Abstract: A method operates a first-in-first-out (FIFO) buffer with a first clock, and operates one of a read pointer or a write pointer of the FIFO buffer with the first clock while operating the other one of the read pointer or write pointer with a second clock. One of a serializer fed from the FIFO buffer output, or a de-serializer feeding the FIFO buffer input, is operated with the second clock. Timing pulses indicate that the pointer operating with the second clock has reached a predetermined point in its cycle. The phase of the second clock is adjusted based on a relationship between the timing pulses and an advance period of the pointer operating with the first clock. The pointer operating with the first clock is reset to achieve a desired value for the relationship. A skew created from adjusting the phase of the second clock is corrected.

Abstract: A method operates a first-in-first-out (FIFO) buffer with a first clock, and operates one of a read pointer or a write pointer of the FIFO buffer with the first clock while operating the other one of the read pointer or write pointer with a second clock. One of a serializer fed from the FIFO buffer output, or a de-serializer feeding the FIFO buffer input, is operated with the second clock. Timing pulses indicate that the pointer operating with the second clock has reached a predetermined point in its cycle. The phase of the second clock is adjusted based on a relationship between the timing pulses and an advance period of the pointer operating with the first clock. The pointer operating with the first clock is reset to achieve a desired value for the relationship. A skew created from adjusting the phase of the second clock is corrected.

Abstract: A data recovery circuit includes a comparator for providing a comparator output signal in response to a difference in voltage between a data input signal and the reference voltage, a sampling circuit for sampling the comparator output signal to provide a sample signal, a summing circuit for providing an up signal in response to an average of logic high values of the sample signal exceeding logic low values of the input samples signal, and a down signal in response to an average of the low logic values of the sample signal exceeding the logic high values of the sample signal, a counter for counting up in response to activations of the up signal and counting down in response to activations of the down signal to provide a count signal, and a reference voltage generator for generating the reference voltage in response to the count signal.

Abstract: A multi-link input/output (I/O) interface uses both feed-forward and feedback signaling to reduce the impact of noise on data capture at a memory controller. To transfer data from a source module to a destination module, a defined pattern is communicated from the memory module along a master channel concurrent with the memory module providing data via one or more slave channels. Based on the phase of the defined pattern as it is received, the multi-link I/O interface feeds forward to the slave channels control signaling whose phase reflects a predicted noise pattern for the system. Each slave channel performs CDR by adjusting timing of its corresponding capture clock signal based on the fed forward control signaling and based on feedback signaling for the corresponding slave channel, whereby the feedback signaling reflects an error measurement between a phase of a capture clock signal and transitions in received data.

Abstract: A multi-link input/output (I/O) interface uses both feed-forward and feedback signaling to reduce the impact of noise on data capture at a memory controller. To transfer data from a source module to a destination module, a defined pattern is communicated from the memory module along a master channel concurrent with the memory module providing data via one or more slave channels. Based on the phase of the defined pattern as it is received, the multi-link I/O interface feeds forward to the slave channels control signaling whose phase reflects a predicted noise pattern for the system. Each slave channel performs CDR by adjusting timing of its corresponding capture clock signal based on the fed forward control signaling and based on feedback signaling for the corresponding slave channel, whereby the feedback signaling reflects an error measurement between a phase of a capture clock signal and transitions in received data.