CN109802654A - A kind of high AC impedance circuit and its application system - Google Patents
A kind of high AC impedance circuit and its application system Download PDFInfo
- Publication number
- CN109802654A CN109802654A CN201910117736.XA CN201910117736A CN109802654A CN 109802654 A CN109802654 A CN 109802654A CN 201910117736 A CN201910117736 A CN 201910117736A CN 109802654 A CN109802654 A CN 109802654A
- Authority
- CN
- China
- Prior art keywords
- circuit
- resistance
- terminal
- base stage
- impedance circuit
- 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.)
- Pending
Links
- 239000003990 capacitor Substances 0.000 claims description 12
- 230000005611 electricity Effects 0.000 claims description 7
- 239000004065 semiconductor Substances 0.000 claims description 7
- 238000000034 method Methods 0.000 abstract description 6
- 230000007812 deficiency Effects 0.000 abstract description 4
- 230000001939 inductive effect Effects 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 11
- 230000003321 amplification Effects 0.000 description 9
- 238000003199 nucleic acid amplification method Methods 0.000 description 9
- 230000005284 excitation Effects 0.000 description 7
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 5
- 229910052710 silicon Inorganic materials 0.000 description 5
- 239000010703 silicon Substances 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 4
- 230000002238 attenuated effect Effects 0.000 description 3
- 230000015556 catabolic process Effects 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- 230000006870 function Effects 0.000 description 2
- 230000008054 signal transmission Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 230000003685 thermal hair damage Effects 0.000 description 1
Landscapes
- Amplifiers (AREA)
Abstract
The embodiment of the invention discloses a kind of high AC impedance circuit and its application systems, the high AC impedance circuit is placed between DC terminal and exchange end, the high AC impedance circuit is placed between DC terminal and exchange end, the high AC impedance circuit includes the first triode Q1, and the DC terminal is based on Q1 input dc power to exchanging end；It is in series with base resistance in DC terminal and the base stage of the Q1, is provided with AC signal feedback circuit in the base stage of exchange end and the Q1.Deficiency present in existing inductive circuit can be replaced using the device of smaller cost in embodiments of the present invention, the method that tradition realizes high AC impedance circuit with big inductance can be improved by large current characteristic in magnification region by triode.
Description
Technical field
The present invention relates to electronic circuit technology field more particularly to a kind of high AC impedance circuit and its application systems.
Background technique
Existing elevator intercom system realizes the power supply of intercommunication terminal using two-wire system bus, and uses bus transfer simultaneously
Voice signal, and this bus is also usually applied to various circuit structures using lower realization direct current supply and transmission of speech signals
In.Using its needs of the elevator intercom system of two-wire system in face of how to pass through bus to the power supply of each intercommunication terminal simultaneously simultaneously with same
The problem of to bus transfer voice signal, entire bus-type system need a kind of DC impedance smaller and the biggish device of AC impedance
Part or circuit, be placed in DC terminal end with exchange between end.
Existing realization direct current supply exchanges end high resistant using big inductance value inductance L0 under AC signal transmission mode to realize
Anti-, as shown in fig. 1, the left side inductance L0 is DC terminal to entire equivalent schematic diagram, i.e. DC terminal supplies power for, and the right is exchange
End, the i.e. high frequency ac signals such as voice can be transmitted at exchange end, and inductance L0 can indicate the impedance of AC signal are as follows:
Z0=R0+jωL0；Wherein R0For the resistance of inductance, L0For inductance value.In the certain situation of AC signal angular frequency, inductance value
Bigger, inductance is bigger to the impedance of AC signal, smaller to the decaying of the signal at exchange end.
Here exchange end high impedance function is realized, using big inductance value inductance in order to ensure DC voltage passes through after inductance
Pressure drop is small as far as possible, therefore the resistance of inductance must be made low as far as possible, to need to use thicker conducting wire coiling inductance, this allows for electricity
It is excessive to feel volume, increased costs.Moreover, DC voltage is dynamic by the pressure drop after inductance, therefore is exported when curent change
Voltage be also dynamic, be the requirement for being extremely difficult to voltage range in the demanding occasion of some voltage ranges.
Summary of the invention
It is an object of the invention to overcome the deficiencies in the prior art, the present invention provides a kind of high AC impedance circuit and its
Application system can replace deficiency present in existing inductive circuit using the device of smaller cost, pass through triode
The method that tradition realizes high exchange end high impedance with big inductance can be improved by large current characteristic in magnification region.
