Radio frequency power source having precise power detector

1. A radio frequency (RF) power supply comprising:

a RF signal generator,

a RF power amplifying circuit,

power supplying lines, and

a precise power detector including:

a precise detecting module including: (i) an add circuit, (ii) a subtraction circuit, (iii) a rectification circuit including at least two detecting diodes and a first operational amplifier, and (iv) a filtering-amplifying circuit including a capacitor and a second operational amplifier,

a voltage mutual inductor directly connected to the precise detecting module,

a current mutual inductor directly connected to the precise detecting module, and

a microcontroller integrated with an analog-digital converter and a micro-processing unit, wherein:

the add circuit performs an addition on the signals from the voltage mutual inductor and the current mutual inductor, the subtraction circuit performs a subtraction on the signals from the voltage mutual inductor and the current mutual inductor, and

the add circuit and the subtraction circuit are respectively connected to the rectification circuit, the rectification circuit is connected to the filtering-amplifying circuit, and the filtering-amplifying circuit is connected to the microcontroller.

2. The RF power supply of claim 1 , wherein the precise detecting module further comprises:

a multi-way switch, an input terminal of which is respectively connected to an output terminal of the add circuit and an output terminal of the subtraction circuit, the multi-way switch transfers an output signal of the add circuit and an output signal of the subtraction circuit to the rectification circuit according to an instruction of the microcontroller.

3. The RF power supply of claim 1 , wherein

an anode of one of the at least two detecting diodes is connected to an inverting input terminal of the rectifying operational amplifier, and a cathode of the one of the at least two detecting diodes is connected to an output terminal of the rectifying operational amplifier, and another of the at least two detecting diodes is disposed between the output terminal of the rectifying operational amplifier and an input terminal of the filtering-amplifying circuit.

4. The RF power supply of claim 3 , wherein the voltage level of a non-inverting input terminal of the rectifying operational amplifier is less than 0.01 volt.

5. The RF power supply of claim 4 , wherein the detecting diodes are Schottky diodes with low break-over voltage.

6. The RF power supply of claim 5 , wherein the rectifying operational amplifier is a high-speed operational amplifier with a bandwidth greater than 1 GHz.

7. The RF power supply of claim 6 , wherein the filtering-amplifier circuit is a first-order filtering-amplifying circuit composed of operational amplifiers, resistors, and capacitors.

8. The RF power supply of claim 6 , wherein the filtering-amplifier circuit is a second-order filtering-amplifying circuit composed of operational amplifiers, resistors, and capacitors.

9. The RF power supply of claim 8 , wherein the resistances of an input resistor of the rectifying operational amplifier, a feedback resistor connected between the inverting input terminal and the output terminal of the rectifying operational amplifier, and a resistor of the filtering-amplifying circuit are configured according to the gain and the input range of the precise detecting module.

10. The RF power supply of claim 9 , wherein the work frequency of the RF power supply is 2 MHz, 13.56 MHz or 27.12 MHz.

11. The RF power supply of claim 2 , wherein

an anode of one of the at least two detecting diodes is connected to an inverting input terminal of the rectifying operational amplifier, and a cathode of the one of the at least two detecting diodes is connected to an output terminal of the rectifying operational amplifier, and another of the at least two detecting diodes is disposed between the output terminal of the rectifying operational amplifier and an input terminal of the filtering-amplifying circuit.

12. The RF power supply of claim 11 , wherein the voltage level of a non-inverting input terminal of the rectifying operational amplifier is less than 0.01 volt.

13. The RF power supply of claim 12 , wherein the detecting diodes are Schottky diodes with low break-over voltage.

14. The RF power supply of claim 13 , wherein the rectifying operational amplifier is a high-speed operational amplifier with a bandwidth greater than 1 GHz.

15. The RF power supply of claim 14 , wherein the filtering-amplifying circuit is a first-order filtering-amplifier circuit composed of operational amplifiers, resistors, and capacitors.

16. The RF power supply of claim 14 , wherein the filtering-amplifier circuit is a second-order filtering-amplifying circuit composed of operational amplifiers, resistors, and capacitors.

17. The RF power supply of claim 16 , wherein the resistances of an input resistor of the rectifying operational amplifier, a feedback resistor connected between the inverting input terminal and the output terminal of the rectifying operational amplifier, and a resistor of the filtering-amplifying circuit are configured according to the gain and the input range of the precise detecting module.

18. The RF power supply of claim 17 , wherein the work frequency of the RF power supply is 2 MHz, 13.56 MHz or 27.12 MHz.