# US 9,438,167 B2 · Oscillation circuit, oscillator, manufacturing method of oscillator, electronic device, and moving object > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,438,167 B2 - Document ID: US9438167B2 - Status: Granted - Kind: B2 - Application number: 14/527,052 - Filed: 2014-10-29 - Published: 2015-04-30 - Granted: 2016-09-06 - Earliest claimed: 2013-10-30 - Assignees: Seiko Epson Corporation - Applicants: Seiko Epson Corporation - Inventors: Yosuke Itasaka; Masayuki Ishikawa; Takehiro Yamamoto; Akihiro Fukuzawa - Web page: https://patentgrep.com/patent/US9438167B2 ## CPC - H03B 5/366: {and comprising means for varying the frequency by a variable voltage or current} - H03B 5/362: {the amplifier being a single transistor (H03B5/364 - H03B5/368 take precedence)} - H03L 1/00: Stabilisation of generator output against variations of physical values, e.g. power supply - Y10T 29/49007: Indicating transducer - 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) - H03L: AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES (generation of oscillations H03B) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract An oscillation circuit includes: an oscillation unit which includes a first terminal and a second terminal connected to a resonator, a third terminal, a fourth terminal to which at least one of a power supply potential and a signal for inspecting the resonator is applied, a first switching unit which switches modes of electrical connection between the first terminal and the third terminal, and a second switching unit which switches modes of electrical connection between the second terminal and the fourth terminal. ## Claims ### Claim 1 An oscillation circuit comprising: an oscillation unit that includes a first terminal and a second terminal connected to a resonator; a third terminal; a fourth terminal to which at least one of a power supply potential and an AC voltage for driving the resonator is applied; a first switching unit that switches modes of electrical connection between the first terminal and the third terminal; a second switching unit that switches modes of electrical connection between the second terminal and the fourth terminal; and a control unit that controls the first switching unit and the second switching unit in a first mode and a second mode, wherein in the first mode, the first terminal and the third terminal are electrically connected to each other by the first switching unit and the second terminal and the fourth terminal are electrically connected to each other by the second switching unit, in the second mode, the first terminal and the third terminal are electrically disconnected by the first switching unit and the second terminal and the fourth terminal are electrically disconnected by the second switching unit, the first mode is an inspection mode having an irregular oscillation, the second mode provides a regular oscillation, and the control unit switches the mode from the second mode to the first mode, based on a clock signal input in a period in which the supplied power supply potential is equal to or greater than a reference value. ### Claim 2 (depends on 1) The oscillation circuit according to claim 1, wherein the third terminal is a terminal connected to an earth potential. ### Claim 3 (depends on 1) The oscillation circuit according to claim 1, wherein the first switching unit is a circuit including a function of protecting the oscillation unit from a voltage higher than a maximum voltage applied to the first terminal in a state where the oscillation unit is operated. ### Claim 4 (depends on 1) The oscillation circuit according to claim 1, wherein the second switching unit is a circuit including a function of protecting the oscillation unit from a voltage higher than a maximum voltage applied to the second terminal in a state where the oscillation unit is operated. ### Claim 5 (depends on 1) The oscillation circuit according to claim 1, wherein the first terminal is electrically connected to an input terminal side of the oscillation unit. ### Claim 6 (depends on 1) The oscillation circuit according to claim 1, wherein the first switching unit includes a transistor. ### Claim 7 (depends on 1) The oscillation circuit according to claim 1, wherein the second switching unit includes a transistor. ### Claim 8 (depends on 1) An oscillator comprising: the oscillation circuit according to claim 1; and the resonator. ### Claim 9 (depends on 8) The oscillator according to claim 8, further comprising: a package which accommodates the oscillation circuit and the resonator. ### Claim 10 (depends on 1) An electronic device comprising the oscillation circuit according to claim 1. ### Claim 11 (depends on 1) A moving object comprising the oscillation circuit according to claim 1. ### Claim 12 A manufacturing method of an oscillator, comprising: preparing a configuration including an oscillation circuit including an oscillation unit that includes a first terminal and a second terminal connected to a resonator, a third terminal, a fourth terminal to which a power supply potential is applied, a first switching unit that switches modes of electrical connection between the first terminal and the third terminal, a second switching unit that switches modes of electrical connection between the second terminal and the fourth terminal, a control unit that controls the first switching unit and the second switching unit in a first mode and a second mode, and the resonator, in which the oscillation unit and the resonator are electrically connected to each other, wherein, in the first mode, the first switching unit is switched so as to electrically connect the first terminal and the third terminal to each other and the second switching unit is switched so as to electrically connect the second terminal and the fourth terminal to each other; applying an AC voltage to the third terminal and the fourth terminal; and switching, by the control unit, from the first mode to the second mode, wherein in the second mode, the first switching unit electrically disconnects the first terminal and the third terminal, and the second switching unit electrically disconnects the second terminal and the fourth terminal, wherein: the first mode is an inspection mode having an irregular oscillation, the second mode is a non-inspection mode having a regular oscillation, and the control unit switches the mode from the second mode to the first mode, based on a clock signal input in a period in which the supplied power supply potential is equal to or greater than a reference value. ### Claim 13 (depends on 12) The manufacturing method of an oscillator according to claim 12, wherein the AC voltage applied to the third terminal and the fourth terminal is at least one of a voltage for overdrive inspection and a voltage for drive level inspection.