PAM-4 receiver using pattern-based clock and data recovery circuitry
AssigneeKorea University Research and Business Foundation
InventorsChulwoo Kim, Seung-Woo Park, Yoon-Jae Choi, Jin-Cheol Sim
Life of this patent
Estimating the term…
Abstract
Disclosed in a PAM-4 receiver using pattern-based clock and data recovery circuitry, which includes an analog front end that receives an external signal and recovers channel loss to output a refined PAM-4 signal, a comparison unit that receives the PAM-4 signal and compares the PAM-4 signal with a reference voltage to generate a recovery signal, and a recovery unit that receives the recovery signal and recovers data and a clock. The analog front end includes an equalizer that matches amplitudes of all frequency components of the external signal and an amplifier that amplifies an output signal of the equalizer.
Claims11
A pulse amplitude modulation-4 (PAM-4) receiver, comprising:
- an analog front end configured to receive an external signal and recover channel loss to output a refined PAM-4 signal;
- a comparison unit configured to receive the PAM-4 signal and compare the PAM-4 signal with a reference voltage to generate a recovery signal;
- and
- a recovery unit configured to receive the recovery signal and recover data and a clock,
- wherein the analog front end includes:
- an equalizer configured to match amplitudes of all frequency components of the external signal;
- and
- an amplifier configured to amplify an output signal of the equalizer, and
- wherein the comparison unit includes:
- a first phase comparator configured to compare the PAM-4 signal with the reference voltage, when the clock is 0 degree;
- a second phase comparator configured to compare the PAM-4 signal with the reference voltage, when the clock is 90 degrees;
- a third phase comparator configured to compare the PAM-4 signal with the reference voltage, when the clock is 180 degrees;
- and
- a fourth phase comparator configured to compare the PAM-4 signal with the reference voltage, when the clock is 270 degrees.
A pulse amplitude modulation-4 (PAM-4) receiver, comprising:
- an analog front end configured to receive an external signal and recover channel loss to output a refined PAM-4 signal;
- a comparison unit configured to receive the PAM-4 signal and compare the PAM-4 signal with a reference voltage to generate a recovery signal;
- and
- a recovery unit configured to receive the recovery signal and recover data and a clock,
- wherein the analog front end includes:
- an equalizer configured to match amplitudes of all frequency components of the external signal;
- and
- an amplifier configured to amplify an output signal of the equalizer,
- wherein the recovery unit includes:
- a data recovery unit configured to receive data recovery values from first to fourth phase comparators and recover the data;
- and
- a clock recovery unit configured to receive clock recovery values from the first to fourth phase comparators and recover the clock, and
- wherein the data recovery unit includes:
- a first data recoverer configured to receive a first recovery signal of the first phase comparator and recover the data;
- a second data recoverer configured to receive a second recovery signal of the second phase comparator and recover the data;
- a third data recoverer configured to receive a third recovery signal of the third phase comparator and recover the data;
- and
- a fourth data recoverer configured to receive a fourth recovery signal of the fourth phase comparator and recover the data, and
- wherein each of the first to fourth data recoverers recovers the data using a NAND gate.
A pulse amplitude modulation-4 (PAM-4) receiver, comprising:
- an analog front end configured to receive an external signal and recover channel loss to output a refined PAM-4 signal;
- a comparison unit configured to receive the PAM-4 signal and compare the PAM-4 signal with a reference voltage to generate a recovery signal;
- and
- a recovery unit configured to receive the recovery signal and recover data and a clock,
- wherein the analog front end includes:
- an equalizer configured to match amplitudes of all frequency components of the external signal;
- and
- an amplifier configured to amplify an output signal of the equalizer,
- wherein the recovery unit includes:
- a data recovery unit configured to receive data recovery values from first to fourth phase comparators and recover the data;
- and
- a clock recovery unit configured to receive clock recovery values from the first to fourth phase comparators and recover the clock, and
- wherein the clock recovery unit includes:
- a voting machine configured to generate a clock adjustment signal using No. 0 clock recovery value, No. 1 clock recovery value, a first value of the adjusted data, and a second value of the recovered data;
- and
- an oscillator configured to receive the clock adjustment signal and generate an adjusted clock.
Dependencies are inferred from the claim text.