| US 7,579,917 B2 | ||
| Output circuit for oscillator | ||
| Motoki Sakai, Kanagawa (Japan); Hisato Takeuchi, Kanagawa (Japan); Keigo Shingu, Tokyo (Japan); and Kei Nagatomo, Kanagawa (Japan) | ||
| Assigned to Panasonic Corporation, Osaka (Japan) | ||
| Filed on Mar. 23, 2007, as Appl. No. 11/727,096. | ||
| Claims priority of application No. 2006-080575 (JP), filed on Mar. 23, 2006. | ||
| Prior Publication US 2007/0236302 A1, Oct. 11, 2007 | ||
| Int. Cl. H03B 5/36 (2006.01); H03L 5/00 (2006.01) | ||
| U.S. Cl. 331—74 [331/158; 331/182] | 3 Claims |
| 2. A crystal oscillator formed by connecting an output terminal of an oscillator having a quartz vibrator to an oscillation
output terminal through a buffer circuit, wherein a switch is connected to a part of the buffer circuit which changes oscillation
characteristics, the crystal oscillator comprising a shift control unit for controlling the turning on/off of the switch,
wherein an output terminal of the oscillator having the quartz vibrator is connected to an input terminal of an inverter,
an output terminal of which is connected to a first resistor and one terminal of a second resistor,
wherein the other terminal of the first resistor is connected to one terminal of a first capacitor and an input terminal of
a first transistor,
wherein the other terminal of the first capacitor is connected to one terminal of a first switch,
wherein the other terminal of the switch is grounded,
wherein the other terminal of the second resistor is connected to one terminal of a second capacitor, an input terminal of
a second transistor, and an input terminal of a third transistor,
wherein the other terminal of the second capacitor is connected to one terminal of a second switch,
wherein the other terminal of the second switch is grounded,
wherein an output terminal of a third transistor is connected to one terminal of the third switch,
wherein the other terminal of the third switch, an output terminal of the first transistor, and an output terminal of the
second transistor are connected to the oscillation output terminal, and
wherein the first switch, the second switch, and the third switch are controlled by the shift control unit.
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