CN202679349U - Voltage amplitude limit module for antenna in radio frequency identification system - Google Patents
Voltage amplitude limit module for antenna in radio frequency identification system Download PDFInfo
- Publication number
- CN202679349U CN202679349U CN 201220316361 CN201220316361U CN202679349U CN 202679349 U CN202679349 U CN 202679349U CN 201220316361 CN201220316361 CN 201220316361 CN 201220316361 U CN201220316361 U CN 201220316361U CN 202679349 U CN202679349 U CN 202679349U
- Authority
- CN
- China
- Prior art keywords
- resistance
- effect transistor
- field effect
- channel enhancement
- enhancement field
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)
Abstract
The utility model discloses a voltage amplitude limit module for an antenna in a radio frequency identification system, comprising a first N channel enhanced field-effect tube, a second N channel enhanced field-effect tube, a first resistor, a second resistor, a third resistor, a fourth resistor and a first capacitance, wherein two ends of the first resistor are respectively connected with the drain of the first N channel enhanced field-effect tube and the second resistor; the second resistor is connected with the drain of the second N channel enhanced field-effect tube; the third resistor is in parallel with the first capacitance after being connected with the fourth resistor in series so as to form a series-parallel line; the series-parallel line is provided with connection between one end of the third resistor and the line between the first resistor and the second resistor; and the grids of the first N channel enhanced field-effect tube and the second N channel enhanced field-effect tube are connected with the line between the third resistor and the fourth resistor. The voltage amplitude limit module for an antenna in a radio frequency identification system can realize voltage amplitude limit for the antenna without any influence on the power by adjusting the first N channel enhanced field-effect tube and the second N channel enhanced field-effect tube.
Description
Technical field
The utility model relates to the radio-frequency technique field, specifically the voltage amplitude limit module of antenna in the radio-frequency recognition system.
Background technology
Radio-frequency (RF) identification is one of the most contactless Target Recognition of current application, and it has the advantages such as noncontact, read-write is flexible, speed is fast, fail safe is high, therefore is widely used in every field.Radio-frequency recognition system mainly comprises reader and electronic tag, the energy that electronic tag receives reader can be affected by the angle between operating distance and the reader antenna, the voltage that electronic tag is sensed may be larger, so must there be independent modular circuit to realize amplitude limit, with limiting voltage within limits, breakdown to prevent the receiving metal-oxide-semiconductor grid.The simplest direct measure of amplitude limit is to reduce coupling coefficient, people usually reduce coupling coefficient by the operating distance of adjusting reader and electronic tag or the input capacitance of adjusting electronic tag now, wherein, adopting the operating distance of adjusting reader and electronic tag is to be difficult to hold for operating personnel, and the method does not gear to actual circumstances; Change the input capacitance of electronic tag, namely be to change resonance frequency, reduce coupling coefficient, the power that transmits in the electronic tag also can reduce, the realization of electric capacity can take larger chip area in large scale integrated circuit design, and the parameter of electric capacity is floated relatively large.
The utility model content
The purpose of this utility model is to overcome the deficiencies in the prior art, and the control of a kind of convenient operation is provided, and is simple in structure, and can not affect the voltage amplitude limit module of antenna in the radio-frequency recognition system of delivering power on electronic tag during the aerial voltage amplitude limit.
The purpose of this utility model is achieved through the following technical solutions: the voltage amplitude limit module of antenna in the radio-frequency recognition system, comprise a N channel enhancement field effect transistor, the 2nd N channel enhancement field effect transistor, the first resistance, the second resistance, the 3rd resistance, the 4th resistance and the first electric capacity, the two ends of described the first resistance respectively with the drain electrode of a N channel enhancement field effect transistor be connected resistance and be connected, the other end that the second resistance connects the first resistance terminal relatively is connected with the drain electrode of the 2nd N channel enhancement field effect transistor, the one N channel enhancement field effect transistor source electrode and the 2nd N channel enhancement field effect transistor source grounding, consist of the connection in series-parallel circuit with the first Capacitance parallel connection after described the 3rd resistance and the series connection of the 4th resistance, this connection in series-parallel circuit is provided with an end of the 3rd resistance and the connection between the first resistance and the second resistance, its other end ground connection, the grid of a described N channel enhancement field effect transistor and the 2nd N channel enhancement field effect transistor are all and the connection between the 3rd resistance and the 4th resistance.
Be connected with the first antenna signal input part on the circuit between described the first resistance and the N channel enhancement field effect transistor drain electrode, be connected with the second antenna signal input part on the circuit between the second resistance and the drain electrode of the 2nd N channel enhancement field effect transistor.The utility model is convenient to and external antenna by the first antenna signal input part and the second antenna signal input part are set.
Described the first resistance, the second resistance and the 3rd resistance are adjustable resistance.The utility model can be by regulating and control to change limiting voltage of the present utility model to the resistance of the first resistance, the second resistance and the 3rd resistance, thereby easy to operate when making the utility model change limiting voltage.
