Author: claimsbot

1. A multi-stage harvest dryer for drying an agricultural harvest product, the dryer comprising:
multiple drying stages connected in sequence to dry a volume of harvest product passed from one drying stage to the next; and
at least one heat exchanger located in at least one of the stages to transfer heat to the harvest product in the at least one of the stages.
2. The multi-stage harvest dryer of claim 1 wherein the at least one heat exchanger comprises a heat exchanger in the form of a radiant heat wall surface defining a drying chamber for one of the stages.
3. The multi-stage harvest dryer of claim 2 wherein the at least one heat exchanger further comprises another heat exchanger in the form of a condenser in one of the stages connected to receive water evaporated from the harvest product elsewhere in the dryer and located to transfer heat from the evaporated water to the harvest product.
4. The multi-stage harvest dryer of claim 3 wherein the condenser is located in the drying chamber.
5. The multi-stage harvest dryer of claim 3 wherein the at least one heat exchanger comprises another heat exchanger in the form of another radiant heat wall surface defining a drying chamber for another one of the stages.
6. The multi-stage harvest dryer of claim 5 wherein the at least one heat exchanger further comprises another heat exchanger in the form of another condenser in the another one of the stages connected to receive water evaporated from the harvest product elsewhere in the dryer and located to transfer heat from the evaporated water to the harvest product in the another one of the stages.
7. The multi-stage harvest dryer of claim 2 further comprising a hot water generating fuel cell connected to the radiant heat wall surface to supply water generated by the fuel cell to the radiant heat wall surface to transfer heat from the water to the radiant heat wall surface.
8. The multi-stage harvest dryer of claim 7 further comprising another fuel cell connected to the hot water cell to supply Hydrogen and Oxygen thereto.
9. The multi-stage harvest dryer of claim 2 wherein the radiant heat wall surface has a black surface finish facing the chamber.
10. The multi-stage harvest dryer of claim 1 further comprising a mechanical harvest product mover located in the at least one of the stages to circulate harvest product relative to the at least one heat exchanger.
11. A multi-stage harvest dryer for drying an agricultural harvest product, the dryer comprising:
a first radiant heat wall surface defining a first drying chamber for the harvest product;
a first heater located to transmit heat to the first radiant heat wall surface to maintain the wall surface within a desired temperature range;
a second radiant heat wall surface defining a second drying volume for the harvest product; and
a second heater located to transmit heat to the second radiant heat wall surface to maintain the second radiant heat wall surface within a desired temperature range, the second drying volume located downstream from the first drying volume to receive harvest product therefrom.
12. The multi-stage harvest dryer of claim 11 further comprising a condenser connected to receive water evaporated from the harvest product elsewhere in the dryer, the condenser located to transfer heat from the evaporated water to the harvest product in one of the drying chambers.
13. The multi-stage harvest dryer of claim 11 wherein each of the heaters is in the form of a water jacket surrounding the corresponding radiant heat wall surface to transfer heat from a hot water flow to the radiant heat wall surface.
14. The multi-stage harvest dryer of claim 13 further comprising at least one hot water generating fuel cell connected to the water jacket to supply the hot water flow thereto.
15. The multi-stage harvest dryer of claim 14 further comprising at least one other fuel cell connected to the at least one hot water generating fuel cell to supply hydrogen and oxygen thereto.
16. The multi-stage harvest dryer of claim 15 wherein the at least one other fuel cell is connected to the water jacket to received a cooled water flow therefrom to utilize in the generation of hydrogen and oxygen.
17. The multi-stage harvest dryer of claim 11 further comprising a mechanical harvest product mover located in each of the drying chambers to circulate harvest product relative to the radiant heat wall surfaces.
18. A multi-stage harvest dryer for drying an agricultural harvest product, the dryer comprising:
a first condenser in one of the stages connected to receive water evaporated from the harvest product in another of the stages and located to transfer heat from the evaporated water to the harvest product in the one of the stages; and
a second condenser in another one of the stages connected to receive water evaporated from the harvest product in another of the stages and located to transfer heat from the evaporated water to the harvest product in the another one of the stages.
19. The multi-stage harvest dryer of claim 18 wherein the first condenser is connected to the another one of the stages to receive water evaporated from the harvest product heated by the second condenser.
