# US 2013/0154750 A1 · Oscillator regeneration device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0154750 A1 - Document ID: US20130154750A1 - Status: Published application - Kind: A1 - Application number: 13/331,553 - Filed: 2011-12-20 - Published: 2013-06-20 - Earliest claimed: 2011-12-20 - Assignees: Analog Devices, Inc. - Inventors: Andrey Martchovsky - Web page: https://patentgrep.com/patent/US20130154750A1 ## CPC - H03B 5/1852: {the semiconductor device being a field-effect device} - H03B 2200/0016: including a ring, disk or loop shaped resonator - H03B: GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS (generators adapted for electrophonic musical instruments G10H; masers or lasers H01S; generation of oscillations in plasma H05H) ## Abstract A negative resistance device for a multiphase oscillator is disclosed. The negative resistance device is coupled to taps of the multiphase oscillator so that it injects no energy into the oscillator when the oscillator is most sensitive to noise, thereby decreasing the phase noise of the oscillator. The negative resistance device also guarantees the direction of movement of a traveling wave past the taps of the multiphase oscillator. ## Claims ### Claim 1 A multiphase oscillator comprising: one or an odd number of means for reversing a polarity of a wave traveling thereon; a pair of conductors arranged to form a closed loop when coupled with the polarity reversing means such that the wave traveling between the conductors imparts a first polarity between the conductors after a first traversal of the closed loop and a second polarity after a second traversal of the loop; and a plurality of regeneration devices, each said regeneration device connected between the pair of conductors of the closed loop at a particular position on the loop and having an output that matches the polarity between the conductors at the position of the regeneration device after a traveling wave has passed the position, each said regeneration device having an output that transitions as the traveling wave is passing the position of the device, said transition including a dwell time during which the device output neither sources nor sinks current. ### Claim 2 (depends on 1) The oscillator according to claim 1, wherein said regeneration devices have a characteristic switching time; and wherein each said regeneration device has a first input connected to one of the conductors at a first position and a second input connected to one of the conductors at a second position such that the time for a wave to travel between the first and second positions is approximately equal to the characteristic switching time of the regeneration device. ### Claim 3 (depends on 1) The oscillator according to claim 1, wherein each said regeneration device has a first input connected to one of the conductors at a first position, a second input connected to one of the conductors at a second position, and an output connected to one of the conductors at a third position, such that the time for a wave to travel between the first and third position is greater than the time for a wave to travel from the second position to the third position so that the wave is encouraged to travel in a direction from the first position to the third position. ### Claim 4 (depends on 1) The oscillator according to claim 1, wherein each said regeneration device includes a pair of n-channel transistors and a pair of p-channel transistors; and wherein each transistor has a gate, a source and, a drain, a channel being present between the source and the drain for conducting current when the gate exceeds a threshold voltage, wherein the channels of the p-channel transistors are connected in series and between a first supply voltage and the output, wherein the channels of the n-channel transistors are connected in series between a second supply voltage and the output, wherein the gates of the transistors whose drains are connected to the output are connected together and to a first position Phk on the closed loop, wherein the gates of the transistors whose sources are connected respectively to the supply voltages are connected together and to a second position Phj on the closed loop. ### Claim 5 (depends on 1) The oscillator according to claim 1, wherein each said regeneration device includes a pair of p-channel transistors at a first position on the loop and a pair of n-channel transistors at a second position on the loop adjacent to the first position; wherein each transistor has a gate, a source and, a drain, a channel being present between the source and the drain for conducting current when the gate exceeds a threshold voltage, wherein the channels of the p-channel transistors are connected in series between a first supply voltage and the output, wherein the channels of the n-channel transistors are connected in series between a second supply voltage and the output, wherein the gate of the p-channel transistor whose drain is connected to the output is connected to a position Phk on the closed loop, and wherein the gate of the p-channel transistor whose source is connected to the first supply is connected to a position Phj on the closed loop, wherein the gate of the n-channel transistor whose drain is connected to the output is connected to a position Phk on the closed loop, and wherein the gate of the p-channel transistor whose source is connected to the second supply is connected to a position Phj on the closed loop. ### Claim 6 A method for reducing phase noise in a multiphase oscillator, the method comprising: providing a plurality of negative resistance devices, each supplying energy to the oscillator to maintain oscillations of the oscillator; and switching the output of each negative resistance device in synchronism with the oscillations of the oscillator, such that, during the switching, the output has a time in which the negative resistance device neither sources current into nor sinks current from the oscillator, wherein the phase noise of the multiphase oscillator is reduced. ### Claim 7 (depends on 6) The method for reducing phase noise according to claim 6, wherein the multiphase oscillator is a rotary wave oscillator; and wherein the plurality of negative resistance devices promotes a particular direction of a traveling wave on the rotary wave oscillator. ### Claim 8 (depends on 6) The method for reducing phase noise according to claim 6, wherein crowbar current in the negative resistance devices is eliminated.