A sampling device with a shielded shell for radio frequency power supply

Abstract

The present invention discloses a sampling device with a shielded shell for a radio frequency power supply, which is used for a 13.56 MHz radio frequency power supply. The device includes a printed circuit board (PCB), a filter circuit and a multiplier mounted on the front of the PCB, a metal shielding shell attached to the filter circuit and the multiplier, and a directional coupler mounted on the back of the PCB, with the coupling output of the directional coupler aligned with the filter circuit. The present invention mounts the filter circuit and the multiplier on the front of the PCB and attaches a metal shielding shell thereon, eliminating interference from external signals on the multiplier. The directional coupler is mounted on the back of the PCB, allowing the coupling output line of the directional coupler to pass directly through the PCB to the input of the filter circuit, shortening the length of the sampling signal line and reducing external interference.

Description

Technical Field

[0001] The present invention relates to the field of radio frequency power supplies, and in particular to a sampling device with a shielding shell for a radio frequency power supply. Background Art

[0002] To improve output power control accuracy in 13.56MHz RF power supplies, precise output power sampling is required. This allows the control circuit to perform more accurate calculations, minimize errors, and achieve higher output precision during closed-loop control. In a typical sampling circuit, a directional coupler is used to sample the power supply output voltage signal, which is then filtered and fed to a multiplier for calculation before being sent to the control circuit. Because high-power RF power supplies radiate RF signals into space through transmission lines during transmission, the sampling circuit and multiplier are susceptible to interference from these RF signals in open environments, resulting in reduced sampling accuracy. Summary of the Invention

[0003] The purpose of the present invention is to provide an anti-interference, high-precision sampling device for a 13.56 MHz radio frequency power supply.

[0004] To achieve the above-mentioned object, the technical solution of the present invention is: a sampling device with a shielded shell for a radio frequency power supply, used for a 13.56 MHz radio frequency power supply, comprising a PCB board, a filter circuit and a multiplier mounted on the front of the PCB board, a metal shielding shell attached to the filter circuit and the multiplier, and a directional coupler mounted on the back of the PCB board; the coupling output end of the directional coupler is aligned with the filter circuit;

[0005] The filtering circuit includes a first filtering circuit and a second filtering circuit, and the multiplier includes a first multiplier and a second multiplier;

[0006] The input end of the directional coupler is connected to an input port, and the output end of the directional coupler is connected to an output port; the first coupled output end of the directional coupler is connected to a first output line, the first output line passes through a PCB board and is connected to a first filtering circuit, the first filtering circuit is connected to a first multiplier, and the first multiplier is connected to an interface circuit; the second coupled output end of the directional coupler is connected to a second output line, the second output line passes through a PCB board and is connected to a second filtering circuit, the second filtering circuit is connected to a second multiplier, and the second multiplier is connected to the interface circuit; the interface circuit is connected to a control circuit; the input port and the output port are respectively connected to ground wires.

[0007] The beneficial effects of the present invention are:

[0008] The present invention mounts the filter circuit and multiplier on the front of a PCB and adds a metal shield to eliminate interference from external signals on the multiplier. A directional coupler is mounted on the back of the PCB, allowing the coupled output line of the directional coupler to pass directly through the PCB and be delivered to the input of the filter circuit. This shortens the length of the sampling signal line and reduces external interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a structural schematic diagram of the present invention;

[0010] Figure 2 This is the circuit topology diagram of the present invention. DETAILED DESCRIPTION

[0011] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings.

[0012] like Figure 1 A shielded sampling device for a 13.56 MHz RF power supply is shown. It includes a PCB 1, with a filter circuit and a multiplier mounted on the front. A metal shield 2 surrounds the filter circuit and multiplier, and a directional coupler 3 is mounted on the back of the PCB 1. The coupled output of the directional coupler is aligned with the filter circuit, and the coupled output line passes directly through the PCB 1 and is fed to the filter circuit input, shortening the sampling signal line and reducing external interference.

[0013] The filtering circuit includes a first filtering circuit 4 and a second filtering circuit 5 , and the multiplier includes a first multiplier 6 and a second multiplier 7 .

[0014] The input end of the directional coupler 3 is connected to the input port IN, and the output end of the directional coupler 3 is connected to the output port OUT; the first coupled output end of the directional coupler 3 is connected to the first output line 8, which passes through the PCB board and is connected to the first filter circuit 4, the first filter circuit 4 is connected to the first multiplier 6, and the first multiplier 6 is connected to the interface circuit 9; the second coupled output end of the directional coupler 3 is connected to the second output line 10, which passes through the PCB board 1 and is connected to the second filter circuit 5, the second filter circuit 5 is connected to the second multiplier 7, and the second multiplier 7 is connected to the interface circuit 11; the interface circuit 11 is connected to the control circuit (not shown in the figure); the input port IN and the output port OUT are respectively connected to the ground line GND.

[0015] There are two main types of external interference in RF power sampling devices: interference signals received on the coupled output line of the directional coupler and interference received at the signal input of the multiplier. This design mounts the filter circuit and multiplier on the front of the PCB and adds a metal shield to eliminate external interference on the multiplier. The directional coupler is mounted on the back of the PCB, allowing the coupled output line of the directional coupler to pass directly through the PCB and be delivered to the input of the filter circuit. This shortens the sampling signal line and reduces external interference.

[0016] The embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

Claims

1. A sampling device with a shielded shell for a radio frequency power supply, used for a 13.56 MHz radio frequency power supply, characterized in that: include A PCB board, wherein a filter circuit and a multiplier are mounted on the front of the PCB board, the filter circuit and the multiplier are additionally provided with a metal shielding shell, and a directional coupler is mounted on the back of the PCB board; the coupling output end of the directional coupler is aligned with the filter circuit; The filtering circuit includes a first filtering circuit and a second filtering circuit, and the multiplier includes a first multiplier and a second multiplier; The input end of the directional coupler is connected to an input port, and the output end of the directional coupler is connected to an output port; the first coupled output end of the directional coupler is connected to a first output line, the first output line directly passes through a PCB board and is connected to a first filtering circuit, the first filtering circuit is connected to a first multiplier, and the first multiplier is connected to an interface circuit; the second coupled output end of the directional coupler is connected to a second output line, the second output line directly passes through a PCB board and is connected to a second filtering circuit, the second filtering circuit is connected to a second multiplier, and the second multiplier is connected to the interface circuit; the interface circuit is connected to a control circuit; the input port and the output port are respectively connected to ground wires; the sampling device can shorten the length of the sampling signal line and eliminate interference of external signals on the multiplier.

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