To solve the above-mentioned problems, the invention proposes a kind of high AC impedance circuit, the high AC impedance circuit is set
Between DC terminal and exchange end, the high AC impedance circuit includes the first triode Q1, and the DC terminal is inputted based on Q1
Direct current is to exchanging end；It is in series with base resistance in DC terminal and the base stage of the Q1, the base stage at exchange end and the Q1
On be provided with AC signal feedback circuit.
The AC signal feedback circuit includes feedback network circuit and discharge loop, the feedback network circuit and described
Discharge loop forms the base stage that parallel circuit one end is connected to the Q1, and the other end is connected to exchange end.
The base resistance includes that resistance R4 and resistance R5, the R4 and the R5 are cascaded, and the R4 is connected to
DC terminal, the R5 are connected to the base stage of Q1.
The feedback network circuit includes capacitor C1 and resistance R7, and the discharge loop includes resistance R8；The R8 is institute
It states C1 and discharge loop is provided.
The Q1 is NPN type single-stage or multilevel semiconductor triode or is three pole of positive-negative-positive single-stage or multilevel semiconductor
Pipe.
The high AC impedance circuit further includes current-limiting circuit, and the current-limiting circuit includes the second triode Q2 and resistance
R6, the Q2 are NPN type transistor, in which:
The emitter of the base stage of the Q2 and the Q1 are connected to R6；
The collector of the Q2 is connected to the base stage of the Q1；
The emitter of the Q2 is connected to exchange end；
The collector and emitter of the Q2 and the feedback network circuit and discharge loop are formed together parallel circuit one
End is connected to the base stage of the Q1, and the other end is connected to exchange end.
The high AC impedance circuit further includes diode D1 and third transistor Q3, the Q3 are NPN type triode,
In:
The cathode of the D1 is connected to exchange end, and the anode of the D1 is connected to the emitter of Q3；
The base stage of the Q3 is connected to DC terminal, and the collector of the Q3 is connected on the circuit between the R4 and R5.
It include resistance R1, resistance R2, resistance R3 and capacitor C2 between the base stage and DC terminal of the Q3, in which:
The one end resistance R1 is connected to DC terminal, and the R1 other end is connected in parallel to the R2 and R3；
Described one end R2 is connected to R1, the R2 other end and the C2 earth；
Described one end R3 and R2 are connected in parallel R1, and the R3 other end and the C2 are connected in parallel the ground level of Q3；
Described one end C2 and the R2 earth, the C2 and the R3 are connected in parallel the base stage of Q3.
Correspondingly, the invention also provides a kind of elevator intercom system, the elevator intercom system be based on bus with it is each right
It says that terminal is powered, and is set between the DC terminal and exchange end of bus supply using with a pair of of bus transfer voice signal simultaneously
It is equipped with above-described AC impedance circuit.
Correspondingly, the system is based on same route and realizes direct current supply to load the invention also provides a kind of system
End, and signal is transmitted to load end based on exchange end, above-described AC impedance is provided between DC terminal and exchange end
Circuit.
In embodiments of the present invention, AC signal can be exported from the electric current of triode using AC signal feedback circuit
End feeds back to base stage, by triode amplification, original AC signal is maintained by network degradation, not can be equivalent to one
AC impedance is infinitely great network, therefore, can substitute traditional high inductance value inductance, so reduce the volume of product at
This, and the DC voltage of output end is in controlled range, can satisfy some pairs of voltage change ranges and has certain requirements field
It closes.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this
Some embodiments of invention for those of ordinary skill in the art without creative efforts, can be with
Other attached drawings are obtained according to these attached drawings.
Fig. 1 is to realize friendship under direct current supply in the prior art and AC signal transmission mode using big inductance value inductance L0
Flow end end high impedance circuit schematic diagram；
Fig. 2 is the high AC impedance circuit theory schematic diagram based on NPN type triode in the embodiment of the present invention；
Fig. 3 is the AC impedance circuit theory signal based on NPN type triode with overcurrent protection in the embodiment of the present invention
Figure；
Fig. 4 is the high AC impedance circuit theory schematic diagram based on PNP type triode in the embodiment of the present invention.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
High AC impedance circuit according to the present invention is placed between DC terminal and exchange end, the AC impedance electricity
Road can realize that DC terminal exchanges end with realization to load end power supply and transmits signal to load end, which is placed in directly
It flows between end and exchange end, the high AC impedance circuit includes the first triode Q1, and the DC terminal is based on Q1 input direct-current
Electricity extremely exchange end；It is in series with base resistance in DC terminal and the base stage of the Q1, is set in the base stage of exchange end and the Q1
It is equipped with AC signal feedback circuit.
