JPH0946135A - Multi-channel changeover oscillation circuit and coordinate entry device using the circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost and power consumption by connecting either one of frequency setting elements used to be connected at a different setting frequency to set an oscillating frequency of an oscillating element within a prescribed range to the oscillating element depending on a setting signal. SOLUTION: A multi-channel switching oscillating circuit 21 is provided with a single oscillating element (e.g. quartz element) 22 to form a crystal oscillation circuit as a whole. As frequency setting elements 231 -23n . connected electrically to the oscillation element 22 to decide the oscillating frequency, each capacitor with a capacitance in response to a setting frequency is used and either one of the frequency setting elements 231 -23n is connected electrically to the oscillation element 22 by a selection means 24. Then the selection means 24 makes electric connection in response to setting signals D1 , D2 ,..., Dn to be received. Thus, it is not required to provide the oscillating element in response to each different oscillating frequency and low cost and power saving are attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-channel switching oscillator circuit for outputting multi-channel oscillation signals having different oscillation frequencies and a coordinate input device using the same.

[0002]

2. Description of the Related Art In recent years, the processing capability of an information processing device has been dramatically improved and the operation has been complicated, and a coordinate input device called a mouse is used to improve operability. Programs that perform operations have become widespread. This mouse was used by connecting it to a host device by a cord, but recently, a wireless mouse without the cord has appeared.

Here, FIG. 6 shows a conceptual diagram of a conventional wireless mouse. The mouse 11 shown in FIG. 6 has, for example, two switches (right switch, left switch) 11a, 11b formed in the same shape as those for performing cord connection, and the antenna 12 is used in place of the connection cord. It is provided. In addition, the antenna 12 is the mouse 1
Some are built into 1. Then, the radio wave of the coordinate position signal is transmitted from the antenna 12 to the host device 13 such as a personal computer, and the host device 13 takes in the received coordinate position signal as an input signal.

Further, depending on the usage environment, there may be a case where a plurality of mice 12 corresponding to a plurality of host devices 13 are used in the vicinity. Therefore, by selecting one channel as a multi-channel transmission of the mouse 12. Prevents interference. Therefore, FIG. 7 shows a block diagram of a main part of the wireless mouse of FIG. Figure 7 shows a wireless mouse 1
The block diagram of the transmission part in the component of 1 is shown, and in this example, the case where 2 channels are switched is shown. In FIG. 7, the oscillator 1 including the modulation circuit 14a
4 is input to the mixer 15, and the mixer 15 is further divided into first and second oscillators 16 for two channels.
The respective outputs of 17 are switched by the switch means 18 and input. The output of the mixer 15 is transmitted from the antenna 12 via the amplifier 19.

In this case, the oscillating unit 14 and the first and second oscillators 16 and 17 generally have a quartz element built therein to perform crystal oscillation in order to make the oscillation frequency highly accurate. For example, when the first oscillator 16 is selected by the switch means 18, the carrier of the oscillation frequency f ₀ on which the modulated position data from the oscillator 14 is superimposed and the oscillation frequency f ₁ from the first oscillator 16 are selected. The carrier wave (transmission frequency) is mixed by the mixer 15, further amplified and filtered by the amplifier 19, and transmitted from the antenna 12. The same applies when the second oscillator (oscillation frequency f ₂ ) 17 is selected by the switch means 18.

Here, FIG. 8 shows a waveform diagram of the deviation of the oscillation frequency of FIG. As described above, the first and second oscillators 1
6 and 17 use a quartz element, and one oscillation frequency is set within the range of the shift width t as the oscillation frequency generated by this quartz element. Therefore, the oscillation frequency f ₁ as the transmission frequency of the first oscillator 16 is set within the range of the shift width t of the oscillation frequencies f ₁₁ and f ₁₂ , and the oscillation frequency f ₂ (as the transmission frequency of the second oscillator 17 ( (differs from f ₁ ) is set within the range of the shift width t of the oscillation frequencies f ₂₁ and f ₂₂ .

[0007]

However, when the wireless mouse 11 has multiple channels as described above, and the wireless mouse 11 has two channels as shown in FIG. 7, the oscillator 1 is used.
4, three crystal oscillating circuits are required in the first and second oscillators 16 and 17, and the crystal oscillating circuits have to be increased every time the number of channels is increased. There is a problem that power consumption increases according to the number.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a multi-channel switching oscillation circuit and a coordinate input device for reducing the cost and saving the power.