The utility model is when using, the first resistance, the second resistance and the first electric capacity are used for the sampling radiofrequency signal, form on the 3rd resistance and the 4th resistance with reference to control voltage, the one N channel enhancement field effect transistor and the 2nd N channel enhancement field effect transistor are leak-off pipe, and a N channel enhancement field effect transistor and the 2nd N channel enhancement field effect transistor are connected in parallel on antenna ends and carry out the amplitude limit shunting.When the signal of sampling is higher than reference level, the electric current of the 4th resistance of flowing through increases, therefore the current potential of controlling a N channel enhancement field effect transistor and the 2nd N channel enhancement field effect transistor grid improves, increase the ducting capacity of a N channel enhancement field effect transistor and the 2nd N channel enhancement field effect transistor, the electric current of the N channel enhancement field effect transistor of flowing through and the 2nd N channel enhancement field effect transistor increases, reduce the pay(useful) load of label antenna, thus the voltage amplitude of restriction aerial signal.The connection in series-parallel circuit that the 3rd resistance, the 4th resistance and the first electric capacity consist of in the utility model is filter circuit, the conducting degree of this filter circuit feedback adjusting the one N channel enhancement field effect transistor and the 2nd N channel enhancement field effect transistor, thus voltage is stable when guaranteeing the utility model application.
Compared with prior art, the utlity model has following beneficial effect: the utility model comprises a N channel enhancement field effect transistor, the 2nd N channel enhancement field effect transistor, the first resistance, the second resistance, the 3rd resistance, the 4th resistance and the first electric capacity, the utility model uses the quantity of electronic component few, overall structure is simple, volume is little when being integrated on the module, be convenient to realize, cost is low, and the utility model passes through to improve the grid voltage of a N channel enhancement field effect transistor and the second enhancement mode field effect transistor when using, can not exert an influence to power, when being higher than certain voltage value, input voltage makes shunt circuit conducting in parallel, make the electric current of circuit become large, thereby make the voltage voltage stabilizing in certain scope.
Description of drawings
Fig. 1 is the structural representation of the utility model embodiment.
The corresponding name of Reference numeral is called in the accompanying drawing: N1-the one N channel enhancement field effect transistor, N2-the 2nd N channel enhancement field effect transistor, C1-first electric capacity, R1-first resistance, R2-second resistance, R3-the 3rd resistance, R4-the 4th resistance, Ant1-first antenna signal input part, Ant2-second antenna signal input part.
Embodiment
The utility model is described in further detail below in conjunction with embodiment and accompanying drawing, but execution mode of the present utility model is not limited to this.
Embodiment:
As shown in Figure 1, the voltage amplitude limit module of antenna in the radio-frequency recognition system, comprise shell and setting internal circuit in the enclosure, internal circuit comprises a N channel enhancement field effect transistor N1, the 2nd N channel enhancement field effect transistor N2, the first resistance R 1, the second resistance R 2, the 3rd resistance R 3, the 4th resistance R 4 and the first capacitor C 1, wherein, for the ease of voltage is regulated and control, the first resistance R 1, the second resistance R 2 and the 3rd resistance R 3 are adjustable resistance.The two ends of the first resistance R 1 respectively with the drain electrode of a N channel enhancement field effect transistor N1 be connected resistance R 2 and be connected, the other end that the second resistance R 2 connects the first resistance R 1 end relatively is connected a N channel enhancement field effect transistor N1 source electrode and the 2nd N channel enhancement field effect transistor N2 source grounding with the drain electrode of the 2nd N channel enhancement field effect transistor N2.With the first capacitor C 1 formation connection in series-parallel circuit in parallel, this connection in series-parallel circuit is provided with an end of the 3rd resistance R 3 and the connection between the first resistance R 1 and the second resistance R 2, its other end ground connection after the 3rd resistance R 3 and 4 series connection of the 4th resistance R.The grid of the one N channel enhancement field effect transistor N1 and the 2nd N channel enhancement field effect transistor N2 all and the connection between the 3rd resistance R 3 and the 4th resistance R 4.
Be connected with the first antenna signal input part Ant1 on the circuit between the first resistance R 1 and the N channel enhancement field effect transistor N1 drain electrode, be connected with the second antenna signal input part Ant2 on the circuit between the second resistance R 2 and the 2nd N channel enhancement field effect transistor N2 drain electrode, the first antenna signal input part Ant1 and the second antenna signal input part Ant2 are connected on the antenna when using.
As mentioned above, then can well realize the utility model.