20. The multi-stage harvest dryer of claim 18 further comprising a header connected to the condensers to direct the evaporated water thereto.
21. The multi-stage harvest dryer of claim 18 further comprising:
a hot water generating fuel cell connected to at least one of the stages to supply water for heating the harvest product in the at least one of the stages; and
a second fuel cell connected to the hot water generating fuel cell to supply hydrogen and oxygen thereto, at least one of the condensers connected to the second fuel cell to supply condensed water thereto for the generation of hydrogen and oxygen.
22. The multi-stage harvest dryer of claim 18 further comprising:
a hot water generating fuel cell connected to at least one of the stages to supply water for heating the harvest product in the at least one of the stages; and
a second fuel cell connected to the hot water generating fuel cell to supply hydrogen and oxygen thereto, the at least one of the stages connected to the fuel cell to supply the water thereto for the generation of hydrogen and oxygen after the water has been cooled in the at least one of the stages.
23. A method of drying agricultural harvest product, the method comprising the steps of:
heating harvest product to evaporate water therefrom;
collecting the evaporated water; and
condensing the evaporated water by transferring heat therefrom to harvest product that has not yet undergone the heating step.
24. The method of claim 23 wherein the heating step comprises radiant heat transfer to the harvest product.
25. The method of claim 24 wherein the heating step comprises generating hot water from a fuel cell and heating a radiant heat surface with the hot water.
26. The method of claim 25 further comprising the step of supplying water from the condensing step to a fuel cell to generate hydrogen and oxygen therefrom.
27. The method of claim 25 further comprising the step of supplying water from the heating step to a fuel cell to generate hydrogen and oxygen therefrom.
28. The method of claim 23 wherein the heating step comprises condensing water evaporated from the harvest product during another step of the method.
29. The method of claim 23 wherein the heating and condensing steps occur at the same time.
30. A method of drying agricultural harvest product, the method comprising the steps of:
heating harvest product via radiant heat transfer from a surface surrounding the harvest product in a first stage;
transferring the harvest product to a second stage; and
heating harvest product via radiant heat transfer from a surface surrounding the harvest product in the second stage.
31. The method of claim 30 further comprising the steps of:
collecting water evaporated from the harvest product in the second stage; and
condensing the evaporated water by transferring heat therefrom to harvest product in the first stage.
32. The method of claim 30 wherein each of the heating steps comprises generating hot water-from a fuel cell and heating a radiant heat surface with the hot water.
33. The method of claim 32 further comprising the step of supplying water from the heating step to a fuel cell to generate hydrogen and oxygen therefrom.
34. The method of claim 30 wherein harvest product is heated in the first stage while harvest product is being heated in the second stage.
35. The method of claim 30 wherein each of the heating steps comprises circulating the harvest product relative to the surface.

The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.

1. A method for controlling a cooling water tower comprising:
a. providing a cooling tower system, which includes a recirculated evaporative cooling water stream defined by an evaporative cooling water volume, a source of make-up water, an evaporative cooling unit, a heat exchanger, a bleed off line, and a bleed-off valve which is in communication with said bleed-off line;
b. providing a plurality of conduits through which said makeup water flows into said evaporative cooling water stream, wherein there is at least a first conduit that contains a weak acid cation ion exchange column and a second conduit that does not contain a weak acid ion exchange column, and wherein each conduit has at least one conduit valve;
c. choosing a pH setpoint value, a conductivity setpoint value and a deadband value above and below said pH setpoint value, a deadband value above and below said conductivity setpoint value, in said cooling tower system;
d. defining conductivity values C1-C3 and pH values P1-P3, wherein
C1 is the conductivity value when conductivity is greater than sum of the setpoint value and deadband value,
C2 is the conductivity value when conductivity is less than the sum of the setpoint value and deadband value and higher than the setpoint value less the deadband value,
C3 is the conductivity value when conductivity is less than the setpoint value lowered by the deadband value,
P1 is the pH value when the pH is greater than sum of the setpoint value and deadband value,
P2 is the pH value when pH is less than the sum of the setpoint value and deadband value and higher than the setpoint value less the deadband value,
P3 is the pH value when pH is less than the setpoint value lowered by the deadband value;
e. measuring both the pH of said evaporative cooling water stream with one or more pH meters and conductivity of said evaporative cooling water stream with one or more conductivity meters;