[0009]

In order to solve the above-mentioned problems, in a first aspect of the present invention, a single oscillating element capable of freely generating an oscillating frequency within a predetermined width and a range of the predetermined width of the oscillating element are provided. A plurality of frequency setting elements that are connected with different setting values to achieve a predetermined oscillation frequency and one of the frequency setting elements is electrically connected to the oscillation element according to the input of a corresponding setting signal. A multi-channel switching oscillating circuit is configured to include a selecting unit for controlling the oscillating circuit.

In this multi-channel switching oscillator circuit, one of the frequency setting elements is electrically connected to the oscillation element to obtain a desired oscillation frequency, which is selected by the selecting means. Since it is not necessary to provide an oscillating element, cost reduction and power saving can be achieved.

According to a second aspect of the present invention, the detecting means for detecting the coordinate position, the position signal generated by the signal from the detecting means and output, and the setting signal for determining the transmission frequency generated based on the input signal are output. And a multi-channel switching oscillation circuit according to claim 1, wherein a transmission frequency is set according to a setting signal from the control means, and a position signal from the control means is modulated to set the transmission frequency. The coordinate input device is configured to include a transmitting unit that wirelessly transmits.

In this coordinate input device, when setting the transmission frequency of a predetermined channel, the control means sends a setting signal according to the input signal to the multi-channel switching oscillator circuit of the transmitting means, and the transmitting means sends the setting signal. The position signal modulated at the transmission frequency set in step 1 is transmitted wirelessly. As a result, it is not necessary to provide a plurality of oscillation circuits having oscillation elements corresponding to different transmission frequencies, and it is possible to achieve cost reduction and power saving.

[0013]

1 is a block diagram of a multi-channel switching oscillator circuit according to a first embodiment of the present invention. The multi-channel switching oscillator circuit 21 shown in FIG.
2 is provided and, for example, a quartz element is used to form a crystal oscillation circuit as a whole. On the other hand, first to first electrically connected to the oscillation element 22 to determine the oscillation frequency
The n-th frequency setting elements 23 ₁ to 23 _n are provided and, for example, capacitors each having a capacity corresponding to the set frequency are used.

The first to nth frequency setting elements 23 ₁ to
Any one of 23 _n is electrically connected to the oscillating element 22 by the selecting means 24, and the selecting means 24 is electrically connected according to the corresponding setting signal (D ₁ , D ₂ ... D _n ). Make a connection. The selecting means 24 is composed of, for example, a transistor. The specific circuit will be described with reference to FIG.

Therefore, the oscillating element 22 is
1 to n-th frequency setting elements 23 ₁ to 2 2 electrically connected by the selecting means 24 within the range of deviation of the oscillation frequency.
It outputs signals of oscillation frequencies f ₁ , f ₂ ... F _n according to any of 3 _n . In this way, the first to nth frequency setting elements 23 ₁ connected by the single oscillation element 22
It is possible to obtain an oscillation frequency according to ˜23 _n , and it is not necessary to provide an oscillating element corresponding to a different oscillation frequency, so that cost reduction and power saving can be achieved.

Next, FIG. 2 shows a block diagram of a coordinate input device according to a second embodiment of the present invention. FIG. 2A shows a wireless mouse 31 as a coordinate input device, and the transmission destination is a host device such as the personal computer as shown in FIG. The wireless mouse 31 shown in FIG.
Is an X encoder 32 and a Y encoder for detecting the position in the X-axis direction.
Equipped with a Y encoder 33 for detecting the axial position, each X
The detection signals of the encoder 32 and the Y encoder 33 are calculated by the comparator 34 and sent to the microcomputer 35 which is the control means. The X encoder 32, the Y encoder 33, and the comparator 34 constitute a detecting means.

The microcomputer 35 sends an ST signal to the transmission module 36.
A ROVE signal and various types of DATA are transmitted, the transmission module 36 performs various processes such as modulation for transmission, and the signals are transmitted from the antenna 37. The multi-channel switching oscillation circuit 21 described above is provided in the transmission module 36. Further, switches (LSW, RSW) 38a, 3 for causing the microcomputer 35 to input a signal from the outside (operator).
8b is connected. Then, power is supplied from the power source (+ B) 39 to each necessary component.

FIG. 2B shows an internal block diagram of the transmission module 36, which is roughly divided into a multi-channel switching oscillator circuit 21 and an amplifier 40. The multi-channel switching oscillation circuit 21 is configured to include an oscillation circuit 41 having a quartz element incorporated therein, a modulation circuit 42, a channel switching circuit 43, and the like. Further, the amplification section 40 is configured to include an amplifier, a filter, and the like.