It should be noted that the Q1 can be NPN type single-stage or multilevel semiconductor triode or positive-negative-positive single-stage or more
Level semiconductor triode.Transistor type in the present invention can be bipolar transistor (BJT), bipolar transistor point
Emitter (Emitter), base stage (Base) and collector (Collector) are not formed with p-type by N-type.Fig. 2 shows be based on
The high AC impedance circuit theory schematic diagram and Fig. 3 of NPN type triode are shown based on NPN type triode band overcurrent protection
AC impedance circuit theory schematic diagram specifically can be refering to Fig. 2 to Fig. 3 based on high the realized process of AC impedance circuit
Shown content.The AC impedance circuit includes: direct-flow input end Vin, DC output end Vout, load end RL, resistance R1, resistance
R2, resistance R3, resistance R4, resistance R5, resistance R6, resistance R7, resistance R8, diode D1, first capacitor C1, the second capacitor C2,
First triode Q1, the second triode Q2 and third transistor Q3 etc..
It should be noted that high AC impedance circuit here is powered to load end for realizing DC terminal and is exchanged with realization
It holds to load end and transmits signal, the collector of the Q1 is connected to DC terminal, and the emitter of Q1 is connected to resistance R6, the connection of the one end R6
The emitter output end of Q1, the R6 other end be connected to exchange end；It is in series with base resistance on the ground level of DC terminal and Q1,
It is provided with feedback network circuit and discharge loop in the base stage of exchange end and Q1, the feedback network circuit and discharge loop composition one
A AC signal feedback circuit；The feedback network circuit and discharge loop form the base stage that parallel circuit one end is connected to Q1, separately
One end is connected to exchange end.
The base resistance includes resistance R4 and resistance R5, and the R4 and R5 are cascaded, which is connected to DC terminal, the R5
It is connected to the base stage of Q1.
The feedback network circuit includes capacitor C1 and resistance R7, which includes R8；The R8 provides for C1 to discharge back
Road.
The base stage of Q2 on the AC impedance circuit and the emitter of the Q1 are connected to R6；The collector and emitter of Q2
It is formed together the base stage that parallel circuit one end is connected to Q1 with feedback network circuit and discharge loop, the other end is connected to exchange
End.That is the collector of the Q2 base stage that is connected to Q1, the emitter of Q2 are connected to exchange end.
Here the cathode of D1 is connected to exchange end, and the anode of D1 is connected to the emitter of Q3；The ground level of the Q3 is connected to
DC terminal, the collector of Q3 are connected on the circuit between the R4 and R5.
It here include resistance R1, resistance R2, resistance R3 and capacitor C2 between the ground level and DC terminal of Q3, in which: resistance R1
One end is connected to DC terminal, and the R1 other end is connected in parallel to the R2 and R3；The one end R2 is connected to R1, the R2 other end and institute
State C2 earth；The one end R3 and R2 are connected in parallel R1, which is connected in parallel the ground level of Q3 with the C2；The C2 mono-
End and the R2 earth, the C2 and R3 are connected in parallel the ground level of Q3.
Here Q1 can use Darlington transistor, and Darlington transistor refers to that two triodes are connected together, the pole of Darlington transistor
Property be first triode polarity, the amplification factor of Darlington transistor is the product of two triode amplification factors, therefore reaches woods
The pipe that pauses is normally acting in highly sensitive amplifying circuit such as high-power switching circuit, plays a part of to amplify very small signal.
In embodiments of the present invention shown in Fig. 2 and Fig. 3 in Q1, Q2, Q3 all use NPN silicon cast triode.Wherein, this
In Q1, Q2, Q3 in have base stage B, collector C and emitter E, the working condition of triode is determined by the voltage potential of each pole:
As emitter voltage gesture UELess than base voltage gesture UB, and base voltage gesture UBLess than collector voltage gesture UCWhen, i.e.,
UE< UB< UCWhen, the triode of NPN silicon cast is in magnifying state；
As emitter voltage gesture UEGreater than base voltage gesture UB, and collector voltage gesture UCGreater than base voltage gesture UBWhen, i.e.,
UE> UBAnd UC> UBWhen, the triode of NPN silicon cast is in off state；
As base voltage gesture UBGreater than emitter voltage gesture UE, and base voltage gesture UBGreater than collector voltage gesture UCWhen, i.e.,
UB> UEAnd UB> UCWhen, the triode of NPN silicon cast is in a saturated state.
