Seiko Epson Corporation

Manabu Oka

Masayuki Kikushima

Kazuhiko Shimodaira

Katsuyoshi Terasawa

Yukari Nakajima

Takashi Endo

Yugo Koyama

Kazushige Ichinose

Katsuhiko Miyazaki

Kazunari Ichinose

A piezoelectric oscillator includes: a piezoelectric resonator; a storage unit that stores temperature compensation data used for specifying frequency-temperature characteristics of the piezoelectric resonator therein; a temperature compensation circuit; a voltage-controlled oscillation circuit that oscillates the piezoelectric resonator and controls an oscillation frequency of the piezoelectric resonator based on an oscillation control voltage; and a power source control unit that controls so as to supply a power source voltage to the temperature compensation circuit or so as not to supply the power source voltage to at least a part of the temperature compensation circuit based on a control signal transmitted from the outside, wherein the temperature compensation voltage is supplied as the oscillation control voltage to the voltage-controlled oscillation circuit in synchronization with a period during which the power source voltage is supplied to the temperature compensation circuit.

Piezoelectric oscillator, GPS receiver device, and electronic apparatus

To facilitate the manufacture of an accurate receiver, a piezoelectric device manufacturer determines characteristic data, such as an approximate expression representative of a temperature characteristic of piezoelectric device and coefficients of the approximate expression, and stores it to a memory of a manufacturer's computer corresponding to a serial number of each piezoelectric device. The piezoelectric device manufacturer, ships a piezoelectric device to a vendor, transfers the characteristic data of the piezoelectric device to the vendor server through a communication network. The client, when the purchased piezoelectric device is mounted on an electronic appliance, reads out a serial number and inputs it to the client's computer. The client's computer acquires the characteristic data of the piezoelectric device corresponding to the serial number from the vendor server through the communication network, and writes it to a memory of the electronic appliance.

Method for manufacturing a receiver and receiver manufactured by using the same method

An oscillation signal that is provided from an inverter-type oscillation circuitis input to an output driving circuit. In the output driving circuit, a control circuitcontrols a voltage control circuitand a buffer circuitin accordance with control data written in a memory circuit, to generate a clock signal with control data amplitude, duty ratio, rising/falling characteristics of an output waveform in accordance with the control data. The output driving circuitis configured with a plurality of voltage control circuits and a plurality of buffer circuits to allow clock signals, each having different waveform characteristics, to be provided from a plurality of output terminals.

Oscillator and electronic device using the same

The invention provides a piezoelectric oscillator having a reduced horizontal size and capable of being mounted in a small area. The invention also provides a portable telephone and an electronic device using such a piezoelectric oscillator. The piezoelectric oscillator includes a first package and a second package which are firmly connected to each other such that the second package is located on the first package. An oscillator circuit element is disposed in the first package, and a piezoelectric resonator is disposed in the second package. The first package includes a first lead frame and a second lead frame. End parts of the first lead frame are bent downward such that the bent portions at the lower end are exposed to the outside and serve as the first connection terminals. The second lead frame is placed on the first lead frame. End parts of the second lead frame are bent upward so as to serve as second connection terminals. The first connection terminals described above are used as mounting terminals. The second connection terminals are electrically connected to external terminals of the second package.

Piezoelectric oscillator, portable telephone using a piezoelectric oscillator, and electronic device using a piezoelectric oscillator

An oscillatorincludes temperature compensation circuitsand, a frequency adjusting circuit, and an initial deviation correcting circuit. Switches SWtoare controlled based on control data DC stored in a memoryso that a temperature compensation voltage V, a temperature compensation voltage V, a frequency adjusting voltage V, and an initial deviation correcting voltage V, output from the above circuits, are selectively added, supplying a sum to a voltage-controlled oscillation circuitas a control voltage VA.

Oscillator and communication apparatus

A temperature compensated oscillator, a method of controlling a temperature compensated oscillator, and a wireless communication device are provided, where phase noise of the output signal can be reduced, frequency of the output signal stabilizes within a short time, and response of control does not become worse. Accordingly, a filter circuit is provided that removes noise contained in a temperature compensation voltage. A switching circuit is connected in parallel to this filter circuit. A power control circuit controls power supply to a voltage controlled oscillation circuit and the like. The power control circuit turns on the switching circuit for a specified period when power supply to the voltage controlled oscillation circuit is started.

Temperature compensated oscillator, method of controlling temperature compensated oscillator, and wireless communication device

A voltage-controlled piezoelectric resonator may be implemented without requiring the use of a trimmer capacitor by virtue of the use of a capacitor array with or without an additional capacitor array, thus reducing the number of external parts. The capacitor array and the additional capacitor array can be packaged in an IC, thus enabling reduction in the size of the voltage-controlled piezoelectric resonator. The voltage-controlled piezoelectric resonator incorporating the capacitor array exhibits high stability both in terms of secular change and operation, which in turn ensures high stability of operation of a piezoelectric oscillation circuit incorporating this voltage-controlled piezoelectric resonator. An oscillation center frequency adjusting mechanism produces adjusting data, so that the adjustment of the oscillation center frequency can be effected purely electrically. Since mechanical adjusting operation that is essential in conventional arrangements is unnecessary, the time required for the adjustment of the oscillation center frequency is shortened to allow a reduction in the production cost of the voltage-controlled piezoelectric resonator.

Capacitor array unit connected to oscillation circuit with a piezoelectric reasonator, capacitor array unit controller oscillation frequency adjusting system and oscillation frequency adjusting method

A voltage-controlled oscillator is provided having a semiconductor integrated circuit and a piezoelectric resonator. A variable-capacitance diode may be connected in series with the piezoelectric resonator. The variable-capacitance diode may be further mounted a land of a lead frame. The piezoelectric resonator, variable-capacitance diode and lead frame may be resin molded into a single unit. In operation, a signal may be applied to a node located between the variable-capacitance diode and the DC-cutting capacitor.

Voltage-controlled oscillator having a semiconductor integrated circuit,

This invention provides a temperature-compensated piezoelectric oscillator having an oscillation frequency that is easily adjusted in an adjustment procedure after its assembly. Compensation for frequency-temperature characteristics is achieved without the need for an externally installed variable reactance element. The temperature-compensated piezoelectric oscillator includes a piezoelectric oscillator element and an oscillator circuit that drives the piezoelectric oscillator element. The oscillator circuit changes the oscillation frequency in response to an applied power supply voltage VDD(T). A temperature sensor circuit senses the ambient temperature T of the piezoelectric oscillator element. A variable power supply circuit changes the power supply voltage VDD(T) applied to the oscillator circuit in response to the temperature sensed by the temperature sensor circuit. The changes in the applied power supply voltage VDD(T) changes the frequency-temperature characteristics of the oscillator circuit.

Temperature-compensated piezoelectric oscillator

The invention provides a piezoelectric oscillator including a semiconductor integrated circuit and a piezoelectric resonator or a voltage-controlled oscillator including a semiconductor integrated circuit, a piezoelectric resonator and another electronic component. The piezoelectric resonator has a cross-sectional shape of an ellipse or a track. The semiconductor integrated circuit and the electronic component are molded with a resin into a very thin unit.

Growing community of inventors

Minowa-machi, Japan

Manabu Oka