# US 5,708,398 A · Dual voltage controlled oscillator using integrated transistor and negative differential resistance diode > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,708,398 A - Document ID: US5708398A - Status: Granted - Kind: A - Application number: 08/673,879 - Filed: 1996-07-01 - Granted: 1998-01-13 - Earliest claimed: 1996-07-01 - Assignees: Motorola, Inc. - Inventors: Jun Shen; Vijay K. Nair - Web page: https://patentgrep.com/patent/US5708398A ## CPC - H03B 7/14: active element being semiconductor device - H03B 7/08: being a tunnel diode - 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 dual voltage controlled oscillator including a transistor with a negative differential resistance diode coupled to a first terminal and an inductance coupled to a second terminal. Operating voltages are applied to the gate and drain of the transistor to set the oscillator to operating in a negative differential resistance region of the diode. The diode, the inductance and the operating voltages are connected so that varying either of the operating voltages varies the frequency of the oscillations at the output. ## Claims ### Claim 1 A dual voltage controlled oscillator comprising a three terminal transistor with a negative differential resistance diode coupled to a first terminal of the three terminal transistor and an inductance coupled to a second terminal of the three terminal transistor, two of the three terminals of the transistor having applied thereto operating voltages which set the oscillator to operating in a negative differential resistance region of the diode so that oscillations of a selected frequency are produced at an output terminal, and the transistor, the negative differential resistance diode, the inductance and the operating voltages being connected so that varying either of the operating voltages varies the frequency of the oscillations at the output. ### Claim 2 (depends on 1) A dual voltage controlled oscillator as claimed in claim 1 wherein the three terminal transistor and the negative differential resistance diode are integrated into a single heterojunction interband tunneling transistor. ### Claim 3 (depends on 1) A dual voltage controlled oscillator as claimed in claim 1 wherein the three terminals of the transistor are source, drain and gate terminals, and the negative differential resistance diode is connected to the source terminal of the transistor, the inductance is connected to the drain terminal, and the operating voltages are connected to the drain and gate terminals. ### Claim 4 (depends on 1) A dual voltage controlled oscillator as claimed in claim 1 wherein the three terminals of the transistor are source, drain and gate terminals, and the negative differential resistance diode is connected to the gate terminal of the transistor, the inductance is connected to the drain terminal, a second inductance is connected to the gate terminal and the operating voltages are connected to the drain and gate terminals through the inductances, respectively. ### Claim 5 A dual voltage controlled oscillator comprising a transistor having gate, drain and source terminals, a negative differential resistance diode coupled to the source terminal of the transistor, an inductance coupled to the drain terminal of the transistor, and operating voltages which set the oscillator to operating in a negative differential resistance region of the diode connected to the gate terminal and through the inductances to the drain terminal so that oscillations of a selected frequency are produced at an output terminal, and varying either of the operating voltages varies the frequency of the oscillations at the output. ### Claim 6 (depends on 5) A dual voltage controlled oscillator as claimed in claim 5 wherein the three terminal transistor and the negative differential resistance diode are integrated into a single heterojunction interband tunneling transistor. ### Claim 7 A dual voltage controlled oscillator comprising a transistor having gate, drain and source terminals, a negative differential resistance diode coupled to the gate terminal of the transistor, a first inductance coupled to the gate terminal of the transistor, a second inductance coupled to the drain terminal of the transistor, and operating voltages which set the oscillator to operating in a negative differential resistance region of the diode connected through the first and second inductances to the gate and drain terminals respectively so that oscillations of a selected frequency are produced at an output terminal, and varying either of the operating voltages varies the frequency of the oscillations at the output. ### Claim 8 (depends on 7) A dual voltage controlled oscillator as claimed in claim 7 wherein the three terminal transistor and the negative differential resistance diode are integrated into a single heterojunction interband tunneling transistor. ### Claim 9 A method of operating a dual voltage controlled oscillator comprising the steps of: providing a three terminal transistor with a negative differential resistance diode coupled to a first terminal of the three terminal transistor and an inductance coupled to a second terminal of the three terminal transistor; coupling operating voltages to the transistor which set the oscillator to operating in a negative differential resistance region of the diode so that oscillations of a selected frequency are produced at an output terminal; and varying either of the operating voltages to vary the frequency of the oscillations at the output. ### Claim 10 (depends on 9) A method of operating a dual voltage controlled oscillator as claimed in claim 9 wherein the step of providing the three terminal transistor with the negative differential resistance diode includes integrating the three terminal transistor and the negative differential resistance diode into a single heterojunction interband tunneling transistor. ### Claim 11 (depends on 9) A method of operating a dual voltage controlled oscillator as claimed in claim 9 wherein the step of providing the three terminal transistor includes providing gate, drain, and source terminals and the step of coupling operating voltages to the transistor includes coupling operating voltages to the gate and drain terminals. ### Claim 12 (depends on 11) A method of operating a dual voltage controlled oscillator as claimed in claim 11 wherein the step of varying either of the operating voltages includes varying both of the operating voltages. ### Claim 13 (depends on 9) A method of operating a dual voltage controlled oscillator as claimed in claim 9 wherein the step of providing a three terminal transistor with a negative differential resistance diode includes providing the transistor with source, drain and gate terminals, connecting the negative differential resistance diode to the source terminal of the transistor, connecting the inductance to the drain terminal, and coupling the operating voltages to the drain and gate terminals. ### Claim 14 (depends on 9) A method of operating a dual voltage controlled oscillator as claimed in claim 9 wherein the step of providing a three terminal transistor with a negative differential resistance diode includes providing the transistor with source, drain and gate terminals, connecting the negative differential resistance diode to the gate terminal of the transistor, connecting the inductance to the drain terminal, connecting a second inductance to the gate terminal, and coupling the operating voltages to the drain and gate terminals through the inductances, respectively.