Specifically, the collector C of the Q1 is connected with direct-flow input end Vin, the base stage B of Q1 is inputted by R4, R5 and direct current
Vin is held to be connected, the emitter E of Q1 realizes direct current output to load end RL by R6；Therefore in the AC impedance circuit course of work
In, the base voltage gesture U of Q1BLess than collector voltage gesture UC1, and emitter voltage gesture UE1Less than base voltage gesture UB1, Da Lin
The pipe Q1 that pauses is constantly in the state of amplification in course of normal operation, and Q1 plays a part of to amplify very small signal.
Specifically, the collector C of the base stage B and Q2 of Q1 is connected, the emitter E of Q1 is connected with the base stage B of Q2；The base stage of Q2
B is connected on the route of Q1 to R6；In the high AC impedance circuit course of work, the emitter voltage gesture U of Q2E2Greater than base stage electricity
Press gesture UB2, the collector voltage gesture U of Q2C2Base voltage gesture U greater than Q2B2, Q2 is constantly in cut-off in course of normal operation
State.In addition, being in off state in Q2, the Q2 and resistance R6 play the role of limitation output size of current jointly；According to
The characteristic of NPN silicon cast triode, the voltage V between base stage B and emitter E on Q2BEThe V in off stateBE≤ 0.7V,
The maximum current of the high AC impedance circuit at DC output end OUT be
First capacitor C1, resistance R7 in the embodiment of the present invention collectively constitute feedback network circuit, the feedback network circuit
The connection of the base stage of one end and Q1, one end is connect with DC output end；R8 provides discharge loop for C1, the discharge loop and feedback net
Network circuit is formed together parallel circuit, and in the base stage of an end Jie Q1, one end is connect with DC output end.
D1, Q3, R1, R2, R3 and C2 in the embodiment of the present invention collectively constitute short circuit, overcurrent protection network.
Specifically, the base stage B of Q3 is connected by R3, R1 with direct-flow input end Vin；The collector C of Q3 is accessed in R4 and R5
Between route on；The emitter E of Q3 is connected to DC current output end vo ut by diode D1.Therefore, in AC impedance
Circuit is in course of normal operation, the emitter voltage gesture U of Q3E3Greater than base voltage gesture UB3, and the collector voltage gesture on Q3
UC3Greater than base voltage gesture UB3, therefore Q3 is constantly in the state of cut-off in course of normal operation.Short circuit, overcurrent at this time
Network is protected not work, the voltage V of DC output end VoutoutWith DC output end voltage VinRising and rise.
The maximum current of the AC impedance circuit at DC output end Vout beThat is at the 7th in shown in Fig. 2 and Fig. 3
Maximum current beIt should be noted that in embodiments of the present invention, can 7 shown in the figure at load voice, FSK etc. and hand over
The transmitting that signal is used for information is flowed, the concrete type of signal is not construed as limiting in embodiments of the present invention.
Once and electric current consumed by the AC signal loaded at Fig. 2 or shown in Fig. 37 is closeIt can go out at 7
Existing overcurrent or the situation of short circuit, at this time the voltage potential U at 77It can drop to and be infinitely close to zero；Due to the emitter voltage gesture of Q3
UE3With the voltage potential V at figure shown 77It is equal, therefore the emitter voltage U of Q3E3Also it can accordingly drop to and be infinitely close to zero；Due to
The emitter voltage U of Q3E3It is infinitely close to zero, therefore in Q3, the emitter voltage gesture UE3 on Q3 is less than the base voltage on Q1
Gesture UB1, and the collector voltage gesture UC3 on Q3 is greater than the base voltage gesture UB1 on Q1, third transistor Q3 is by cut-off shape at this time
State becomes on state.
Due to third transistor Q3Conducting, thus shown in Fig. 2 or Fig. 3 in voltage potential at 4 can reduce, correspondingly, reach
The base voltage gesture U of Islington pipe Q1B1When can also reduce, therefore overcurrent or short circuit occur, Darlington transistor Q1 can be in weak conducting
State；Under weak on state, the passable collector current I of Darlington transistor Q1C1Very little, the function of Darlington transistor Q1 consumption at this time
Rate than it is fully on when it is much smaller；The conducting of third transistor Q3, the voltage being loaded on resistance R5 can reduce, but due to direct current
The input voltage V at endinIt is constant, therefore be loaded into and will increase with the voltage of the concatenated resistance R4 of resistance R5, corresponding resistor R4's disappears
Wasted work rate also will increase, i.e. dissipated power caused by resistance R4 needs to consume because of short circuit or overcurrent.