Therefore, FIG. 3 shows a specific circuit diagram of FIG. 2 (B). The oscillation circuit 41, the modulation circuit 42, and the channel switching circuit 43 in the multi-channel switching oscillation circuit 21 in FIG. 3 are not particularly distinguished, and are shown as an example of two channels.

In FIG. 3, a PNP type transistor is connected to the power source + B.
Langista Q₁Through the power supply voltage V _ccWith multiple channels
Power is supplied to the replacement oscillator circuit 21, and the transistor Q
₁Is an NPN transistor Q₂By the operation of
The base is driven between (ground) and the transistor Q₂Is
Driven by the STROVE signal from the microcomputer 35
You. This STROVE signal is a multi-channel switching oscillator circuit.
This is a signal for instructing 21 to supply power. In addition,
Source voltage V_CCSmoothing capacitor C between GND and GND₁Is connected
You.

On the other hand, in the multi-channel switching oscillating circuit 21, the emitters are connected to the power supply voltage V _CC , respectively.
A transistor Q ₅ composed of NP type transistors Q ₅₁ and Q ₅₂ , wherein the base of the transistor Q ₅₁ is supplied with a signal of DATA1 from the microcomputer 35, and the base of the transistor Q ₅₂ is supplied with a signal of DATA 2 from the microcomputer 35. To be done. NPN type transistors Q ₆₁ and Q which form a transistor Q ₆ from the collector of the transistor Q ₅₂
Bias to ₆₂ bases respectively. The emitters of the transistors Q ₆₁ and Q ₆₂ are connected to GND.

The collectors of the transistors Q ₆₁ and Q ₆₂ are connected to one end of the inductor L1 through a parallel circuit of the variable capacitor CT2 and the capacitor C7. Also, the transistor Q that constitutes the transistor Q ₅
One of the inductors L1 is biased from the collector of _{51 to} the bases of NPN type transistors Q ₇₁ and Q ₇₂ which form the transistor Q _7, and the collector of each of the transistors Q ₇₁ and Q ₇₂ is connected to the inductor C1 via the capacitor C8. Connected to the end. The connected emitters of the transistors Q ₇₁ and Q ₇₂ are connected to GND.

The other end of the inductor L1 is the quartz element X1.
The other end of the quartz element X1 is connected to one end of the quartz element X1 and biases the base of an NPN transistor Q3 through a parallel circuit of a variable capacitor CT1 and a capacitor C6.
The base of the transistor Q3 is connected to the power supply voltage V _CC via resistors R1 and R2, and is also connected to GND via capacitors C4 and C5. The emitter of the transistor Q3 is connected to the connection point of the capacitors C4 and C5, and is also connected to GND via the capacitor C10 in the amplification unit 40 via the inductor L2.

The collector of the transistor Q3 is connected to the connection point of the resistors C1 and R2 in parallel with the capacitor C3 and the inductor L3, and is also connected to GND through the capacitor C9 and the inductor L4. In addition,
The connection point of the resistors R1 and R2 is connected to GND via the capacitor C2. Capacitor C9 and inductor L4
Is connected to capacitors C12 and C1 in the amplification unit 40.
3 to the GND. This capacitor C1
The connection point of 2, C13 is connected to GND via an inductor L5.

Further, the resistor R in the amplifier 40 is connected from the emitter of the transistor Q3 via the inductor L2.
It is connected to the base of the NPN type transistor Q4 via 3, R4. The base of the transistor Q4 is further connected to GND via a capacitor C15 and a parallel circuit of the capacitor 14 and the inductor L6.

The collector of the transistor Q4 is connected to the connection point of the resistors R3 and R4 via the inductor L7, and the capacitor C17, the antenna 37 and the capacitor C are connected.
19 is sequentially connected to GND. The resistance R
GND from the connection point of 3, R4 via the capacitor C16
And is connected to GND via a capacitor C18 from the connection point between the capacitor C17 and the antenna 37.

The operation of FIG. 3 will now be described with reference to FIG. 4 which shows the signal state of the input signal of FIG. 3 and FIG. 5 which shows the waveform diagram of the deviation of the oscillation frequency of FIG. First, the power supply voltage _Vcc is supplied to the multi-channel switching oscillation circuit 21 by the STROVE signal from the microcomputer 35, and the operation starts.