f. implementing the following response to said conductivity measurements and pH measurements:
(i) if the conductivity is C1 and the pH is PI, then said bleed-offvalve is on and water is blowdown from said cooling tower until said evaporative cooling water volume reaches a first predetermined level, and makeup water is added to said evaporative cooling water stream through said first conduit until said evaporative cooling water volume reaches a second predetermined level; or
(ii) if the conductivity is C1 and the pH is P2, then said bleed-offvalve is on and water is blowdown from said cooling tower until said evaporative cooling water volume reaches a first predetermined level, and makeup water is added to said evaporative cooling water stream through said second conduit until said evaporative cooling water volume reaches a second predetermined level; or
(iii) if the conductivity is C1 and the pH is P3, then said bleed-offvalve is on and water is blowdown from said cooling tower until said evaporative cooling water volume reaches a first predetermined level, and makeup water is added to said evaporative cooling water stream through said second conduit until said evaporative cooling water volume reaches a second predetermined level; or
(iv) if the conductivity is C2 and the pH is P1, then the bleed-off valve is on when the conductivity is falling from C1 and water is blowdown from said cooling tower until said evaporative cooling water volume reaches a first predetermined level, and makeup water is added to said evaporative cooling water stream through said first conduit until said evaporative cooling water volume reaches a second predetermined level; or
(v) if the conductivity is C2 and the pH is P2, then the bleed-offvalve is on when the conductivity is falling from CI and water is blowdown from said cooling tower until said evaporative cooling water volume reaches a first predetermined level, and makeup water is added to said evaporative cooling water stream through said second conduit until said evaporative cooling water volume reaches a second predetermined level; or
(vi) if the conductivity is C2 and the pH is P3, then the bleed-offvalve is on when the conductivity is falling from C1 and water is blowdown from said cooling tower until said evaporative cooling water volume reaches a first predetermined level, and makeup water is added to said evaporative cooling water stream through said second conduit until said evaporative cooling water volume reaches a second predetermined level; or
(vii) if the conductivity is C3 and the pH is P1, then said bleed-off valve is on and water is blowdown from said cooling tower until said evaporative cooling water volume reaches a first predetermined level, and makeup water is added to said evaporative cooling water stream through said first conduit until said evaporative cooling water volume reaches a second predetermined level;
(viii) if the conductivity is C3 and the pH is P2, then the bleed-offvalve is off; or
(ix) if the conductivity is C3 and the pH is P3, then the bleed-offvalve is off.
2. The method of claim 1 further comprising one or more controllers which are in communication with said pH meters and said conductivity meters, wherein said controllers are programmed to implement said response to said pH measurements and said conductivity measurements.
3. The method of claim 2 wherein said controllers are web-based.
4. The method of claim 2 wherein said at least one conduit valve in the first conduit includes said first conduit having a first valve attached to it and said at least one conduit valve in the second conduit includes said second conduit having a second valve attached to it.
5. The method of claim 4 wherein said first valve andor said second valve has a solenoid that receives input from said controllers and implements a response in accord with said programmed controllers.
6. The method of claim 1 wherein said weak acid cation exchange column absorbs Ca++ and Mg++ cations.
7. The method of claim 1 wherein said first predetermined level and said second predetermined level are controlled by a float valve.

1. A cluster resonator, comprising:
a first conducting plane;
a second substantially parallel conducting plane;
a cluster of vias of essentially uniform length oriented substantially normal to the conducting planes each via in the cluster comprising a first end and a second end;
a first conducting pad disposed in a third plane substantially parallel and capacitively coupled to the first conducting plane and physically coupled with the vias of the cluster of vias proximate their first ends; and
a second conducting pad disposed in a fourth plane substantially parallel and capacitively coupled to the second conducting plane and physically coupled with the vias of the cluster of vias proximate their second ends, wherein the vias are physically connected to only the first and second conducting pads; and
wherein a combined inductance and capacitance of the cluster of vias form an electromagnetically resonant shunt circuit between the first and second conducting planes; and
wherein the vias of the cluster of vias are disposed along a perimeter that defines an interior region and one or more interior vias are routed within the interior region of the cluster of vias; and
wherein the interior vias comprise portions of transmission lines passing electrical signals through the cluster resonator.