In high AC impedance circuit provided in an embodiment of the present invention, short circuit or overcurrent is occurring, by by the three or three pole
Pipe Q3 becomes on state from off state, so that the power of Darlington transistor Q1 is transferred on resistance R4, makes Darlington transistor Q1
It is protected when short circuit or overcurrent occurs, avoids cause thermal damage of the Darlington transistor Q1 in overcurrent or short circuit.Due to resistance
R4 needs to dissipate input voltage VinMost of power of generation, therefore resistance R4Selection need to be according to input voltage VinIt determines,
That is resistance R4Maximum power should be greater than
After overcurrent or short circuit disappear, 7 in figure at be linked into the high AC impedance circuit again, at this time 7 in figure
Locate voltage potential U7It begins to ramp up, the emitter voltage U of Q3E3Also the state before overcurrent or short circuit occurs can be accordingly risen to, because
This Q3 comes back to off state by state；After Q3 is restored back to off state, at this time 4 in figure at voltage potential can increase,
Correspondingly, the base voltage gesture U of Darlington transistor Q1B1Also can rise, therefore Darlington Q1 can also be come back to by weak on state
Magnifying state, the high AC impedance circuit restore normal.
The short circuit, the setting of overcurrent protection network can be in high AC impedance circuits when short circuit, overcurrent occurs
Important amplifier element Darlington transistor Q1 protected；In addition, after short circuit, over-current phenomenon avoidance disappear, the high AC impedance circuit
Can be with self- recoverage to normal condition, practicability is good.
Fig. 2 is the equivalent circuit diagram of AC impedance circuit when short circuit, overcurrent protection network are inactive in the embodiment of the present invention,
Or only play circuit diagram under high AC impedance.When short circuit, overcurrent protection network are inactive, high AC impedance circuit
Circuit diagram can be reduced to equivalent circuit diagram as shown in Figure 2；It should be noted that since short circuit, overcurrent protection network do not open
Dynamic, the second triode Q2 does not also have an effect, therefore can ignore the second triode Q2 in isoboles.
When high AC impedance circuit is in quiescent point, there is an original excitation δ V (to can be voice, FSK at this time
Equal AC signals) it is loaded at 7 in figure, the excitation can partially be decayed when load, set attenuation coefficient as k1；Then, this swashs
Encouraging can be transmitted at 5 in figure by feedback network first capacitor C1, resistance R7, set attenuation coefficient here as k2, therefore 5 in figure
The voltage at place can generate the variation of k1*k2* δ V, and due to VinIt is constant, it then passes through the base current at R4, R5 and changes,
It can indicate are as follows:
According to the amplification characteristic of triode, triode Q1 is in magnifying state, therefore in triode Q1, it is believed that on Q1
Voltage V between collector, emitterCEWith base current IBIt is directly proportional, this all proportionality coefficient be β, the collector C of triode Q1,
Voltage change between emitter E can indicate are as follows:
By resistance R6Attenuation coefficient be k3, at this time 7 in figure at voltage change can state are as follows:
Thus, δ V7It, will not be by when original excitation δ V only being needed to be loaded into 7 in figure here with the same phase of original excitation δ V
Decaying, as long as meeting following formula:
Therefore, as long as meeting above-mentioned equation, it is infinitely great that the circuit of figure two, which can be equivalent to a high AC impedance,
Network；Wherein, direct-flow input end VinDC power supply is provided, and be loaded at 7 in figure it is ac-excited will not be attenuated, therefore can
Traditional big inductance value inductance can be substituted completely to transmit AC signals, the circuits such as voice, FSK at 7, solved existing big
The problems of inductance value inductance and deficiency.Circuit shown in Fig. 2 is using resistance-capacitance network AC signal from the hair of triode
Emitter feedback maintains original AC signal by network degradation, not can be equivalent to one to base stage by triode amplification
A AC impedance is infinitely great network, therefore, can substitute traditional high inductance value inductance, so reduce the volume of product at
This, and the DC voltage of output end is in controlled range, can satisfy some pairs of voltage change ranges and has certain requirements field
It closes.