Claims (3)
1. the voltage amplitude limit module of antenna in the radio-frequency recognition system, it is characterized in that: comprise a N channel enhancement field effect transistor (N1), the 2nd N channel enhancement field effect transistor (N2), the first resistance (R1), the second resistance (R2), the 3rd resistance (R3), the 4th resistance (R4) and the first electric capacity (C1), the two ends of described the first resistance (R1) respectively with the drain electrode of a N channel enhancement field effect transistor (N1) be connected resistance (R2) and be connected, the other end that the second resistance (R2) connects the first resistance (R1) end relatively is connected with the drain electrode of the 2nd N channel enhancement field effect transistor (N2), the one N channel enhancement field effect transistor (N1) source electrode and the 2nd N channel enhancement field effect transistor (N2) source grounding, after the series connection of described the 3rd resistance (R3) and the 4th resistance (R4) with the first electric capacity (C1) formation in parallel connection in series-parallel circuit, this connection in series-parallel circuit is provided with an end of the 3rd resistance (R3) and the connection between the first resistance (R1) and the second resistance (R2), its other end ground connection, a described N channel enhancement field effect transistor (N1) and the 2nd both grids of N channel enhancement field effect transistor (N2) are all and the connection between the 3rd resistance (R3) and the 4th resistance (R4).
2. the voltage amplitude limit module of antenna in the radio-frequency recognition system according to claim 1, it is characterized in that: be connected with the first antenna signal input part (Ant1) on the circuit between described the first resistance (R1) and a N channel enhancement field effect transistor (N1) drain electrode, be connected with the second antenna signal input part (Ant2) on the circuit between the second resistance (R2) and the drain electrode of the 2nd N channel enhancement field effect transistor (N2).
3. the voltage amplitude limit module of antenna in the radio-frequency recognition system according to claim 1 and 2, it is characterized in that: described the first resistance (R1), the second resistance (R2) and the 3rd resistance (R3) are adjustable resistance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220316361 CN202679349U (en) | 2012-07-03 | 2012-07-03 | Voltage amplitude limit module for antenna in radio frequency identification system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220316361 CN202679349U (en) | 2012-07-03 | 2012-07-03 | Voltage amplitude limit module for antenna in radio frequency identification system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202679349U true CN202679349U (en) | 2013-01-16 |
Family
ID=47500221
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220316361 Expired - Fee Related CN202679349U (en) | 2012-07-03 | 2012-07-03 | Voltage amplitude limit module for antenna in radio frequency identification system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202679349U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103532578A (en) * | 2012-07-03 | 2014-01-22 | 成都市宏山科技有限公司 | Voltage amplitude-limiting module of antenna in radio frequency identification system |
-
2012
- 2012-07-03 CN CN 201220316361 patent/CN202679349U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103532578A (en) * | 2012-07-03 | 2014-01-22 | 成都市宏山科技有限公司 | Voltage amplitude-limiting module of antenna in radio frequency identification system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104518654B (en) | High-voltage starting circuit | |
| CN102200791A (en) | Low dropout linear regulator structure | |
| CN202679349U (en) | Voltage amplitude limit module for antenna in radio frequency identification system | |
| CN202677442U (en) | Voltage amplitude limiting module for antenna in electronic tag | |
| CN202677431U (en) | Amplitude limit circuit of antenna in electronic tag | |
| CN202663107U (en) | Voltage amplitude limiting system of antenna signal in radio frequency identification | |
| CN202632345U (en) | Antenna amplitude-limit circuit for electronic tags in radio frequency system | |
| CN203747781U (en) | Switching circuit between the inner and outer parts of antenna | |
| CN202632348U (en) | Antenna limiter of electronic tag of radio frequency identification system | |
| CN103530677A (en) | Antenna amplitude limiting circuit of electronic tag in radio frequency system | |
| CN101801152A (en) | Method for realizing electrostatic prevention at radio-frequency port | |
| CN103532578A (en) | Voltage amplitude-limiting module of antenna in radio frequency identification system | |
| CN103532119A (en) | Voltage amplitude-limiting system of antenna signal in electronic tag | |
| CN103595113A (en) | Intelligent charger with wireless charging | |
| CN103530678A (en) | Antenna limiter of electronic tag in radio frequency identification system | |
| CN203011996U (en) | Limit peak value current detection circuit of switch power supply | |
| CN103293383A (en) | Test circuit for series resistance in MOSFET (metal oxide semiconductor field-effect transistor) power devices | |
| CN103530670A (en) | Amplitude limiting circuit of antenna in electronic tag | |
| CN202677432U (en) | System for modulating load voltage in electronic tag | |
| CN202632147U (en) | Voltage stabilizer for stabilizing voltage in electronic label | |
| CN104569558B (en) | Peak detector for amplifier | |
| CN203689529U (en) | Wireless radio frequency card reader | |
| CN103530676A (en) | Voltage amplitude-limiting module applied to antenna of electronic tag | |
| CN108206591B (en) | Magnetic resonance receiving system and magnetic resonance receiving terminal thereof | |
| CN103532406A (en) | Rectifier applied to electronic tag |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130116 Termination date: 20130703 |