2. A cluster resonator, comprising:
a first conducting plane;
a second substantially parallel conducting plane;
a cluster of vias of essentially uniform length oriented substantially normal to the conducting planes, each via in the cluster comprising a first end and a second end;
a first conducting pad disposed in a third plane substantially parallel and capacitively coupled to the first conducting plane and physically coupled with the vias of the cluster of vias proximate their first ends; and
a second conducting pad disposed in a fourth plane substantially parallel and capacitively coupled to the second conducting plane and physically coupled with the vias of the cluster of vias proximate their second ends, wherein the vias are physically connected to only the first and second conducting pads; and
wherein the first or second conducting pad is external relative to the first and second conducting planes.
3. The cluster resonator of claim 1, wherein the first or second conducting pad is internal relative to the first and second conducting planes.
4. The cluster resonator of claim 1, wherein the first and second conducting pads are internal relative to the first and second conducting planes.
5. The cluster resonator of claim 1, wherein the first and second conducting pads are external relative to the first and second conducting planes.
6. The cluster resonator of claim 1 or 2, wherein its topology comprises a mechanically balanced structure.
7. The cluster resonator of claim 1 or 2, wherein the first and second conducting planes are metallic layers incorporated with a multi-layered panel circuit.
8. The cluster resonator of claim 7, wherein the multi-layered panel circuit is a multi-layered printed circuit board and the cluster resonator comprises an array of plated through holes.
9. The cluster resonator of claim 7, wherein the multi-layered panel circuit is a multi-chip module.
10. The cluster resonator of claim 7, wherein the multi-layered panel circuit is a semiconductor chip.
11. The cluster resonator of claim 1, wherein the cluster of vias is disposed along a circular path.
12. The cluster resonator of claim 1, wherein the cluster of vias is disposed along an elliptical path.
13. The cluster resonator of claim 1, wherein the cluster of vias is disposed along a polygonal path.
14. The cluster resonator of claim 1, wherein spacing of vias within the cluster of vias effects a Faraday cage that substantially shields the interior region from RF fields propagating within the first and second conducting planes.
15. The cluster resonator of claim 14, wherein spacing of the vias within the cluster of vias in relation to the interior vias effects a predetermined line impedance in the interior vias.
16. A cluster resonator, comprising:
a first conducting plane;
a second substantially parallel conducting plane;
a cluster of vias of essentially uniform length oriented substantially normal to the conducting planes, each via in the cluster comprising a first end and a second end;
first ends of each via in the cluster of vias coupled with the first conducting plane; and
a first conducting pad disposed in a third plane parallel and external to the region between the first and second conducting planes and capacitively coupled to the second conducting plane and physically coupled to each via in the cluster of vias proximate their second ends, wherein the vias in the cluster of vias are physically connected to only the first conducting plane and the first conducting pad.
17. The cluster resonator of claim 16, wherein a combined inductance and capacitance of the cluster of vias form an electromagnetically resonant shunt circuit between the first and second conducting planes.
18. The cluster resonator of claim 16, wherein the vias of the cluster of vias are disposed along a perimeter that defines an interior region.
19. The cluster resonator of claim 18, wherein one or more interior vias are routed within the internal region of the cluster of vias.
20. The cluster resonator of claim 19, wherein the interior vias comprise portions of transmission lines passing electrical signals through the resonant element.
21. The cluster resonator of claim 16 comprising a second cluster of vias, each via in the second cluster of vias comprising a first end and a second end, wherein the vias in the second cluster of vias are coupled proximate their first ends to the second conducting plane and proximate their second ends to a second conducting pad disposed in a fourth plane parallel and external to the region between the first and second conducting planes and capacitively coupled to the first conducting plane, wherein the vias in the cluster of vias are physically connected to only the second conducting plane and the second conducting pad.
22. The cluster resonator of claim 21 wherein its topology comprises a mechanically balanced structure.
23. The cluster resonator of claim 16, wherein the first and second conducting planes are metallic layers incorporated with a multi-layered panel circuit.
24. The cluster resonator of claim 23, wherein the multi-layered panel circuit is a multi-layered printed circuit board and the cluster resonator comprises an array of plated through holes.
