapted to receive an incoming bit stream from an external device; and

a FIFO controller adapted to control operation of the FIFO, such that:

bits from the incoming bitstream are written into the FIFO using a FIFO write clock that is based on an incoming clock signal from the external device; and

bits are read from the FIFO using a FIFO read clock that is based on a local reference clock signal of the integrated circuit that is asynchronous with the incoming clock signal.

8. The integrated circuit of claim 7 including a data I/O block adapted to receive the incoming bit stream from the external device, wherein the FIFO is connected to receive the incoming bit stream from the data I/O block.

9. The integrated circuit of claim 7 including a clock I/O block adapted to receive the incoming clock signal from the external device and to provide the FIFO write clock, wherein the FIFO controller is connected to the clock I/O block to receive the FIFO write clock.

10. The integrated circuit of claim 7 including a gearing block connected to the FIFO and adapted to convert a higher-speed data stream read from the FIFO into multiple lower-speed data streams for processing by the integrated circuit.

11. The integrated circuit of claim 7 , wherein the integrated circuit is a field programmable gate array (FPGA).

12. The integrated circuit of claim 7 , wherein the incoming clock signal is a non-continuous signal.

13. The integrated circuit of claim 7 , wherein the incoming clock signal and the local reference clock signal have the same frequency.