CN113346721A - Filter for high-frequency suppression by using ferrite magnetic material - Google Patents

Filter for high-frequency suppression by using ferrite magnetic material Download PDF

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Publication number
CN113346721A
CN113346721A CN202110455900.5A CN202110455900A CN113346721A CN 113346721 A CN113346721 A CN 113346721A CN 202110455900 A CN202110455900 A CN 202110455900A CN 113346721 A CN113346721 A CN 113346721A
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China
Prior art keywords
terminal
resistor
filter
esd
magnetic material
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CN202110455900.5A
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Chinese (zh)
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吴文明
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Shenzhen B Tron Electronic & Technology Co ltd
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Shenzhen B Tron Electronic & Technology Co ltd
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Priority to CN202110455900.5A priority Critical patent/CN113346721A/en
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00Details of apparatus for conversion
    • H02M1/12Arrangements for reducing harmonics from ac input or output
    • H02M1/126Arrangements for reducing harmonics from ac input or output using passive filters
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02MAPPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00Details of apparatus for conversion
    • H02M1/44Circuits or arrangements for compensating for electromagnetic interference in converters or inverters
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)

Abstract

The invention provides a filter for high-frequency suppression by using a ferrite magnetic material, which comprises: zero line and live wire, zero line and live wire are connected with the both sides of switch respectively, the live wire is connected with first terminal, and first terminal is connected with first switch through first resistance ESR and first variable resistance ESL, and first terminal is connected with the second terminal, the second terminal is connected with the second switch through second resistance ESR and second variable resistance ESL, and the second terminal is connected with the third terminal, and the third terminal is connected with diode and ESD suppressor, and the ESD suppressor includes positive ESD protection module and negative direction ESD protection module. In the invention, the common-film filter part and the ESD suppressor are connected and combined into a whole, so that the number of components and the occupied area are reduced, the common-film filter has high-frequency suppression protection performance on common-mode noise, and simultaneously has an electrostatic suppression function to prevent electrostatic discharge from damaging important elements.

