Method and transceiver system having a transmit clock signal phase that is phase-locked with a receive clock signal phase
View Patent ↗A transceiver system is disclosed that includes a plurality of transceiver chips. Each transceiver chip includes one or more SERDES cores. Each SERDES core includes one or more SERDES lanes. Each SERDES lane includes a receive channel and a transmit channel. The transmit channel of each SERDES lane is phase-locked with a corresponding receive channel. The transceiver system has the capability of phase-locking a transmit clock signal phase of a transmitting component with a receive clock signal phase of a receiving component that is a part of a different SERDES lane, a different SERDES core, a different substrate, or even a different board. Each SERDES core receives and transmits data to and from external components connected to the SERDES core, such as hard disk drives. A method of transferring data from a first external component coupled to a receive channel to a second external component coupled to a transmit channel is also disclosed.
1. A transceiver comprising:
a serializer/deserializer (SERDES) transmit channel including,
a receiver configured to receive receiver clock phase data from a SERDES receive channel;
a phase calculator configured to calculate a phase difference between a phase of a current receive clock signal and a phase of a previous receive clock signal based on the receiver clock phase data; and
a phase adjuster configured to adjust a phase of a current transmit clock signal, based on the calculated phase difference, so as to synchronize the phase of the current transmit clock signal with the phase of the current receive clock signal.
2. The transceiver of claim 1 , wherein the receiver is configured to receive a digitized bit sequence indicating the receiver clock phase data.
3. The transceiver of claim 1 , wherein
the phase calculator is further configured to calculate a direction associated with the phase difference, and
the phase adjuster is configured to adjust the phase of the current transmit clock signal based on the direction associated with the phase difference.
4. The transceiver of claim 1 , wherein the phase calculator comprises:
a delay register configured to provide the phase of the previous receive clock signal based on a previously stored receive clock signal.
5. The transceiver of claim 1 , wherein the phase calculator further comprises:
a multiplexer configured to receive the calculated phase difference and a predetermined phase difference, and to output a phase adjustment value based on a phase control signal.
6. The transceiver of claim 5 , wherein the receiver is configured to receive the predetermined phase difference from the SERDES receive channel.
7. The transceiver of claim 5 , wherein the phase adjuster is configured to receive the phase adjustment value and a phase of a previous transmit clock signal, and to adjust the phase of the current transmit clock signal based on the phase adjustment value.
8. The transceiver of claim 5 , wherein the phase calculator farther comprises:
a comparator configured to compare the phase adjustment value and a phase threshold value, and to determine whether the phase adjustment value exceeds the phase threshold value.
9. The transceiver of claim 8 , wherein the phase adjuster is configured to adjust the phase of the current transmit clock signal when the comparator determines that the phase adjustment value is less than the phase threshold value.
10. The transceiver of claim 1 , wherein the SERDES transmit channel further comprises:
an analog serializer to convert digital data received from the SERDES receive channel into analog data, and to transmit the analog data in accordance with the phase of the current transmit clock signal.
11. A method to be performed in a serializer/deserializer (SERDES) transceiver, the method comprising:
receiving, in the transceiver, receiver clock phase data from a SERDES receive channel;
calculating, in the transceiver, a phase difference between a phase of a current receive clock signal and a phase of a previous receive clock signal based on the receiver clock phase data; and
adjusting, in the transceiver, a phase of a current transmit clock signal, based on the calculated phase difference, to synchronize the phase of the current transmit clock signal with the phase of the current receive clock signal.
12. The method of claim 11 , wherein the receiving includes receiving a digitized bit sequence indicating the receiver clock phase data.
13. The method of claim 11 , further comprising
calculating a direction associated with the phase difference; and
adjusting the phase of the current transmit clock signal based on the direction associated with the phase difference.
14. The method of claim 11 , further comprising:
providing the phase of the previous receive clock signal based on a previously stored receive clock signal.
15. The method of claim 11 , further comprising:
receiving the calculated phase difference and a predetermined phase difference, and outputting a phase adjustment value based on a phase control signal.
16. The method of claim 15 , wherein the receiving the predetermined phase difference includes receiving the predetermined phase difference from the SERDES receive channel.
17. The method of claim 15 , wherein the adjusting includes receiving the phase adjustment value and a phase of a previous transmit clock signal, and adjusting the phase of the current transmit clock signal based on the phase adjustment value.
18. The method of claim 15 , further comprising:
receiving a phase threshold value; and
comparing the phase adjustment value and the phase threshold value to determine whether the phase adjustment value exceeds the phase threshold value.
19. The method of claim 18 , wherein the adjusting includes adjusting the phase of the current transmit clock signal when it is determined that the phase adjustment value is less than the phase threshold value in the comparing.
20. The method of claim 11 , further comprising:
converting digital data received from the SERDES receive channel into analog data, and transmitting the analog data in accordance with the phase of the current transmit clock signal.