Reducing waiting time jitter

A method for reducing waiting time jitter in a synchronizer, the method comprising:

• generating a sub-bit phase comparison of read and write clocks used to pass unsynchronized data through an elastic store;
• comparing read and write pointers for the read and write clocks with a threshold level;
• generating a frame of synchronized data from the data in the elastic store with a length that is dependent on the result of comparing the read and write pointers with the threshold level;
• and
• selecting the threshold level used in comparing the read and write pointers based on the generated sub-bit phase comparison so as to reduce waiting time jitter.

A synchronizer circuit, comprising:

• an elastic store that receives an unsynchronized data stream;
• a write clock that controls the writing of data to the elastic store;
• a read clock that controls the reading of data from the elastic store;
• a multiplexer that receives the data read from the elastic store;
• a phase detector that compares the phase of the read and write clocks;
• a threshold generator that generates a variable threshold value based on an output of the phase detector;
• a comparator that compares an output of the phase detector with the threshold value;
• and
• a control logic coupled to the multiplexer that controls the insertion of stuff bits based on the output of the comparator so as to reduce waiting time jitter.

A synchronizer, comprising:

• an elastic store that receives an unsynchronized data stream;
• a multiplexer, coupled to the elastic store, that produces a synchronized data stream from the unsynchronized data stream by the controlled insertion of stuff bits;
• and
• a control circuit that controls the insertion of stuff bits into the synchronized data stream based on a comparison of the phase difference of clocks associated with the synchronized and unsynchronized data streams with a variable threshold level that is generated from a sub-bit phase comparison of clocks associated with the synchronized and unsynchronized data streams so as to reduce waiting time jitter.

A telecommunications network, comprising:

• a synchronizer;
• a desynchronizer;
• a synchronous link coupling the synchronizer to the desynchronizer;
• and
• wherein the synchronizer includes:
• an elastic store that receives an unsynchronized data stream;
• a multiplexer, coupled to the elastic store, that produces a synchronized data stream from the unsynchronized data stream by the controlled insertion of stuff bits;
• and
• a control circuit that controls the insertion of stuff bits into the synchronized data stream based on a comparison of the phase difference of clocks associated with the synchronized and unsynchronized data streams with a variable threshold level that is generated from a sub-bit phase comparison of clocks associated with the synchronized and unsynchronized data streams so as to reduce waiting time jitter.