1. A power amplifier comprising:
an amplifier transistor having a collector;
a bias circuit supplying bias current to the amplifier transistor; and
a collector voltage terminal connected to the collector of the amplifier transistor, wherein the bias circuit includes:
a reference voltage terminal into which a reference voltage is input,
a power terminal connected to a power source,
a transistor having a control terminal connected to the reference voltage terminal, a first terminal connected to the power terminal, and a second terminal that is grounded, the transistor supplying a bias current corresponding to the reference voltage to the amplifier transistor,
a variable capacitor connected between the first terminal of the transistor and a grounding point, and
a logic circuit controlling capacitance of the variable capacitor, and, when a collector voltage supplied to the collector voltage terminal is higher than a prescribed voltage, the logic circuit increases the capacitance of the variable capacitor to be larger than when the collector voltage is not higher than the prescribed voltage.
2. The power amplifier according to claim 1, wherein,
when the collector voltage is higher than the prescribed voltage, the logic circuit outputs a high voltage,
when the collector voltage is not higher than the prescribed voltage, the logic circuit outputs a low voltage, and
the variable capacitor has an anode that is grounded and a cathode connected to an output of the logic circuit and connected to the first terminal of the transistor.
3. A power amplifier comprising:
an amplifier transistor having a collector;
a bias circuit supplying bias current to the amplifier transistor; and
a collector voltage terminal connected tom the collector of the amplifier transistor, wherein the bias circuit includes:
a reference voltage terminal into which a reference voltage is input,
a power terminal connected to a power source
a transistor having a control terminal connected to the reference voltage terminal, a first terminal connected to the power terminal, and a second terminal that is grounded, the transistor supplying a bias current corresponding to the reference voltage to the amplifier transistor, and
a variable resistor connected between the power terminal and the first terminal of the transistor, and
a logic circuit controlling resistance of the variable resistor, and, when a collector voltage supplied to the collector voltage terminal is higher than a prescribed voltage, the logic circuit increases the resistance of the variable resistor to be larger when the collector voltage not higher than the prescribed voltage.
4. A power amplifier comprising:
an amplifier transistor having a collector;
a bias circuit supplying bias current to the amplifier transistor;
a collector voltage terminal connected to the collector of the amplifier transistor;
a variable capacitor connected between an output terminal of the transistor and a grounding point; and
a logic circuit controlling capacitance of the variable capacitor, wherein, when a collector voltage supplied to the collector voltage terminal is higher than a prescribed voltage, the logic circuit decreases the capacitance of the variable capacitor to be lower than when the collector voltage is not higher than the prescribed voltage.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A method of controlling oxygen inhaling through an involuntary action of a user, comprising the steps of:
(a) generating a yawning influence signal periodically;
(b) applying said yawning influence signal through a media to said user; and
(c) contagiously stimulating said user to generate a sense of yawn by means of reflex action.
2. The method, as recited in claim 1, wherein said yawning influence signal is a yawning sound signal to create a yawning environment for influencing said user to generate said sense of yawn.
3. The method, as recited in claim 1, wherein said yawning influence signal is a yawning image signal to create an eye contact for stimulating said user to generate said sense of yawn.
4. The method, as recited in claim 1, wherein said yawning influence signal contains a yawning sound signal and a yawning image signal to create a yawning environment with an eye contact for stimulating said user to generate said sense of yawn.
5. The method as recited in claim 1, in step (1), further comprises a step of setting a time interval for generating said yawning influence signal in cycle.
6. The method as recited in claim 2, in step (1), further comprises a step of setting a time interval for generating said yawning influence signal in cycle.
7. The method as recited in claim 3, in step (1), further comprises a step of setting a time interval for generating said yawning influence signal in cycle.
8. The method as recited in claim 4, in step (1), further comprises a step of setting a time interval for generating said yawning influence signal in cycle.
9. The method, as recited in claim 1, wherein said yawning influence signal is transmitted through a public communication system as said media.
10. The method, as recited in claim 2, wherein said yawning influence signal is transmitted through a public communication system as said media.
11. The method, as recited in claim 3, wherein said yawning influence signal is transmitted through a public communication system as said media.
12. The method, as recited in claim 4, wherein said yawning influence signal is transmitted through a public communication system as said media.
13. An oxygen inhaling control system for a user, comprising:
a yawning influence signal; and
means for storing said yawning influence signal, wherein said storing means is capable of being converted said yawning influence signal to a human receivable signal through a media so as to contagiously stimulate said user to generate a sense of yawn by means of reflex action.
14. The oxygen inhaling control system, as recited in claim 13, wherein said yawning influence signal is a yawning sound signal to create a yawning environment for influencing said user to generate said sense of yawn.
15. The oxygen inhaling control system, as recited in claim 13, wherein said yawning influence signal is a yawning image signal to create an eye contact for stimulating said user to generate said sense of yawn.
16. The oxygen inhaling control system, as recited in claim 13, wherein said yawning influence signal contains a yawning sound signal and a yawning image signal to create a yawning environment with an eye contact for stimulating said user to generate said sense of yawn.
17. The oxygen inhaling control system, as recited in claim 13, wherein said yawning influence signal is stored in said storing means in a predetermined sequence manner that said yawning influence signal is periodically generated for applying to said user through said media with a predetermined time interval.
18. The oxygen inhaling control system, as recited in claim 14, wherein said yawning influence signal is stored in said storing means in a predetermined sequence manner that said yawning influence signal is periodically generated for applying to said user through said media with a predetermined time interval.
19. The oxygen inhaling control system, as recited in claim 15, wherein said yawning influence signal is stored in said storing means in a predetermined sequence manner that said yawning influence signal is periodically generated for applying to said user through said media with a predetermined time interval.
20. The oxygen inhaling control system, as recited in claim 16, wherein said yawning influence signal is stored in said storing means in a predetermined sequence manner that said yawning influence signal is periodically generated for applying to said user through said media with a predetermined time interval.