JP2007189284A - Board for oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a board for an oscillator using printed resistors sharable with a VCXO and a PXO. <P>SOLUTION: The board for the oscillator is usable for the PXO comprising a crystal resonator Y1 and a crystal oscillation circuit 11 or for a VCXO comprising a piezoelectric oscillation circuit and a frequency voltage control circuit 12, and resistive components of the VCXO employ the printed resistors except a resistor R2 which is replaced with a short-circuit component to change the VCXO into the PXO. Since the board 21 for the oscillator can be used in common between the VCXO and the PXO in this way, a cost-reduced oscillator can be obtained. Further, since the resistors except the resistor R2 for changing the VCXO into the PXO employ the printed resistors, it is possible to downsize the piezoelectric oscillator. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an oscillator substrate that can be used in a piezoelectric oscillator or a voltage-controlled piezoelectric oscillator.

Conventionally, in various electronic devices such as a mobile phone, a crystal oscillator (PXO) using a piezoelectric element and a voltage controlled crystal oscillator (VCXO) are used.
tor) is widely used.
Patent Document 1 discloses a variable frequency oscillation in which a piezoelectric vibrator and a variable capacitance diode connected to an oscillation circuit and a circuit network in which an inductance and a capacitance are connected in parallel are arranged in series so as to expand a frequency variable range with respect to voltage. A circuit is disclosed.
JP 2001-16039 A

By the way, in the above-described crystal oscillator (hereinafter referred to as PXO) and voltage controlled crystal oscillator (hereinafter referred to as VCXO), further downsizing and cost reduction are required.
In order to realize an ultra-small size oscillator having a package size of 7 [mm] × 5 [mm] or less, which will become the mainstream in the future, it is necessary to further reduce the size of the components constituting the circuit.
As one means for reducing the size of the crystal oscillator, it can be considered that the resistance of the oscillation circuit is formed on the mounting substrate by a printing resistor. On the other hand, as a means for realizing the cost reduction of the crystal oscillator, for example, it is conceivable to reduce the cost by increasing the number of mass production by sharing the substrate for VCXO also in PXO. In other words, if a mounting board that can be used for both VCXO and PXO can be manufactured by forming a resistor by printing resistance, PXO and V
Thus, the CXO can be reduced in size and cost.
However, when all the resistors are formed by printing resistors in order to reduce the size, there is a drawback that an oscillator substrate that can be shared by PXO and VCXO cannot be manufactured due to the circuit configuration.
The present invention has been made in view of such a point, and an object thereof is to provide an oscillator substrate using a printing resistor that can be shared by VCXO and PXO.

In order to achieve the above object, the present invention relates to an oscillator usable for a piezoelectric oscillator composed of a piezoelectric vibrator and an oscillation circuit, or a voltage controlled piezoelectric oscillator composed of a piezoelectric oscillation circuit and a frequency voltage control circuit. Among the resistance components that constitute the voltage-controlled piezoelectric oscillation circuit,
Other than the resistance component that can change the voltage-controlled piezoelectric oscillator to a piezoelectric oscillator by replacing the short-circuit component, a printing resistor was used. With this configuration, one oscillator substrate can be shared between the VCXO and the PXO, so that the cost of the piezoelectric oscillator can be reduced. In addition, the piezoelectric oscillator can be reduced in size because the printing resistor is used to form components other than the resistance component for changing VCXO to PXO.
Further, the present invention is configured such that an IC that constitutes an ECL circuit that converts the oscillation output of the oscillation circuit into a digital output and outputs the digital output can be mounted. With this configuration, it is possible to configure a VCXO and a PXO that can output a single oscillator substrate digital signal. In addition, since an IC chip can be mounted on the printed resistor, it is possible to reduce the size and cost of a crystal oscillator capable of digital output.

Hereinafter, embodiments of the oscillator substrate of the present invention will be described. In the present embodiment, a case where a crystal resonator is used as a piezoelectric element will be described as an example.
FIG. 1 shows a voltage controlled piezoelectric oscillator (VCXO) constituted by the oscillator substrate of the present embodiment.
FIG.
The VCXO shown in FIG. 1 includes a Colpitts type crystal oscillation circuit 11 and a frequency voltage control circuit 1.
2. The crystal oscillation circuit 11 has a crystal resonator Y1 at the base of the transistor Q1.
Is connected to a base bias circuit composed of resistors R4 and R5, and further connected to a series circuit of capacitors C1 and C2 serving as part of the load capacitance between the base and the ground. . The connection midpoint of this series circuit is connected to the connection point between the emitter of the transistor Q1 and the resistor R7. The collector of the transistor Q1 is connected to the power supply Vcc via the collector resistor R6. Capacitors C10 and C11 are noise removal bypass capacitors.

A frequency voltage control circuit 12 is connected to the other end of the crystal unit Y1. The frequency voltage control circuit 12 includes a parallel circuit of a capacitor C5 and a capacitor C6, a resistor R3 and an inductor L
1 and a series circuit in which a resistor R2 is connected in series. One end of the parallel circuit of the capacitor C5 and the capacitor C6 is connected to the other end of the crystal resonator Y1, and one end of the resistor R2 is grounded. I have to. Further, a first parallel circuit in which a capacitor C4 and a variable capacitance diode D2 are connected in parallel and a capacitor C3 and a variable capacitance diode D1 are connected in parallel between a connection point between the resistor R3 and the resistor R2 and the ground. A series circuit in which the second parallel circuit is connected in series is connected.
The cathode connection points of the variable capacitance diodes D1 and D2 are connected to the control voltage terminal Vcont via the AC blocking resistor R1. Thus, the oscillation output of the crystal oscillation circuit 11 can be variably controlled by the control voltage from the control voltage terminal Vcont.

