Seiko Epson Corporation

Tadao Kadowaki

Shinji Nakamiya

Yoshiki Makiuchi

Hiroshi Yabe

Teruhiko Fujisawa

Osamu Shinkawa

Akihiko Ebina

Masayuki Yamaguchi

Yoko Sato

This invention relates to a crystal oscillation circuit that oscillates stably with a low power consumption. This crystal oscillation circuit comprises an inverting amplifier, a crystal oscillator, and a feedback circuit that inverts the phase of an output from this inverting amplifier and feeds it back as an input. The sum of the absolute value of the threshold voltage of a first semiconductor switching element and the absolute value of the threshold voltage of a second semiconductor switching element is set to be greater than or equal to the absolute value of the potential difference between first and second potentials, when said inverting amplifier includes the first and second semiconductor switching elements.

Oscillation circuit, electronic circuit using the same, and semiconductor device, electronic equipment, and timepiece using the same

A constant-voltage generation circuit creates a constant voltage. This constant-voltage generation circuit comprises a first voltage creation circuit for creating a reference voltage and a second voltage creation circuit for creating the constant voltage which has a predetermined relationship with the reference voltage. The first voltage creation circuit comprises a first constant-current source - for supplying a constant current and a first voltage-control transistor through which this constant current flows, for outputting the reference voltage on the basis of a predetermined potential. The constant current is set to a value within the saturated operating region of the first voltage control transistor

Electronic circuit, semiconductor device, electronic equipment, and timepiece

A semiconductor integrated circuit comprising: a first power line which supplies a first voltage potential; a second power line which supplies a second voltage potential that is lower than the first voltage potential; a voltage regulator circuit connected electrically to the first and second power lines; a third power line which supplies a constant voltage generated by a voltage regulator circuit, with reference to the first voltage potential; and an operating circuit connected electrically to the first and third power lines. At least one transistor configuring the voltage regulator circuit is a partially-depleted SOI field-effect transistor in which a body region and a source region are connected electrically. At least one transistor configuring the operating circuit is a partially-depleted SOI field-effect transistor in which a body region is in an electrically floating state.

Operating circuit with voltage regular circuit having at least a partially depleted soi field effect transistor

An oscillation circuit including a first electrostatic protection circuit connected between a signal path of the oscillation circuit and a constant-voltage side, and bypassing an electrostatic voltage of a first polarity that intrudes into the signal path to a side of a constant bypass voltage through a first semiconductor rectifier element. A second electrostatic protection circuit is connected between the signal path and a reference potential side, and bypassing an electrostatic voltage of a second polarity that intrudes into the signal path to the reference potential side through a second semiconductor rectifier element. The constant bypass voltage is set to a value such that the first and second semiconductor rectifier elements are not turned on by voltage change in the signal path caused by a leakage current, even when a leakage current is generated between the signal path and a power-supply voltage line.

Oscillation circuit and electronic circuit, and semiconductor device, timepiece and electronic equipment provided with the same

A power supply apparatus employs a unidirectional unit equipped with a diode, a bypass switch connected in parallel to the diode, and a controller which turns the bypass switch ON when a forward voltage appears in the diode in order to rectify or prevent the backflow of the power from a power generating unit built in portable electronic equipment of an arm-worn type or the like; it is able to eliminate almost all loss caused by the forward voltage at the time of power supply. The elctromotive force of the power generating unit incorporated in arm-worn type electronic equipment ranges from almost the same level to about a few times the level of the forward voltage; hence, the use of the unidirectional unit enables rectifying efficiency to be markedly improved.

Power supply apparatus with unidirectional units

A constant-voltage generation circuit is provided which creates a constant voltage. The constant-voltage generation circuit may consist of a first voltage creation circuit for creating a reference voltage and a second voltage creation circuit for creating a constant voltage which has a predetermined relationship with the reference voltage. The first voltage creation circuit may consist of a constant-current source for supplying a constant current and a voltage-control transistor through which this constant current flows, for outputting the reference voltage on the basis of a predetermined potential. The constant current is set to a value within the saturated operating region of the voltage-control transistor.

A crystal oscillation circuit that is capable of operating stably with a low power consumption includes a signal inversion amplifier and a power control circuit that controls the power voltage of this signal inversion amplifier in accordance with an oscillation output. The power control circuit includes a power voltage generation circuit that outputs a plurality of power voltages of different values; a determination control portion that determines the optimal value of the power voltage to be applied to the signal inversion amplifier, based on the oscillation output; and a multiplexer that controls the switching of the power voltage applied to the signal inversion amplifier from the power voltage generation circuit, based on the result of that determination.

Oscillator circuit supplied with optimal power voltage according to

An oscillation circuit including an electrostatic protective circuit connected between a signal path and this constant voltage V.sub.reg. It comprises a first electrostatic protective circuit portion that causes any electrostatic voltage of a first polarity that invades the signal path to be selectively diverted through a diode to the constant voltage V.sub.reg side of the circuit, and any electrostatic voltage of a second polarity that invades the signal path to be selectively diverted through another diode to the ground side. This ensures that the oscillation circuit is not affected by fluctuations in the power voltage from the main power source, enabling it to oscillate at a stable frequency.

Oscillation circuit having electrostatic protective circuit

Crystal oscillator circuit having transistor with back gate voltage

A crystal oscillation circuit that oscillates stably with a low power consumption includes an inverting amplifier, a crystal oscillator, and a feedback circuit that inverts the phase of an output from this inverting amplifier and feeds it back as an input. The inverting amplifying includes first and second semiconductor switching elements. The sum of the absolute value of the threshold voltage of the first semiconductor switching element and the absolute value of the threshold voltage of the second semiconductor switching element is set to be greater than or equal to the absolute value of the potential difference between first and second potentials, in order to prevent the first and second semiconductor switching elements from being on simultaneously.

Growing community of inventors

Chino, Japan

Tadao Kadowaki