Description

Filter for high-frequency suppression by using ferrite magnetic material
Technical Field
The invention relates to the technical field of filters for high-frequency suppression by using ferrite magnetic materials, in particular to a filter for high-frequency suppression by using ferrite magnetic materials.
Background
The common mode filter adopts double-wire parallel winding of a ferrite magnetic core, suppresses an interference source by a low differential mode noise signal, is difficult to deform in a high-speed signal, has good noise suppression countermeasures, has high common mode noise suppression and low differential mode noise signal suppression, is relatively simple in design and comprises a common mode capacitor, a balun or a common mode inductor, the common mode capacitor bypasses the common mode current of two input wires to the ground, the common mode inductor presents a balanced impedance, namely the impedances in a power wire and a ground wire are equal, the impedance presents impedance characteristics to the common mode noise, and the common mode filter has good application in aspects of suppressing EMI noise of electronic equipment, DVC, an IEEE1394 line of STB (electronic equipment), a liquid crystal display panel, a low-voltage differential signal, a USB (universal serial bus) line of a personal computer and peripheral equipment and the like.
In the process of implementing the embodiment, the inventor finds that at least the following defects exist in the prior art:
(1) the existing common mode filter and the static suppressor are two separated independent components, the number of components is large, the installation area is large, and the existing common mode filter is easy to be influenced by static electricity because the components are smaller and smaller, and lacks the performance of high-frequency suppression and protection.
(2) The existing common mode filter is very widely used, but the effect is poor in the aspect of magnetic permeability, the initial magnetic permeability is low, the integral magnetic induction intensity is low, the integral effect is poor, the using effect is poor, the time for high common mode noise suppression and low differential mode noise signal suppression is long, and the common mode filter is not convenient for a user to use;
(3) the ESD circuit has a large on-current when the gate and the source of the P-type GAN enhancement power device 30 have reverse voltage biases, which results in the ESD circuit being incompatible with a gate negative voltage test for detecting gate related defects, thereby making it difficult for the device to simultaneously consider reliability and ESD tolerance.
Disclosure of Invention
The present invention is directed to a filter for high frequency suppression using a ferrite magnetic material, so as to solve the above-mentioned problems of the related art.
The technical scheme of the invention is as follows: a filter for high frequency rejection using ferrite magnetic material, comprising: zero line and live wire, zero line and live wire are connected with the both sides of switch respectively, the live wire is connected with first terminal, and first terminal is connected with first switch through first resistance ESR and first variable resistance ESL, and first terminal is connected with the second terminal, the second terminal is connected with the second switch through second resistance ESR and second variable resistance ESL, and the second terminal is connected with the third terminal, and the third terminal is connected with diode and ESD suppressor, and the ESD suppressor includes positive ESD protection module and negative-going ESD protection module, and one side of ESD suppressor is connected with P type GaN enhancement mode power device, the zero line is connected with the condenser, and the inside of condenser is connected with resistor R and variable resistor L respectively.
As a further optimization of the technical solution, the third terminal is connected to a ground line, and the third terminal is connected to a second switch.
As a further optimization of the technical scheme, a fourth terminal is arranged between the ground wire and the live wire, and the fourth terminal is connected with a third switch.
As a further optimization of the technical scheme, an alternating current contactor is connected between the grounding wire and the zero line.
As a further optimization of the present technical solution, the forward ESD protection module includes a clamp diode string, a resistor 01 is connected to one end of the clamp diode string, an effect tube 02 is connected between the clamp diode string and the resistor 01, the effect tube 01 is connected to one end of the effect tube 02, and one end of the effect tube 02 is connected to one end of the resistor 01.
As a further optimization of the technical solution, the negative ESD protection module includes a resistor 02, one end of the resistor 02 is connected to a charging capacitor, the other end of the resistor 02 is connected to an effect tube 03, and one end of the effect tube 03 is connected to an effect tube 04.
As a further optimization of this technical scheme, first terminal is connected with the USB controller through variable resistance RT1, the third terminal is connected with the USB interface, be connected with paster ferrite bead between USB controller and the USB interface, and the one end of paster ferrite bead is connected with thermistor U, the one end of USB controller is connected with resistance through variable resistance RT2, and the other end of resistance is connected with the USB interface, the one end of variable resistance RT1 is connected with fixed capacitor CT, and fixed capacitor CT's the other end and variable resistance RT 2's one end are connected, and the one end of resistance is connected with the ESD inhibitor.
As a further optimization of the technical scheme, one end of the USB interface is connected to a common terminal, and one ends of the fixed capacitor CT, the ESD suppressor, the thermistor and the common terminal are all connected to a ground wire.
The invention provides a filter for high-frequency suppression by using ferrite magnetic materials through improvement, compared with the prior art, the filter has the following improvement and advantages:
first, in the invention, the zero line, the live wire, the first terminal, the first resistor ESR, the first variable resistor ESL, the first switch, the second terminal, the second resistor ESR, the second variable resistor ESL, the second switch, the third terminal, the diode and the capacitor form a common-film filter part, and the common-film filter part is connected and combined with the ESD suppressor into a whole, thereby not only reducing the number of components and parts and reducing the occupied area, but also having high-frequency suppression and protection performance on common-mode noise, and simultaneously having an electrostatic suppression function to prevent electrostatic discharge from damaging important components.
When the common mode filter is used, the first resistor ESR, the second resistor ESR, the first variable resistor ES and the second variable resistor ES are matched with each other, the overall magnetic permeability can be improved, the capacitor and the diode are matched with each other, the magnetic induction intensity can be further ensured, the common mode filter has a good effect in high common mode noise suppression and low differential mode noise signal suppression, and the suppression time is shortened.
Thirdly, in the present invention, when the P-type GaN enhancement mode power device on one side of the ESD suppressor experiences a negative ESD event, the negative ESD event can generate a transient change negative voltage with short pulse width and high change slope, the transient change negative voltage can generate a shift current, the generated shift current charges the charging capacitor, further, a voltage is generated on the resistor 01, the voltage on the resistor 01 enables the effect tube 03 to be conducted, at the moment, the paths of the effect tube 03 and the effect tube 04 are conducted, negative ESD energy is released, and no voltage drop exists under the steady-state condition of the resistor 01, therefore, under the negative steady-state leakage test condition of the grid electrode of the P-type GaN enhancement type power device, the effect tube 01 is turned off, therefore, large leakage current cannot be generated in the negative direction, and the negative ESD protection module is compatible with the negative leakage test of the grid electrode of the P-type GaN enhanced power device, so that the device can simultaneously give consideration to the reliability and the ESD tolerance.
Drawings
The invention is further explained below with reference to the figures and examples:
FIG. 1 is an electrical schematic of a portion of a common mode filter of the present invention;
FIG. 2 is an electrical schematic of the common mode filter portion of the present invention in its operating state;
FIG. 3 is a circuit diagram of an ESD suppressor in accordance with the present invention;
fig. 4 is a circuit diagram of a combined structure of an ESD suppressor and a common mode filter according to the present invention.
Detailed Description
The present invention will be described in detail with reference to fig. 1 to 4, and the technical solutions in the embodiments of the present invention will be clearly and completely described, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The present invention provides a filter for high frequency suppression using a ferrite magnetic material by improvement, as shown in fig. 1 to 4, a filter for high frequency suppression using a ferrite magnetic material, comprising: zero line and live wire, zero line and live wire are connected with the both sides of switch respectively, the live wire is connected with first terminal, first terminal is connected with first switch through first resistance ESR and first variable resistance ESL, and first terminal is connected with the second terminal, the second terminal is connected with the second switch through second resistance ESR and second variable resistance ESL, and the second terminal is connected with the third terminal, the third terminal is connected with diode and ESD suppressor, the ESD suppressor includes positive ESD protection module and negative-going ESD protection module, and one side of ESD suppressor is connected with P type GaN enhancement mode power device, the zero line is connected with the condenser, the inside of condenser is connected with resistor R and variable resistor L respectively.
Zero line, live wire, first terminal, first resistance ESR, first variable resistance ESL, first switch, second terminal, second resistance ESR, second variable resistance ESL, second switch, third terminal, diode and condenser constitute altogether membrane filter part, this altogether membrane filter part is connected with the ESD inhibitor and is combined as an organic whole, not only reducible components and parts quantity reduces area, and has high frequency suppression barrier propterty to common mode noise, and have the static suppression function simultaneously moreover, prevent the injury of electrostatic discharge to important component.
The third terminal is connected with a grounding wire and a second switch; the ground line can prevent electric leakage.
A fourth terminal is arranged between the grounding wire and the live wire and is connected with a third switch; the third switch can independently control the on-off of the fourth terminal.
An alternating current contactor is connected between the grounding wire and the zero line; the ac contactor is used as an actuator for connecting and disconnecting a line or frequently controlling the operation of an instrument or equipment.
The forward ESD protection module comprises a clamp diode string, one end of the clamp diode string is connected with a resistor 01, an effect tube 02 is connected between the clamp diode string and the resistor 01, one end of the effect tube 02 is connected with the effect tube 01, and one end of the effect tube 02 is connected with one end of the resistor 01.
The negative ESD protection module comprises a resistor 02, one end of the resistor 02 is connected with a charging capacitor, the other end of the resistor 02 is connected with an effect tube 03, and one end of the effect tube 03 is connected with an effect tube 04; when a negative steady-state voltage is applied to the grid electrode of the P-type GAN enhanced power device relative to the source electrode, no displacement current exists, so that no voltage drop exists at two ends of the resistor 01, the effect tube 01 is in a turn-off state, and the negative ESD protection circuit unit can be compatible with a negative voltage test in a steady state due to small leakage between the grid electrode and the source electrode.
The first terminal is connected with a USB controller through a variable resistor RT1, the third terminal is connected with a USB interface, a patch ferrite bead is connected between the USB controller and the USB interface, one end of the patch ferrite bead is connected with a thermistor U, one end of the USB controller is connected with a resistor through a variable resistor RT2, the other end of the resistor is connected with the USB interface, one end of a variable resistor RT1 is connected with a fixed capacitor CT, the other end of the fixed capacitor CT is connected with one end of a variable resistor RT2, and one end of the resistor is connected with an ESD suppressor; when the magnetic induction type high-frequency-ratio low-frequency-difference-mode noise suppression circuit is used, the magnetic permeability of the whole body can be improved under the mutual matching use of the first resistor ESR, the second resistor ESR, the first variable resistor ES and the second variable resistor ES, the mutual matching of the capacitor and the diode can guarantee the magnetic induction intensity in one step, a good effect is achieved when high common-mode noise suppression and low differential-mode noise signal suppression are achieved, and the suppression time is shortened.
One end of the USB interface is connected with a common end, and one ends of the fixed capacitor CT, the ESD suppressor, the thermistor and the common end are connected with a grounding wire; the ground line can prevent electric leakage.
The working principle or the using method of the invention is as follows: when the common mode filter is used, the magnetic permeability of the whole common mode filter can be improved under the condition that the first resistor ESR, the second resistor ESR, the first variable resistor ES and the second variable resistor ES are matched with each other, the mutual matching of the capacitor and the diode can ensure the magnetic induction intensity in one step, the common mode filter has a good effect in high common mode noise suppression and low differential mode noise signal suppression, and the suppression time is shortened;
when in use, when the P-type GaN enhancement type power device at one side of the ESD suppressor experiences a negative ESD event, the negative ESD event can generate a transient change negative voltage with short pulse width and high change slope, the transient change negative voltage can generate a shift current, and the generated shift current charges a charging capacitor, further, a voltage is generated on the resistor 01, the voltage on the resistor 01 enables the effect tube 03 to be conducted, at the moment, the paths of the effect tube 03 and the effect tube 04 are conducted, negative ESD energy is released, and no voltage drop exists under the steady-state condition of the resistor 01, therefore, under the negative steady-state leakage test condition of the grid electrode of the P-type GaN enhancement type power device, the effect tube 01 is turned off, therefore, large leakage current cannot occur in the negative direction, and the negative ESD protection module is compatible with the negative leakage test of the grid electrode of the P-type GaN enhanced power device, so that the device can simultaneously give consideration to the reliability and the ESD tolerance;
the common-film filter part is connected and combined with the ESD suppressor into a whole, so that the number of components can be reduced, the occupied area is reduced, the common-film filter has high-frequency suppression protection performance on common-mode noise, and meanwhile, the common-film filter part has an electrostatic suppression function and prevents electrostatic discharge from damaging important elements.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (8)

1. A filter for high frequency rejection using ferrite magnetic material, comprising: zero line and live wire, zero line and live wire are connected with the both sides of switch respectively, its characterized in that, the live wire is connected with first terminal, and first terminal is connected with first switch through first resistance ESR and first variable resistance ESL, and first terminal is connected with the second terminal, the second terminal is connected with the second switch through second resistance ESR and second variable resistance ESL, and the second terminal is connected with the third terminal, and the third terminal is connected with diode and ESD suppressor, and the ESD suppressor includes positive ESD protection module and negative direction ESD protection module, and one side of ESD suppressor is connected with P type GaN enhancement mode power device, the zero line is connected with the condenser, and the inside of condenser is connected with resistor R and variable resistor L respectively.
2. A filter for high frequency rejection using ferrite magnetic material as claimed in claim 1, wherein: the third terminal is connected with a grounding wire, and the third terminal is connected with a second switch.
3. A filter for high frequency rejection using ferrite magnetic material as claimed in claim 2, wherein: and a fourth terminal is arranged between the grounding wire and the live wire and is connected with a third switch.
4. A filter for high frequency rejection using ferrite magnetic material as claimed in claim 2, wherein: and an alternating current contactor is connected between the grounding wire and the zero line.
5. A filter for high frequency rejection using ferrite magnetic material as claimed in claim 1, wherein: the forward ESD protection module comprises a clamp diode string, one end of the clamp diode string is connected with a resistor 01, an effect tube 02 is connected between the clamp diode string and the resistor 01, one end of the effect tube 02 is connected with the effect tube 01, and one end of the effect tube 02 is connected with one end of the resistor 01.
6. A filter for high frequency rejection using ferrite magnetic material as claimed in claim 1, wherein: the negative ESD protection module comprises a resistor 02, one end of the resistor 02 is connected with a charging capacitor, the other end of the resistor 02 is connected with an effect tube 03, and one end of the effect tube 03 is connected with an effect tube 04.
7. A filter for high frequency rejection using ferrite magnetic material as claimed in claim 1, wherein: the first terminal is connected with the USB controller through variable resistance RT1, the third terminal is connected with the USB interface, be connected with paster ferrite bead between USB controller and the USB interface, and the one end of paster ferrite bead is connected with thermistor U, the one end of USB controller is connected with resistance through variable resistance RT2, and the other end of resistance is connected with the USB interface, the one end of variable resistance RT1 is connected with fixed capacitor CT, and fixed capacitor CT's the other end and variable resistance RT 2's one end are connected, and the one end of resistance is connected with the ESD inhibitor.
8. A filter for high frequency rejection using ferrite magnetic material as claimed in claim 7 wherein: one end of the USB interface is connected with a common terminal, and one ends of the fixed capacitor CT, the ESD suppressor, the thermistor and the common terminal are connected with a grounding wire.
CN202110455900.5A 2021-04-26 2021-04-26 Filter for high-frequency suppression by using ferrite magnetic material Pending CN113346721A (en)

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CN202110455900.5A CN113346721A (en) 2021-04-26 2021-04-26 Filter for high-frequency suppression by using ferrite magnetic material

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Application Number Priority Date Filing Date Title
CN202110455900.5A CN113346721A (en) 2021-04-26 2021-04-26 Filter for high-frequency suppression by using ferrite magnetic material

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140198418A1 (en) * 2013-01-15 2014-07-17 Citruscom Corporation Integrated circuit common-mode filters with esd protection and manufacturing method
US20140211348A1 (en) * 2013-01-29 2014-07-31 Citruscom Corporation Ic emi filter with esd protection incorporating lc resonance tanks for rejection enhancement
US20150002968A1 (en) * 2013-01-15 2015-01-01 Silergy Semiconductor Technology (Hangzhou) Ltd Integrated emi filter circuit with esd protection and incorporating capacitors
CN205230033U (en) * 2015-12-24 2016-05-11 中国长城计算机深圳股份有限公司 ESD protection device of USB interface
CN205595780U (en) * 2016-01-11 2016-09-21 深圳市三诺数字科技有限公司 Electrostatic protection device of USB interface
CN109193601A (en) * 2018-09-25 2019-01-11 华为技术有限公司 A kind of esd protection circuit

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140198418A1 (en) * 2013-01-15 2014-07-17 Citruscom Corporation Integrated circuit common-mode filters with esd protection and manufacturing method
US20150002968A1 (en) * 2013-01-15 2015-01-01 Silergy Semiconductor Technology (Hangzhou) Ltd Integrated emi filter circuit with esd protection and incorporating capacitors
US20140211348A1 (en) * 2013-01-29 2014-07-31 Citruscom Corporation Ic emi filter with esd protection incorporating lc resonance tanks for rejection enhancement
CN205230033U (en) * 2015-12-24 2016-05-11 中国长城计算机深圳股份有限公司 ESD protection device of USB interface
CN205595780U (en) * 2016-01-11 2016-09-21 深圳市三诺数字科技有限公司 Electrostatic protection device of USB interface
CN109193601A (en) * 2018-09-25 2019-01-11 华为技术有限公司 A kind of esd protection circuit

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Application publication date: 20210903

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