Delay circuitry, clock generating circuitry, and phase synchronization circuitry

• US 6,259,293 B1
• Filed: 10/06/1999
• Issued: 07/10/2001
• Est. Priority Date: 06/15/1999
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Ishimi, Kouichi, Hayase, Kiyoshi
• Primary Examiner(s): Tran, Toan
• Assistant Examiner(s): COX, CASSANDRA F
• Application Number:
  US09/413,528
• Time in Patent Office: 643 Days
• Field of Search: 327/149, 327/161, 327/152, 327/156, 327/147, 327/158, 327/270, 327/277, 327/276
• US Class Current: 327/276
• CPC Class Codes: H03K 2005/00032 Dc control of switching transistors
• CPC Class Codes: H03K 5/133 using a chain of active delay devices
• CPC Class Codes: H03K 5/135 by the use of time reference signals, e.g. clock signals
• CPC Class Codes: H03L 7/07 using several loops, e.g. for redundant clock signal generation
• CPC Class Codes: H03L 7/0805 the loop being adapted to provide an additional control signal for use outside the loop
• CPC Class Codes: H03L 7/0812 and where no voltage or current controlled oscillator is used
• CPC Class Codes: H03L 7/0891 the up-down pulses controlling source and sink current generators, e.g. a charge pump
• CPC Class Codes: H03L 7/0995 the oscillator comprising a ring oscillator

Abstract

Delay circuitry includes a phase-locked loop or PLL for comparing the phase of a reference clock applied thereto with that of another clock to be compared to generate a control signal having a value corresponding to the phase difference between the phases of the reference clock and other clock, for generating the other clock using at least a plurality of delay elements connected into a loop, a time delay provided by each of the plurality of delay elements being controlled by the control signal, and for changing the value of the control signal so that the other clock is made to be in phase with the reference clock. The delay circuitry further includes a register for storing information to set a certain time delay, and a delay unit including a plurality of delay elements each of which provides an input with a time delay that is controlled by the control signal from the PLL, for determining the number of delay elements through which an input signal is to be passed according to the information stored in the register, so as to provide the input signal with the predetermined time delay.

Claims

1. Delay circuitry comprising:

phase locked loop means for comprising a phase of a reference clock applied thereto with that of another clock to be compared to generate a control signal having a value corresponding to a phase difference between the phases of the reference clock and the another clock, for generating the another clock using at least a plurality of first delay elements connected into a loop, a time delay provided by each of the plurality of first delay elements being controlled by the control signal, and for changing the value of the control signal so that the another clock is made to be in phase with the reference clock;

storage means for storing information to set a predetermined time delay; and

delay means, connected to said storage means, and including a plurality of second delay elements each of which provides an input with a time delay that is controlled by the control signal from said phase locked loop means, for determining the number of second delay elements through which an input signal is to be passed according to the information stored in said storage means, so as to provide the input signal with the predetermined time delay.

2. The delay circuitry according to claim 1, wherein said plurality of first delay elements included in said phase locked loop means are manufactured in the same semiconductor process that said plurality of second delay elements included in said delay means are manufactured.

3. The delay circuitry according to claim 1, wherein said delay circuitry further comprises a plurality of delay circuits connected in series, each of which includes said phase locked loop means, said storage means, and said delay means, and each of said plurality of delay circuits can change the predetermined delay time to be provided to an input applied thereto in steps of a different time step.

4. The delay circuitry according to claim 3, wherein in each of said plurality of delay circuits, said plurality of delay elements included in said oscillating means are manufactured in the same semiconductor process that said plurality of delay elements included in said delay means are manufactured.

5. Clock generating circuitry comprising:

at least a delay circuit including phase locked loop means for comprising a phase of a reference clock applied thereto with that of another clock to be compared to generate a control signal having a value corresponding to a phase difference between the phases of the reference clock and the another clock, for generating the another clock using at least a plurality of firs delay elements connected into a loop, a time delay provided by each of the plurality of first delay elements being controlled by the control signal, and for changing the value of the control signal so that the another clock is made to be in phase with the reference clock, storage means for storing information to set a predetermined time delay, and delay means connected to said storage means and including a plurality of second delay elements each of which provides an input with a time delay that is controlled by the control signal from said phase locked loop means, for determining the number of second delay elements through which an input signal is to be passed according to the information stored in said storage means, so as to provide the input signal with the predetermined time delay; and

clock generating means that forms a loop together with at least said delay circuit, for generating and furnishing a clock pulse having a certain basic pulse repetition period to said delay circuit, and for generating a clock having a predetermined pulse repetition period in cooperation with said delay circuit.

6. The clock generating circuitry according to claim 5, wherein said plurality of first delay elements included in said phase locked loop means are manufactured in the same semiconductor process that said plurality of second delay elements included in said delay means are manufactured.

7. The clock generating circuitry according to claim 5, wherein said clock generating circuitry further comprises a plurality of delay circuits connected in series, each of which includes the phase locked loop means for comparing the phase of the reference clock applied thereto with that of another clock to be compared to generate the control signal having the value corresponding to the phase difference between the phases of the reference clock and the another clock, for generating the another clock using at least the plurality of first delay elements connected into a loop, the time delay provided by each of the plurality of first delay elements being controlled by the control signal, and for changing the value of the control signal so that the another clock is made to be in phase with the reference clock, storage means for storing information to set the predetermine time delay, and the delay means including the plurality of second delay elements each of which provides the input with the time delay that is controlled by the control delay elements said phase locked loop means, for determine the number of second delay elements through which the input signal is to be passed according to the information stored in said storage means, so as to provide the input signal with the predetermined time delay, each of said plurality of delay circuits being able to change a certain time delay to be provided to an input applied thereto in steps of a different time step, and wherein said plurality of delay circuits form a loop together with said clock generating means.