Fig. 4 shows the high AC impedance circuit theory schematic diagram based on PNP type triode in the embodiment of the present invention, figure
High AC impedance circuit shown in 4 includes: PNP type triode Q1, resistance R6, resistance R4, resistance R5, capacitor C1, resistance R7, electricity
Hinder R8 and load RL etc..Resistance R6 is in series on the emitter of Q1, the emitter of Q1 is based on R6 and is connected to DC terminal；The base of Q1
Base resistance R4 and R5 are in series on extremely, the base stage of Q1 is based on base resistance and is connected to DC terminal；The collector of Q1 is connected to bear
End is carried, i.e., the output end that the collector of Q1 may be implemented to extend outside direct current output to the collector of load end and Q1 is loaded with
End is exchanged, and is realized at direct current output and AC signal to load RL simultaneously；It is provided with and exchanges in the base stage of exchange end and Q1
Signal feedback circuit, AC signal feedback circuit include feedback network circuit and discharge loop, the feedback network circuit and institute
It states discharge loop and forms the base stage that parallel circuit one end is connected to the Q1, the other end is connected to exchange end, specifically, the feedback
Lattice network includes capacitor C1 and resistance R7, which includes resistance R8, and R8 here provides discharge loop for C1.
It should be noted that Q1 shown in Fig. 4 can be positive-negative-positive single-stage or multilevel semiconductor triode etc..
Here it sets circuit shown in Fig. 4 and is in quiescent point (i.e. Q1 is in amplification region), at this time, it is assumed that have an original
Begin that δ V (can be the AC signals such as voice, FSK) is motivated to be loaded at 47, which can partially be decayed, it is assumed that attenuation coefficient
For k1, later, the excitation can be by feedback network C1, R7 to 45 at, set attenuation coefficient is k2, thus 45 in figure at
Voltage has the variation of k1*k2* δ V, and since Vin is constant, then passing through the base current at R4, R5 changes, and can indicate
Are as follows:
According to the amplification characteristic of BJT triode, Q1 works in amplification region, and the base current of middle Q1 and C, E shown in Fig. 4 are extremely electric
It is pressed into direct ratio, sets its proportionality coefficient as β, therefore C, E pole tension variation of Q1 can indicate are as follows:
Voltage change between shown in Fig. 4 41 and 47 are as follows:
And due to the pole the C Vin of Q1 be it is constant, 7 in figure at voltage change can be expressed as
It follows that δ V7With the same phase of original excitation δ V, it is loaded at 7 in figure and is not attenuated if necessary to original excitation δ V,
Meet following formula:
By analyzing above, as long as meeting above formula, circuit shown in Fig. 4 can be equivalent to an AC impedance as infinity
Network, Vin is direct-flow input end, and be loaded at 47 shown in Fig. 4 it is ac-excited will not be attenuated, therefore can be
AC signal is loaded at 47 to transmit voice, FSK etc., and the circuit can substitute traditional big inductance value inductance completely.
Fig. 2 can be applied in elevator intercom system to high AC impedance circuit shown in Fig. 4, to realize elevator intercommunication
System is based on bus and each intercommunication terminal is powered, and simultaneously using same a pair of of bus transfer voice signal, in the straight of bus supply
It flows end and exchanges the AC impedance circuit being arranged in the embodiment of the present invention between end, voice signal or exchange in bus can be maintained
Signal will not be decayed by transmission network, and can be equivalent to an AC impedance is infinitely great network, can substitute traditional height
Inductance value inductance, and then reduce the volume and cost of product, and the DC voltage of output end can preferably expire in controlled range
What voltage change range required on sufficient elevator device is applicable in.
Fig. 2 can be applied to realize direct current supply to load based on same route to high AC impedance circuit shown in Fig. 4
End is provided with this between the DC terminal in system and exchange end with based on exchanging on end transmission signal to the system of load end
AC impedance circuit in inventive embodiments can maintain the AC signal on same route not decay to transmission network,
It can be equivalent to the network of one high AC impedance infinity, reduce DC terminal end and decay to the signal at exchange end end, can replace
For traditional high inductance value inductance, and then reduce the volume and cost of product, and the DC voltage of output end is in controlled range,
Can preferably meet system electrification pressure variation range require be applicable in.
It should be noted that the DC output end in the present invention is DC terminal, ac output end is to exchange end.
Those of ordinary skill in the art will appreciate that all or part of the steps in the various methods of above-described embodiment is can
It is completed with instructing relevant hardware by program, which can be stored in a computer readable storage medium, storage
Medium may include: read-only memory (ROM, Read Only Memory), random access memory (RAM, Random
Access Memory), disk or CD etc..
In addition, being provided for the embodiments of the invention high AC impedance circuit above and its application system has carried out detailed Jie
It continues, used herein a specific example illustrates the principle and implementation of the invention, and the explanation of above embodiments is only
It is to be used to help understand method and its core concept of the invention；At the same time, for those skilled in the art, according to this hair
Bright thought, there will be changes in the specific implementation manner and application range, in conclusion the content of the present specification should not manage
Solution is limitation of the present invention.