In this embodiment, in order to reduce the size of the VCXO shown in FIG.
D2 is constituted by a bare chip on the oscillator substrate, and the resistance of the VCXO is formed on the oscillator substrate by a printing resistor. At this time, there is a feature in that only the resistor R2 is not constituted by the printing resistor.
That is, in this embodiment, by replacing the resistor constituting the VCXO with a short-circuit component such as a 0Ω resistor, a resistor other than the resistor R2 that can change the VCXO to PXO is formed by a printed resistor, and the resistor R2 is a chip that is a chip component. Component electrodes are provided on the oscillator substrate so that they can be configured by resistors. As a result, the oscillator substrate of this embodiment can be used not only as the VCXO shown in FIG. 1 but also as an oscillator substrate of a crystal oscillator (PXO) as shown in FIG.

For example, when the PXO is configured by the oscillator substrate of the present embodiment, short-circuit components such as 0Ω resistors are provided on the component electrodes of the capacitor C5, the inductor L1, and the resistor R2, without mounting the variable capacitance diodes D1 and D2. If it is mounted and short-circuited, a PXO with the other end of the crystal resonator Y1 grounded can be configured.
Therefore, according to the oscillator substrate of this embodiment, VCXO and PX having the same package size are used.
Since the oscillator substrate can be used in both cases, an oscillator substrate can be realized at a low cost. In addition, since the resistors other than the resistor R2 for changing VCXO to PXO can be formed by printing resistors, the oscillator can be reduced in size.

Next, ECL (Emitter Coup) capable of digital output using the oscillator substrate of the present embodiment.
A case where a crystal oscillator including a led logic circuit is configured will be described.
FIG. 3 is a diagram illustrating a configuration of a VCXO including an ECL circuit configured using the oscillator substrate of the present embodiment, and FIG. 3A illustrates a circuit configuration of the VCXO including the ECL circuit. 3B is an external view of the oscillator substrate used in the VCXO shown in FIG.
c) is a diagram showing a state in which components are mounted on an oscillator substrate. The same circuit parts as those in FIG.

The VCXO shown in FIG. 3 inputs the output of the oscillation circuit to the ECL circuit 13 through a series circuit of the coupling capacitor C8 and the resistor R8, converts the output to a digital output by the ECL circuit 13, and outputs the digital output.
The ECL circuit 13 is configured by connecting each terminal of a differential amplifier circuit V1 constituted by an IC, a level adjusting resistor R9, and a bypass capacitor C9 as illustrated.
In the VCXO including such an ECL circuit, resistors R1, R3, R4, R5, R6, and R7 are formed on the oscillator substrate 21 by printing resistors as shown in FIG.
Accordingly, as shown in FIG. 3C, an IC chip 22 or an inductor L1 chip in which the variable capacitance diodes D1 and D2 and the differential amplifier circuit V1 are formed as one chip on the printed resistor formed on the oscillator substrate 21. The component 23 can be mounted, and the circuit can be reduced in size.

FIG. 4 is a diagram illustrating a configuration of a PXO including an ECL circuit configured using the oscillator substrate of the present embodiment, and FIG. 4A illustrates a circuit configuration of the PXO including the ECL circuit. FIG. 4B is a diagram showing a state in which components are mounted on the oscillator substrate. Note that the same components as those in FIG.
When the PXO having the ECL circuit shown in FIG. 4A is configured, components are mounted on the oscillator substrate 21 shown in FIG. 3B as shown in FIG. 4B. That is, FIG.
The chip component 24 of the capacitor C5 mounted in the VCXO shown in FIG. 5 is removed, and the chip components 26 and 27 for short-circuiting are mounted in place of the chip component 23 of the inductor L1 and the chip component 25 of the capacitor C6. Yes. If configured in this way,
A single VCXO and PXO capable of digital output can be configured with a single oscillator substrate 21. In addition, since the IC chip 22 can be mounted on the printing resistor, it is possible to reduce the size and cost of a crystal oscillator capable of digital output.

The figure which showed the circuit structure of VCXO comprised by the board | substrate for oscillators of embodiment of this invention. The figure which showed the circuit structure of PXO comprised by the board | substrate for oscillators of this embodiment. The figure which showed the structure of VCXO provided with the ECL circuit comprised using the board | substrate for oscillators of this embodiment. The figure which showed the structure of PXO provided with the ECL circuit comprised using the board | substrate for oscillators of this embodiment.

Explanation of symbols

L1 ... inductor, Q1 ... transistor, D1, D2 ... variable capacitance diode, V1 ... differential amplifier circuit, R1 ... resistor, Y1 ... crystal resonator, C1 to C11 ... capacitors C, D1, D2
... variable capacitance diodes, R1, R3, R4, R5, R6, R7 ... printing resistor, R2 ... chip resistor, 11 ... crystal oscillation circuit, 12 ... frequency voltage control circuit, 13 ... ECL circuit, 21 ... substrate for oscillator, 22 ... IC chips, 23-27 ... chip parts

Claims (2)

A substrate for an oscillator usable for a piezoelectric oscillator composed of a piezoelectric vibrator and an oscillation circuit, or a voltage controlled piezoelectric oscillator composed of the piezoelectric oscillation circuit and a frequency voltage control circuit,
For the oscillator, the resistance component constituting the voltage controlled piezoelectric oscillator is replaced by a short circuit component, and the voltage controlled piezoelectric oscillator other than the resistive component capable of changing the voltage controlled piezoelectric oscillator to the piezoelectric oscillator is formed by a printing resistor. substrate. The oscillator substrate according to claim 1,
An IC comprising an ECL circuit that converts the oscillation output of the oscillation circuit into a digital output and outputs the digital output
A substrate for an oscillator, wherein a chip can be mounted.

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