25. The cluster resonator of claim 16, wherein the multi-layered panel circuit is a multi-chip module.
26. The cluster resonator of claim 16, wherein the multi-layered panel circuit is a semiconductor chip.
27. The cluster resonator of claim 18, wherein the cluster of vias is disposed along a circular path.
28. The cluster resonator of claim 18, wherein the cluster of vias is disposed along an elliptical path.
29. The cluster resonator of claim 18 wherein the cluster of vias is disposed along a polygonal path.
30. The cluster resonator of claim 19, wherein spacing of the vias of the cluster of vias effects a Faraday cage that substantially shields the interior region from RF fields propagating within the first and second conducting planes.
31. The cluster resonator of claim 30, wherein spacing of the vias of the cluster of vias in relation to the interior vias effects a predetermined line impedance in the interior vias.
32. The cluster resonator of claims 1 or 6, further comprising a plurality of resonant vias and associated first and second conducting pads disposed in a periodic array associated with the first and second conducting planes.
33. The cluster resonator of claim 16, further comprising a plurality of resonant vias and associated first conducting pads disposed in a periodic array associated with the first and second conducting planes.
34. The cluster resonator of claims 1 or 6, wherein a diameter of the vias of the cluster of vias is selected to effect a predetermined inductance.
35. The cluster resonator of claim 16, wherein a diameter of the vias of the cluster of vias is selected to effect a predetermined inductance.
36. A cluster resonator comprising:
a first conducting plane;
a second substantially parallel conducting plane;
a first conducting pad disposed in a third substantially parallel plane internal to the region between the first and second conducting planes;
a first cluster of vias oriented substantially normal to the first conducting plane and first conducting pad and disposed therebetween, each via of the cluster having a first end and a second end, wherein the first and second ends are physically connected respectively to the first conducting plane and first conducting pad; and
a second conducting pad disposed in a fourth substantially parallel plane internal to the region between the first and second conducting planes;
a second cluster of vias oriented substantially normal to the second conducting plane and second conducting pad and disposed therebetween, each via of the cluster having a first end and a second end, wherein the first and second ends are physically connected respectively to the second conducting plane and second conducting pad; and
wherein the first and second conducting pads are proximate and capacitively coupled to each other; and
wherein the vias of the clusters of vias are disposed along a common perimeter thereby forming substantially field free interior regions therewithin; and
wherein one or more electrically isolated interior vias traverse the interior regions of the clusters of vias, the interior vias comprising portions of transmission lines for passing electrical signals therethrough.
37. The cluster resonator of claim 36, wherein a spacing of the vias of the clusters of vias in relation to the interior vias is selected to effect a predetermined line impedance in the interior vias.
38. The cluster resonator of claim 36, wherein a diameter of the vias of the clusters of vias is selected to effect a predetermined inductance.
39. The cluster resonator of claim 36, wherein the common perimeter is circular.
40. The cluster resonator of claim 36, wherein the common perimeter is elliptical.
41. The cluster resonator of claim 36, wherein the common perimeter is polygonal.
42. The cluster resonator of claim 36, wherein the first and second conducting planes are metallic layers incorporated within a multi-layered panel circuit.
43. The cluster resonator of claim 42, wherein the multi-layered panel circuit is a multi-layered printed circuit board and the cluster resonator comprises an array of plated through holes.
44. The cluster resonator of claim 42, wherein the multi-layered panel circuit is a multi-chip module.
45. The cluster resonator of claim 42, wherein the multi-layered panel circuit is a semiconductor chip.

The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.

1. A variable delay circuit comprising:
a delay circuit that includes a first delay unit and a second delay unit and delays an input signal to generate an output signal;
a selection signal generation unit that detects a delay value of the delay circuit and generates a selection signal to select a delay unit for delaying the input signal from the first delay unit and the second delay unit;
a first control unit that controls a delay value of the delay unit selected by the selection signal in response to a delay increasedecrease signal; and
a second control unit that controls a delay value of the delay unit which is not selected by the selection signal.
2. The variable delay circuit of claim 1, wherein the input signal is a clock, and the second control unit controls the delay value of the non-selected delay unit to be N*clock (N is an integer of 2 or larger)\u2212the delay value of the selected delay unit.
3. The variable delay circuit of claim 2, wherein the selection signal generation unit generates a selection signal to change a delay unit selected at a time when a difference between the delay values of the first delay unit and the second delay unit becomes M*clock (M is an integer of 1 or larger).
4. The variable delay circuit of claim 1, wherein the first control unit includes a first charge pump that generates a first chargingdischarging current in response to the delay increasedecrease signal.
