摘要:
A phase locked loop having reduced inherent noise is provided. The phase locked loop comprises a controlled oscillator for outputting a periodic output signal as a result of a control signal; a feedback unit for providing at least two periodic feedback signals having a constant phase shift to each other and each depending on the output signal; a phase/frequency detector for providing difference signals each depending on a periodic input signal and at least one of the feedback signals; and a control circuit for providing the control signal to the controlled oscillator depending on the difference signals.
摘要:
The invention provides a data handover unit for transferring data from a furst clock domain to a second clock domain, comprising: a first clock unit operable to supply a first clock signal; a selector stage operable to sample an incoming data stream with respect to the first clock signal; a second clock unit operable to supply a second clock signal; a storage unit coupled with the selector stage, wherein the storage unit has a first plurality of storage elements each of which is operable to store one bit of data of the sampled data stream, an output unit for parallelly reading out a fram of data from a second plurality of storage elements included in the first plurality of storage elements with respect to the second clock signal, wherein the selector stage is further operable to successively write the data bits of the sampled data stream into the first plurality of storage elements and to store the respective data bits of the sampled data stream in the respective storage elements until they were read out by the output unit.
摘要:
A data receiver has a sampling unit connected to a data signal input and configured to sample a data signal amplitude and amplify the sampled data signal amplitude to a predetermined value, a sampling clock generator unit connected to the sampling unit and configured to predetermine a sampling clock for the sampling unit, an evaluation unit connected to the sampling unit and configured to determine the time duration required by the sampling unit for amplifying the sampled data signal amplitude to the predetermined value and evaluate the time duration determined, and a control unit connected to the evaluation unit and the sampling clock generator and configured to define the sampling clock on the basis of the evaluation of the time duration determined by the evaluation unit.
摘要:
A method of transmitting data between different clock domains includes receiving data bits on the basis of a receiving clock, sequentially storing the data bits in a ring buffer, simultaneously transmitting a number of the stored data bits from the ring buffer on the basis of a first transmitting clock, and transmitting the stored data bits from the ring buffer on the basis of a second transmitting clock.
摘要:
A high-speed interface circuit is implemented in a semiconductor memory chip including a memory core, a first interface circuit section, and a second interface circuit section. The first interface circuit section is connectable to a write data-/command and address signal bus, includes a write data-/command and address re-driver/transmitter path (which may be transparent) and does not include any clock signal synchronizing circuitry, and a main write signal path including a serial-to-parallel converting and synchronizing device to synchronize with a reference clock signal received write data-/command and address signals and delivering the parallel converted write signals to the memory core. The second interface circuit section is connectable to a read data bus and includes a transparent read data re-driver/transmitter path for transmitting and re-driving received serial read data to a succeeding semiconductor memory chip and a main read signal path for inserting the parallel-to-serial converted read data from the memory core into the received serial read data stream, synchronizing the parallel-to-serial converted read data with the reference clock signal and providing the serialized read data stream to a serial read data input terminal of a corresponding second interface circuit section of a succeeding same memory chip or to a memory controller.
摘要:
A data receiver has a sampling unit connected to a data signal input and configured to sample a data signal amplitude and amplify the sampled data signal amplitude to a predetermined value, a sampling clock generator unit connected to the sampling unit and configured to predetermine a sampling clock for the sampling unit, an evaluation unit connected to the sampling unit and configured to determine the time duration required by the sampling unit for amplifying the sampled data signal amplitude to the predetermined value and evaluate the time duration determined, and a control unit connected to the evaluation unit and the sampling clock generator and configured to define the sampling clock on the basis of the evaluation of the time duration determined by the evaluation unit.
摘要:
The invention provides a data handover unit for transferring data from a first clock domain to a second clock domain, comprising: a first clock unit operable to supply a first clock signal; a selector stage operable to sample an incoming data stream with respect to the first clock signal; a second clock unit operable to supply a second clock signal; a storage unit coupled with the selector stage, wherein the storage unit has a first plurality of storage elements each of which is operable to store one bit of data of the sampled data stream, an output unit for parallelly reading out a frame of data from a second plurality of storage elements included in the first plurality of storage elements with respect to the second clock signal, wherein the selector stage is further operable to successively write the data bits of the sampled data stream into the first plurality of storage elements and to store the respective data bits of the sampled data stream in the respective storage elements until they were read out by the output unit.
摘要:
A digital control loop and a method for clock generation. A control loop includes at least one phase detector configured to detect a phase shift of a feedback signal relative to a reference clock signal and output a correction signal on the basis of the phase shift detected. At least one control loop filter is configured to output, on the basis of the correction signal, a first control signal and a second control signal, the first control signal being substantially the same as the second control signal except that oscillations are suppressed in the second control signal. At least one first phase generator is configured to output a first clock signal on the basis of the first control signal and the first phase reference signal, wherein the first clock signal is transmitted at least partially as feedback signal to the phase detector. At least one second phase generator receives the second control signal and the first phase reference signal, wherein the second phase generator is functionally substantially the same as the first phase generator and is configured to output a second clock signal on the basis of the second control signal and the first phase reference signal.
摘要:
A phase locked loop having reduced inherent noise is provided. The phase locked loop comprises a controlled oscillator for outputting a periodic output signal as a result of a control signal; a feedback unit for providing at least two periodic feedback signals having a constant phase shift to each other and each depending on the output signal; a phase/frequency detector for providing difference signals each depending on a periodic input signal and at least one of the feedback signals; and a control circuit for providing the control signal to the controlled oscillator depending on the difference signals.
摘要:
A digital control loop and a method for clock generation. A control loop includes at least one phase detector configured to detect a phase shift of a feedback signal relative to a reference clock signal and output a correction signal on the basis of the phase shift detected. At least one control loop filter is configured to output, on the basis of the correction signal, a first control signal and a second control signal, the first control signal being substantially the same as the second control signal except that oscillations are suppressed in the second control signal. At least one first phase generator is configured to output a first clock signal on the basis of the first control signal and the first phase reference signal, wherein the first clock signal is transmitted at least partially as feedback signal to the phase detector. At least one second phase generator receives the second control signal and the first phase reference signal, wherein the second phase generator is functionally substantially the same as the first phase generator and is configured to output a second clock signal on the basis of the second control signal and the first phase reference signal.