8. The clock generating circuitry according to claim 7, wherein in each of said plurality of delay circuits, said plurality of first delay elements included in said phase locked loop means are manufactured in the same semiconductor process that said plurality of second delay elements included in said delay means are manufactured.

9. The clock generating circuitry according to claim 5, wherein said clock generating means is a means for inverting an output of said delay circuit that forms the loop together with said clock generating means so as to generate the clock having the predetermined pulse repetition period in cooperation with said delay circuit.

10. The clock generating circuitry according to claim 7, wherein said cock generating means is a means for inverting an output of one of said plurality of delay circuits in series that form the loop together with said clock generating means so as to generate the clock having the predetermined pulse repetition period in cooperation with said plurality of delay circuits.

11. The clock generating circuitry according to claim 5, wherein said clock generating circuitry further includes control means for comparing a phase of a reference clock applied thereto with that of another clock to be compared to generate a control signal having a value corresponding to a phase difference between the phases of the reference clock and the another clock, for generating the another clock using first delay means formed into a loop, a time delay provided by said first delay means being controlled by the control signal, and for changing the value of the control signal so that another clock is made to be in phase with the reference clock, and second delay means for inverting an output of said delay circuit that forms the loop together with said clock generating means and for providing the output with a time delay control by control signal from said control means so as to generate the clock having the predetermined pulse repetition period in cooperation with said delay circuit.

12. The clock generating circuitry according to claim 7, wherein said clock generating circuitry further includes control means for comparing a phase of a reference clock applied thereto with that of another clock to be compared to generate a control signal having a value corresponding to a phase difference between the phases of the reference clock and the another clock, for generating the another clock using first delay means formed into a loop, a time delay provide by said first delay means being controlled by the control signal, and for changing the value of the control signal so that the another clock is made to be in phase with the reference clock, and second delay means for inverting an output of one of said plurality of delay circuits in series that form the loop together with said clock generating means and for providing the output with a time delay controlled by the control signal from said control means so as to generate the clock having the predetermined pulse repetition period in cooperation with said plurality of delay circuits.

13. The clock generating circuitry according to claim 11, wherein said control means includes a plurality of third delay elements connected in series, which are disposed as said first delay means formed into a loop, a time delay provided by each of said plurality of third delay elements being controlled by the control signal, and wherein said second delay means of said clock generating means includes a plurality of fourth delay elements connected in series, a time delay provided by each of said plurality of fourth delay elements being controlled by the control signal from said control means.

14. The clock generating circuitry according to claim 13, wherein said plurality of third delay elements included in said control means are manufactured in the same semiconductor process that said plurality of fourth delay elements included in said second delay means of said clock generating means are manufactured.

15. The clock generating circuitry according to claim 11, wherein said control means includes a first digital delay line, which is disposed as said first delay means, a time delay provided by said first digital delay line being controlled by the control signal, and wherein said second delay means of said clock generating means includes a second digital delay line, a time delay provided by said second digital delay line being controlled by the control signal from said control means.

16. The clock generating circuitry according to claim 11, wherein the reference clock applied to at least said one of said first and second delay circuits has the same frequency as the reference clock applied to said clock generating means.

17. The clock generating circuitry according to claim 12, wherein the reference clock applied to at least one of said plurality of delay circuits has the same frequency as the reference clock applied to said clock generating means.

18. The clock generating circuitry according to claim 11, further comprising at least another delay circuit for adjusting the phase of the clock having the predetermined pulse repetition period from said clock generating means, said another delay circuit including the phase locked loop means for comprising the phase of the reference clock applied thereto with that of the another clock to be compared to generate the control signal having the value corresponding to the phase difference between the phases of the reference clock and the another clock, for generating the another clock using at least the plurality of first delay elements connected into the loop, the time delay provided by each of the plurality of first delay elements being controlled by the control signal, and for changing the value of the control signal so that the another clock is made to be in phase with the reference clock the storage means for storing information to set the predetermined time delay, and the delay means including the plurality of second delay elements each of which provides the input with the time delay that is controlled by the control signal from said phase locked loop means, for determining the number of second delay elements through which an input signal is to be passed according to the information stored in said storage means, so as to provide the clock from said clock generating means with the predetermined time delay.

19. Phase synchronization circuitry comprising:

phase locked loop means for comprising a phase of a first reference clock applied thereto with that of another clock to be compared to generate a control signal having a value corresponding to a phase difference between the phases of the first reference clock and the another clock, for generating the another clock using at least a plurality of first delay elements connected into a loop, a time delay provide by each of the plurality of first delay elements being controlled by the control signal, and for changing the value of the control signal so that the another clock is made to be in phase with the first reference clock;

storage means for storing information to set a predetermined time delay;

delay means including a plurality of second delay elements each of which provides an input with a time delay that is controlled by the control signal from said phase locked loop means, for changing the number of second delay elements through which an input clock signal is to be passed, so as to provide the input clock signal with the predetermined time delay; and

phase synchronization means, connected to said storage means, for comparing the phase of a second reference clock applied to thereto with that of an output clock signal from said delay means, and for changing the information stored in said storage means so that the second reference clock is made to be in phase with the output clock signal.

20. The delay circuitry according to claim 19, wherein said plurality of first delay elements included in said phase locked loop means are manufactured in the same semiconductor process that said plurality of second delay elements included in said delay means are manufactured.