Claims (10)
1. a kind of high AC impedance circuit, which is characterized in that the high AC impedance circuit is placed between DC terminal and exchange end,
The high AC impedance circuit includes the first triode Q1, and the DC terminal is based on Q1 input dc power to exchanging end；In direct current
It is in series with base resistance in the base stage of end and the Q1, AC signal feedback electricity is provided in the base stage of exchange end and the Q1
Road.
2. high AC impedance circuit as described in claim 1, which is characterized in that the AC signal feedback circuit includes feedback
Lattice network and discharge loop, the feedback network circuit and the discharge loop form parallel circuit one end and are connected to the Q1
Base stage, the other end be connected to exchange end.
3. high AC impedance circuit as described in claim 1, which is characterized in that the base resistance includes resistance R4 and resistance
R5, the R4 and the R5 are cascaded, and the R4 is connected to DC terminal, and the R5 is connected to the base stage of Q1.
4. high AC impedance circuit as claimed in claim 2, which is characterized in that the feedback network circuit include capacitor C1 and
Resistance R7, the discharge loop include resistance R8；The R8 provides discharge loop for the C1.
5. such as the described in any item high AC impedance circuits of Claims 1-4, which is characterized in that the Q1 be NPN type single-stage or
Multilevel semiconductor triode or be positive-negative-positive single-stage or multilevel semiconductor triode.
6. high AC impedance circuit as claimed in claim 5, which is characterized in that the high AC impedance circuit further includes current limliting
Circuit, the current-limiting circuit includes the second triode Q2 and resistance R6, the Q1 are NPN type transistor, and the Q2 is
NPN type transistor, in which:
The emitter of the base stage of the Q2 and the Q1 are connected to R6；
The collector of the Q2 is connected to the base stage of the Q1；
The emitter of the Q2 is connected to exchange end；
The collector and emitter of the Q2 and the feedback network circuit and discharge loop are formed together parallel circuit one end company
Then the base stage of the Q1, the other end are connected to exchange end.
7. high AC impedance circuit as claimed in claim 6, which is characterized in that the high AC impedance circuit further includes two poles
Pipe D1 and third transistor Q3, the Q3 are NPN type triode, in which:
The cathode of the D1 is connected to exchange end, and the anode of the D1 is connected to the emitter of Q3；
The base stage of the Q3 is connected to DC terminal, and the collector of the Q3 is connected on the circuit between the R4 and R5.
8. high AC impedance circuit as claimed in claim 7, which is characterized in that include electricity between the base stage and DC terminal of the Q3
Hinder R1, resistance R2, resistance R3 and capacitor C2, in which:
Described one end R1 is connected to DC terminal, and the R1 other end is connected in parallel to the R2 and R3；
Described one end R2 is connected to R1, the R2 other end and the C2 earth；
Described one end R3 and R2 are connected in parallel R1, and the R3 other end and the C2 are connected in parallel the ground level of Q3；
Described one end C2 and the R2 earth, the C2 and the R3 are connected in parallel the base stage of Q3.
9. a kind of elevator intercom system, which is characterized in that the elevator intercom system is based on bus and each intercommunication terminal is powered, and
Simultaneously using with a pair of of bus transfer voice signal, it is arranged between the DC terminal and exchange end of bus supply just like claim
1 to 8 described in any item high AC impedance circuits.
