Nec Electronics Corporation

Koichiro Kiguchi

Takanori Saeki

Yasushi Aoki

Masashi Nakagawa

Tadashi Iwasaki

Masatomo Eimitsu

Minoru Nishizawa

Disclosed is a serial-to-parallel converter/parallel-to-serial converter/FIFO unified circuit which includes a register, a selector and a counter. The register receives serial input data and converts the serial data into parallel data based on frequency-divided multi-phase clock signals from a counter. The selector receives the parallel data from the register to select one of the data in accordance with a control signal. The counter generates the control signal for the selector so that plural items of data will be output serially from the selector in the sequence in which the plural items data have been serially supplied to the register.

Serial-to-parallel conversion/parallel-to-serial conversion/ FIFO unified circuit

Disclosed is a clock and data recover circuit including N flip-flops (F/Fs) for sampling an input data signal using N-phase clocks, a phase comparison circuit for performing phase comparison based on outputs of the F/Fs, a filter or smoothing a result of the phase comparison and outputting an up/down signal, up/down counters, each for receiving an output of the filter and counting up or down a count value thereof, a phase shift circuit for adjustably controlling phases of the clocks for edge detection and the clocks for data sampling according to phase control signals from an up/down counter and an up/down counter, respectively, and an up/down control circuit for receiving a control signal for controlling maximum and minimum values of count values of the up/down counter, generating a signal for controlling counting up and down of the up/down counter based on the count value of the up/down counter, and supplying the generated signal to the up/down counter.

Clock and data recovery circuit

Growing community of inventors

Kanagawa, Japan

Koichiro Kiguchi