5. The variable delay circuit of claim 4, wherein the second control unit includes:
a total delay detector that receives the input signal and a signal obtained from the input signal passing through the first delay unit and the second delay unit and generates a control signal for controlling the delay value of the delay unit which is not selected by the selection signal; and
a second charge pump that generates a second chargingdischarging current in response to the control signal.
6. The variable delay circuit of claim 5, wherein the first delay unit includes:
a first selection unit configured to select one of the first chargingdischarging current and the second chargingdischarging current;
a first loop filter configured to be charged and discharged in response to an output of the first selection unit; and
a first voltage controlled delay line configured to delay an input signal to make an output in response to a voltage charged in the first loop filter.
7. The variable delay circuit of claim 6, wherein the second delay unit includes:
a second selection unit configured to select one of the first chargingdischarging current and the second chargingdischarging current;
a second loop filter configured to be charged and discharged in response to an output of the second selection unit; and
a second voltage controlled delay line configured to delay an input signal to make an output in response to an output voltage of the second loop filter.
8. The variable delay circuit of claim 5, wherein the delay circuit includes:
a third selection unit configured to input one of the input signal and the output signal of the second delay unit to the first delay unit in response to the selection signal;
a fourth selection unit configured to input one of the output signal of the first delay unit and the input signal to the second delay unit in response to the selection signal; and
a fifth selection unit configured to select one of the output signals of the first delay unit and the second delay unit as an output signal of the variable delay circuit in response to the selection signal and transmit the other signal to the second control unit.
9. A delay-locked loop comprising:
a variable delay unit that delays an external clock to output an internal clock;
a replica delay unit that delays the internal clock to generate a feedback clock; and
a phase comparison unit that compares a phase of the feedback clock with a phase of the external clock to generate a delay increasedecrease signal,
wherein the variable delay unit includes:
a delay circuit that includes a first delay unit and a second delay unit and delays the external signal to generate the internal signal;
a selection signal generation unit that detects a delay value of the delay circuit and generates a selection signal to select a delay unit for delaying the external signal from the first delay unit and the second delay unit;
a first control unit that controls a delay value of the delay unit selected by the selection signal in response to a delay increasedecrease signal; and
a second control unit that controls a delay value of the delay unit which is not selected by the selection signal.
10. The delay-locked loop of claim 9, wherein the second control unit controls the delay value of the non-selected delay unit to be N*clock (N is an integer of 2 or larger)\u2212the delay value of the selected delay unit.
11. The delay-locked loop of claim 10, wherein the selection signal generation unit generates a selection signal to change a delay unit selected at a time when a difference between the delay values of the first delay unit and the second delay unit becomes M*clock (M is an integer of 1 or larger).
12. The delay-locked loop of claim 11, wherein the first control unit includes:
a first charge pump that generates a first chargingdischarging current in response to the delay increasedecrease signal, and
the second control unit includes:
a total delay detector that receives the input signal and a signal obtained from the input signal passing through the first delay unit and the second delay unit and generates a control signal for controlling the delay value of the delay unit which is not selected by the selection signal; and
a second charge pump that generates a second chargingdischarging current in response to the control signal.
13. The delay-locked loop of claim 12, wherein the first delay unit includes:
a first selection unit configured to select one of the first chargingdischarging current and the second chargingdischarging current;
a first loop filter configured to be charged and discharged in response to an output of the first selection unit; and
a first voltage controlled delay line configured to delay an input signal to make an output in response to a voltage charged in the first loop filter, and
the second delay unit includes:
a second selection unit configured to select one of the first chargingdischarging current and the second chargingdischarging current;
a second loop filter configured to be charged and discharged in response to an output of the second selection unit; and
a second voltage controlled delay line configured to delay an input signal to make an output in response to an output voltage of the second loop filter.
14. The delay-locked loop of claim 12, wherein the delay circuit includes:
a third selection unit configured to input one of the input signal and the output signal of the second delay unit to the first delay unit in response to the selection signal;
a fourth selection unit configured to input one of the output signal of the first delay unit and the input signal to the second delay unit in response to the selection signal; and
a fifth selection unit configured to select one of the output signals of the first delay unit and the second delay unit as an output signal of the variable delay circuit in response to the selection signal and transmit the other signal to the second control unit.