When the microcomputer 35 selects channel 1, for example, DATA2 is supplied as "H" (V _cc ) as shown in FIGS. 4A and 4B, and DATA is supplied.
1 to supply the data signal. DATA2 is now "H"
In this state, the transistor Q6 is turned off and the capacitors CT2 and C7 are opened. Also, D
When the data signal of ATA1 changes between the "L" state and the "H" ( _Vcc ) state, the transistor Q7 changes between the on state and the off state, which causes the capacitor C8 to turn on. And between off states.
That is, the oscillation frequency of the quartz element X1 is determined by the capacitances of the capacitors CT1 and C6 and the capacitance of the capacitor C8 in the channel 1, and within the range of the deviation width t in the oscillation of the quartz element X1 as shown in FIG. Is determined between the oscillation frequencies f ₃₁ and f ₃₂ .

On the other hand, when the microcomputer 35 selects the channel 2, as shown in FIGS. 4 (A) and 4 (B), the DAT
A1 is brought to the "L" state, and a data signal is supplied to DATA2. When DATA1 is in the "L" state, the transistor Q
7 is turned on, and the capacitor C8 is grounded. When the data signal of DATA2 changes between the "L" state and the "H" state, the transistor Q6 changes between the ON state and the OFF state, whereby the capacitors CT2 and C7 are turned on. Change between off and on.

That is, the oscillation frequency of the quartz element X1 is the same as the capacitors CT1 and C in the channel 2.
6 and the capacitances of capacitors CT2, C7 and C8. Therefore, as shown in FIG. 5, within the range of the shift width t in the oscillation of the quartz element X1, the oscillation frequency f ₃₂
And f ₃₃ . Thus, the oscillation frequency is switched by switching the ground capacitance of the quartz element X1 by switching the channel. In the case of three or more channels, switching transistors and capacitors associated therewith may be provided according to the number of channels.

As described above, a single quartz element X
Since one can obtain multi-channel oscillation frequencies, three oscillation circuits, which were required in the case of two channels as shown in the prior art (FIG. 7), can be configured by one oscillation circuit. No conventional mixer is required.
Therefore, it is possible to reduce the cost and save power.

The multi-channel switching oscillator circuit 21 (specific circuit diagram is FIG. 3) shown in FIG. 1 is a wireless mouse 31.
However, the present invention can be applied to all devices that perform multi-channel transmission and reception.

[0033]

As described above, according to the invention of claim 1,
Since any one of the frequency setting elements is electrically connected to the oscillating element and the desired oscillating frequency is obtained by the selecting means, it is not necessary to provide oscillating elements corresponding to different oscillating frequencies, and the cost is reduced. In addition, power saving can be achieved.

According to the second aspect of the present invention, when the transmission frequency of the predetermined channel is set, the control means sends a setting signal corresponding to the input signal to the multi-channel switching oscillation circuit of the transmission means, and the transmission means By wirelessly transmitting the position signal modulated at the transmission frequency set by the setting signal,
Since it is not necessary to provide a plurality of oscillation circuits having oscillation elements corresponding to different transmission frequencies, cost reduction and power saving can be achieved.

[Brief description of drawings]

FIG. 1 is a block diagram of a multi-channel switching oscillator circuit according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a coordinate input device according to a second embodiment of the present invention.

FIG. 3 is a specific circuit diagram of FIG. 2 (B).

FIG. 4 is an explanatory diagram of a signal state of the input signal of FIG.

FIG. 5 is a waveform diagram of the deviation of the oscillation frequency of the present invention.

FIG. 6 is a conceptual diagram of a conventional wireless mouse.

7 is a block diagram of a main part of the wireless mouse of FIG.

FIG. 8 is a waveform diagram of deviation of the oscillation frequency of FIG.

[Explanation of symbols]

21 multi-channel switching oscillation circuit 22 oscillation element 23 ₁ to 23 _n frequency setting element 24 selecting means 31 wireless mouse 35 microcomputer 36 transmission module 37 antenna 41 oscillation circuit 42 modulation circuit 43 channel switching circuit

Claims (2)

[Claims] 1. A single oscillating element capable of freely generating an oscillating frequency with a predetermined width, and a plurality of connected with different set values for setting a predetermined oscillating frequency within the predetermined width of the oscillating element. 2. The channel switching oscillator circuit according to claim 1, further comprising: a frequency setting element; 2. A detecting means for detecting a coordinate position, and a control means for generating and outputting a position signal by a signal from the detecting means and outputting a setting signal for determining a transmission frequency generated based on an input signal. And a multi-channel switching oscillator circuit according to claim 1, wherein a transmission frequency is set in accordance with a setting signal from the control means, a position signal from the control means is modulated, and the set transmission frequency is wirelessly transmitted. A coordinate input device comprising: a transmitting means for transmitting.