10. a kind of system, which is characterized in that the system is based on handing over based on same route realization direct current supply to load end
It flows end and transmits signal to load end, high friendship as claimed in any one of claims 1 to 8 is provided between DC terminal and exchange end
Flow resistance reactive circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910117736.XA CN109802654A (en) | 2019-02-15 | 2019-02-15 | A kind of high AC impedance circuit and its application system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910117736.XA CN109802654A (en) | 2019-02-15 | 2019-02-15 | A kind of high AC impedance circuit and its application system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109802654A true CN109802654A (en) | 2019-05-24 |
Family
ID=66560908
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910117736.XA Pending CN109802654A (en) | 2019-02-15 | 2019-02-15 | A kind of high AC impedance circuit and its application system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109802654A (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101141597A (en) * | 2006-09-08 | 2008-03-12 | 深圳Tcl新技术有限公司 | Wide-range video output circuit |
| US7772927B1 (en) * | 2007-10-04 | 2010-08-10 | Rf Micro Devices, Inc. | Active bias Darlington amplifier |
| CN101877576A (en) * | 2009-04-30 | 2010-11-03 | 华为技术有限公司 | Filter circuit and communication equipment provided with same |
| CN203178842U (en) * | 2013-03-05 | 2013-09-04 | 丽水职业技术学院 | Alternating-current constant flow source character load circuit for sensor |
| CN203193572U (en) * | 2012-06-07 | 2013-09-11 | 李志鹏 | Low-voltage driving integrated amplifier for automobile control circuit |
| CN204993341U (en) * | 2015-07-29 | 2016-01-20 | 泉州品荣商贸有限公司 | Elevator intercom circuit |
| CN209375125U (en) * | 2019-02-15 | 2019-09-10 | 广东寰宇电子科技股份有限公司 | A kind of DC protection circuit and elevator intercom system and direct current output system |
| CN209488537U (en) * | 2019-02-15 | 2019-10-11 | 广东寰宇电子科技股份有限公司 | A kind of high AC impedance circuit and its application system |
-
2019
- 2019-02-15 CN CN201910117736.XA patent/CN109802654A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101141597A (en) * | 2006-09-08 | 2008-03-12 | 深圳Tcl新技术有限公司 | Wide-range video output circuit |
| US7772927B1 (en) * | 2007-10-04 | 2010-08-10 | Rf Micro Devices, Inc. | Active bias Darlington amplifier |
| CN101877576A (en) * | 2009-04-30 | 2010-11-03 | 华为技术有限公司 | Filter circuit and communication equipment provided with same |
| CN203193572U (en) * | 2012-06-07 | 2013-09-11 | 李志鹏 | Low-voltage driving integrated amplifier for automobile control circuit |
| CN203178842U (en) * | 2013-03-05 | 2013-09-04 | 丽水职业技术学院 | Alternating-current constant flow source character load circuit for sensor |
| CN204993341U (en) * | 2015-07-29 | 2016-01-20 | 泉州品荣商贸有限公司 | Elevator intercom circuit |
| CN209375125U (en) * | 2019-02-15 | 2019-09-10 | 广东寰宇电子科技股份有限公司 | A kind of DC protection circuit and elevator intercom system and direct current output system |
| CN209488537U (en) * | 2019-02-15 | 2019-10-11 | 广东寰宇电子科技股份有限公司 | A kind of high AC impedance circuit and its application system |
Non-Patent Citations (1)
| Title |
|---|
| 李黎明;黄忠全;郑小林;: "基于阻抗原理的磁弹性传感器测试仪设计", 传感器与微系统, no. 12 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106972769A (en) | A kind of light current electrical load overvoltage crowbar | |
| CN106933288A (en) | A kind of low-power consumption is without the outer capacitor type low pressure difference linear voltage regulator of piece | |
| CN209488537U (en) | A kind of high AC impedance circuit and its application system | |
| CN106647919B (en) | Host device of two-bus communication circuit and two-bus communication circuit | |
| CN209375125U (en) | A kind of DC protection circuit and elevator intercom system and direct current output system | |
| US5444777A (en) | Battery feed for telephone line cards | |
| CN109802654A (en) | A kind of high AC impedance circuit and its application system | |
| CN202172267U (en) | An Ethernet interface protection circuit | |
| CN201937463U (en) | Short-circuit current limiting circuit, power supply and loading equipment | |
| CN206850666U (en) | A kind of doubleway output current foldback circuit | |
| CN203434951U (en) | Wide voltage pulse reception isolated circuit | |
| CN202331254U (en) | Current-voltage conversion circuit with over-current protection circuit module | |
| CN108037787A (en) | A kind of A/D chip input voltages limiter protection circuit | |
| CN103338012B (en) | A kind of current-limited power amplification driving circuit of power line carrier communication | |
| CN107046418A (en) | A kind of single live wire power getting circuit | |
| CN205983279U (en) | Linear series connection voltage stabilizing circuit | |
| CN105048976B (en) | A kind of power amplification circuit based on LM3886 chips | |
| CN207083110U (en) | A kind of interchanger with self-protection function | |
| CN202977969U (en) | Efficient protection circuit of laser coupling power source | |
| CN103501396B (en) | Medical communication calling equipment main frame | |
| CN104281188A (en) | Enabling circuit applied to LDO (low-drop out) linear regulator | |
| CN203313135U (en) | Current-limiting power amplification driving circuit in power line carrier communication | |
| US3636266A (en) | Negative impedance line isolators | |
| CN103023439B (en) | A kind of power amplifying system for intelligent substation test system | |
| CN203504643U (en) | Medical communication calling device host machine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |