Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Surge protection circuit for signal circuit

A technology for protecting circuits and signal lines, applied to emergency protection circuit devices, emergency protection circuit devices for limiting overcurrent/overvoltage, circuit devices, etc. The protection circuit responds slowly, the residual voltage peak is too large, etc., to improve the protection level, avoid signal loss, and respond quickly

Active Publication Date: 2015-03-11
SHENZHEN SUNLORD ELECTRONICS
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The present invention provides a surge protection circuit for signal lines, which solves the problems of slow response of the first-level protection circuit, excessive peak residual voltage, poor cooperation between the first-level and second-level protection circuits, and reduced protection effect in the prior art. problem, and the problem that the protection circuit causes loss to the signal transmitted by the signal line

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Surge protection circuit for signal circuit
  • Surge protection circuit for signal circuit
  • Surge protection circuit for signal circuit

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] Such as image 3 As shown, the surge protection circuit for signal lines provided by this embodiment is as follows:

[0021] A surge protection circuit for signal lines includes a primary protection circuit 1, a secondary protection circuit 2 and a resistance element 3. Among them, the primary protection circuit 1 and the secondary protection circuit 2 are connected in parallel with the protected circuit; the resistance element 3 is connected in series between the primary protection circuit 1 and the secondary protection circuit 2, which can limit the surge current in the primary protection circuit 1. Too much flows into the secondary protection circuit 2, thereby forming a well-coordinated primary and secondary protection circuit.

[0022] The above-mentioned primary protection circuit 1 includes a varistor Rv1 and a diode D. The varistor Rv1 is connected in series with the diode D, which reduces the capacitance of the primary protection circuit 1, increases the impedance, ...

Embodiment 2

[0029] Such as Figure 4 As shown, the surge protection circuit for signal lines provided by this embodiment is as follows:

[0030] Compared with the protection circuit provided in the first embodiment, the surge protection circuit for the signal line provided in this embodiment changes the diode D to a magnetic bead L.

[0031] A surge protection circuit for signal lines includes a primary protection circuit 4, a secondary protection circuit 2 and a resistance element 3. Among them, the primary protection circuit 4 and the secondary protection circuit 2 are connected in parallel with the protected circuit; the resistance element 3 is connected in series between the primary protection circuit 4 and the secondary protection circuit 2 to limit the surge current in the primary protection circuit 4 Too much flows into the secondary protection circuit 2, thereby forming a well-coordinated primary and secondary protection circuit.

[0032] The above-mentioned primary protection circuit 4...

Embodiment 3

[0039] The circuit structure of this embodiment is the same as that of embodiment 1, such as image 3 As shown, in this embodiment, the DC working voltage of the varistor Rv1 of the primary protection circuit 1 is 9V, the breakdown voltage is 14V, and the diode D uses a rectifier diode. Under the 8 / 20μs waveform and 29A impulse current, it passes through the primary The current change curve S2 and voltage change curve S2 after the discharge of the protection circuit 1 are as Figure 5 As shown, the peak value of the residual voltage after discharge is 16.56V; when the diode D in the first-level protection circuit 1 is replaced with a gas discharge tube with a DC breakdown voltage of 270V and the other parameters remain unchanged, the waveform diagram Such as figure 2 As shown, the peak residual voltage generated by it is 277.8V. It can be seen that the use of diodes and varistors in series in the primary protection circuit can effectively absorb surges, greatly reduce the resi...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a surge protection circuit for a signal circuit. The surge protection circuit for the signal circuit comprises a primary protection circuit, a secondary protection circuit and a resistor element. The primary protection circuit and the secondary protection circuit are connected in parallel with a protected circuit; the resistor element with low resistance is connected in series between the primary protection circuit and the secondary protection circuit. The primary protection circuit comprises a piezoresistor and a diode or a piezoresistor and a magnetic bead; the piezoresistor is connected in series with the diode or the magnetic bead; and the secondary protection circuit comprises a piezoresistor with low capacitance. Under a normal operation condition of a line, the primary protection circuit and the secondary protection circuit are in a high-impedance state, and thus, influence on signal transmission is small. When a surge peak is generated, a quick response is made by the primary protection circuit so as to discharge a surge in low-impedance state; surge current is further restrained by the resistor element so as to reduce the surge flowing into the secondary protection circuit; and a clamp voltage is further reduced by the piezoresistor in the secondary protection circuit, so that a protection level is improved.

Description

Technical field [0001] The invention relates to an emergency protection circuit, in particular to a surge protection circuit for signal lines. Background technique [0002] A Chinese patent application document with publication number 102025141A discloses a surge protection circuit, such as figure 1 As shown, a gas discharge tube is used in the primary protection circuit of the anti-surge protection circuit to discharge the surge, and the varistor is connected in series with the gas discharge tube to solve the freewheeling problem of the gas discharge tube, but the response speed of the gas discharge tube itself Slower, the surge current will flow into the secondary protection circuit before the primary protection circuit responds, and a larger residual voltage spike will appear, such as figure 2 As shown, the coordination of the primary and secondary protection circuits creates a gap, which greatly reduces the protection strength. Varistors have the advantages of large current ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H02H9/04
Inventor 毛海波冯志刚贾广平杜士雄
Owner SHENZHEN SUNLORD ELECTRONICS
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com