Advanced repeater utilizing signal distribution delay
View Patent ↗An advanced repeater utilizing signal distribution delay. In accordance with a first embodiment of the present invention, such an advanced repeater circuit comprises an output stage for driving an output signal line responsive to an input signal and a feedback loop coupled to said output signal line for changing state of said output stage subsequent to a delay after a transition of said output signal. The delay is due to transmission line effects of said output signal line.
1. A circuit comprising:
a drive circuit for selective driving an output node of the circuit high and low;
an OR gate having an output coupled to the drive circuit and a first input coupled to an input signal of the circuit;
an AND gate having an output coupled to the drive circuit and a first input coupled to the input signal; and
a non-inverting feedback loop coupled between the output node through an endpoint of a clock signal distribution network or tree to the second inputs of the OR gate and the AND gate, wherein the feedback loop includes a configuration to introduce a transmission line effect delay between the output node and the second inputs of the OR gate and the AND gate as a result of propagation from the output node to the endpoint of the clock signal distribution network or tree.
2. The circuit of claim 1 , wherein the drive circuit comprises a p-type transistor and an n-type transistor, wherein the gate of the p-type transistor is coupled to the output of the OR gate and the gate of the n-type transistor is coupled to the output of the AND gate.
3. The circuit of claim 1 , wherein the OR gate comprises a NOR gate and an inverter.
4. The circuit of claim 1 , wherein the AND gate comprises a NAND gate and an inverter.
5. The circuit of claim 1 , wherein the transmission line effect delay is sufficient for the drive circuit to drive the output node to a predetermined level.
6. The circuit of claim 1 , further comprising a keeper circuit coupled to the output node.
7. A repeater circuit comprising:
a driver circuit having an output coupled to an output node for driving the output node to a high and low state;
a feedback loop, coupled between the output node through an endpoint of a clock signal distribution network or tree to a first input of a control circuit, wherein the clock signal distribution network or tree includes a configuration to introduce a transmission line effect delay between the output node and the first input of the control circuit; and
the control circuit, having an output coupled to an input of the driver circuit and a second input coupled to an input node, and for causing the driver circuit to drive an output signal at the output node to a given one of the high or low state in response to a transition of an input signal at the input node and ceasing driving the output signal after the transmission line effect delay in response to a transition of the output signal.
8. The repeater circuit of claim 7 , wherein the driver circuit comprises:
a first transistor for driving the output node to the high state; and
a second transistor for driving the output node to the low state.
9. The repeater circuit of claim 8 , wherein the control circuit comprises:
an OR gate, for controlling the first transistor, having a first input coupled to an input node and a second input coupled to the feedback loop; and
an AND gate, for controlling the second transistor, having a first input coupled to the input node and a second input coupled to the feedback loop.
10. The repeater circuit of claim 7 , further comprising a keeper circuit coupled to the output node for weakly holding the output signal in its present state.
11. The repeater circuit of claim 7 , wherein the output signal is inverted relative to the input signal.
12. The repeater circuit of claim 7 , wherein the transmission line effect delay is long enough to drive the output signal to a given level and short enough not to resist a next transition of the output signal.
13. The repeater circuit of claim 7 , wherein the transmission line effect delay is short enough that the driver circuit stops driving the output signal prior to a next transition of the input signal.
14. A repeater circuit comprising:
a means for receiving an input signal; and
a means for driving an output signal to a given one of a high and a low state in response to a transition of the input signal and for ceasing driving the output signal after a delay in response to a transition of the output signal, wherein the delay is produced substantially by transmission line effects of propagation of the output signal to an endpoint of a clock signal distribution network coupled to the repeater circuit.
15. The repeater circuit of claim 14 , wherein the delay is long enough to drive the output signal to a given level on the transmission line and short enough not to resist a next transition of the output signal.