CN204925217U - Constant current source output current detection device - Google Patents
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- CN204925217U CN204925217U CN201520611739.6U CN201520611739U CN204925217U CN 204925217 U CN204925217 U CN 204925217U CN 201520611739 U CN201520611739 U CN 201520611739U CN 204925217 U CN204925217 U CN 204925217U
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Abstract
The utility model provides a constant current source output current detection device, including the sampling circuit and elementary amplifier circuit who connects gradually, sampling circuit includes the sampling resistor, the one end and the constant current source of sampling resistor are connected, the other end is connected with the load, elementary amplifier circuit includes the current division watch -dog, at least two way regulating circuits, every way regulating circuit all includes regulating electrical resistance and the controllable switch who establishes ties, two inputs of current division watch -dog are connected with the both ends of sampling resistor respectively as two inputs of elementary amplifier circuit, the one end and the output of current division watch -dog of every way regulating circuit are connected, and the other terminal of the capacitor is connected to the ground, the output of current division watch -dog is as elementary amplifier circuit's output. The problem of thereby during present use constant current source general the measuring its output current be difficult to guarantee that the invariable and present current detection device of output current can not be according to the different adjustment the magnification of constant current source is solved. Be applicable to the constant current source output current detection that flies the needle test machine and use.
Description
Technical field
The utility model relates to current detection technology field.Specifically, a kind of constant current source detecting device for output current is related to.
Background technology
Constant current source is the current source that output current remains unchanged, and desirable constant current source is: a) do not change because of the change of load (output voltage); B) do not change because of variation of ambient temperature; C) internal resistance is infinitely great.
Existing most of constant current source has a series of constant-current control circuit therein, but when using constant current source, just substantially the electric current that it exports is not detected, but because of reasons such as device faults, the electric current likely off-design value that constant current source exports, when constant current source is used for testing circuit, so the departing from of constant current source output current, can affect measurement result, if the electric current exported is much bigger than normal, can follow-up circuit be caused damage.
And existing constant current source detecting device for output current, generally can not according to the different adjustment enlargement factor of constant current source, and enlargement factor is improper, may affect the accuracy of testing result.Such as, publication number is CN104102263, name is called in the application for a patent for invention of " a kind of constant-current source circuit of belt current monitoring ", discloses the current detection circuit that can detect constant current source output current.Between the output terminal that this current detection circuit is connected on basic constant-current source circuit and consumer, receive the output current from basic constant-current source circuit, the output current of basic constant current source is detected in real time, and the output current of basic constant-current source circuit is converted to voltage signal is supplied to voltage modulate circuit, voltage modulate circuit exports to comparator circuit after the voltage signal that current detection circuit exports is adjusted to suitable scope, comparator circuit is default setting voltage with reference to voltage transitions, and the voltage after the conditioning of voltage modulate circuit and this setting voltage are compared, and export corresponding control signal to signal holding circuit according to comparative result.Crossing detector circuit in this application for a patent for invention can not according to the difference adjustment enlargement factor of constant current source, and can only be adjusted by voltage modulate circuit, this circuit structure is complicated, takes up room large.
Utility model content
For this reason, when technical problem to be solved in the utility model is to use constant current source at present, its electric current exported of general tree detects, even if detect, its circuit structure also more complicated, take up room large and can not according to the different adjustment enlargement factor of constant current source, thus propose a kind of can according to the difference adjustment enlargement factor of constant current source and the constant current source detecting device for output current taking up room little.
For solving the problems of the technologies described above, the utility model provides following technical scheme:
A kind of constant current source detecting device for output current, comprise the sample circuit and elementary amplifying circuit that connect successively, sample circuit comprises sampling resistor, one end of sampling resistor is connected with constant current source, the other end is connected with load, elementary amplifying circuit comprises current distributing watch-dog, at least two-way regulating circuit, every road regulating circuit all comprises regulating resistance and the gate-controlled switch of series connection, two input ends of current distributing watch-dog are connected with the two ends of sampling resistor respectively as two input ends of elementary amplifying circuit, one end of every road regulating circuit is connected with the output terminal of current distributing watch-dog, other end ground connection, the output terminal of current distributing watch-dog is as the output terminal of elementary amplifying circuit.
Preferably, current distributing watch-dog comprises the first operational amplifier, triode Q, resistance R1 and R2, one end of resistance R1 is connected with the in-phase input end of the first operational amplifier, the other end is as an input end of current distributing watch-dog, one end of resistance R2 is connected with the inverting input of the first operational amplifier, the other end as another input end of current distributing watch-dog, the base stage of triode Q is connected with the output terminal of the first operational amplifier, collector is connected with the other end of resistance R1, emitter is as the output terminal of current distributing watch-dog.
Preferably, also comprise the secondary amplification circuit be connected with elementary amplifying circuit, secondary amplification circuit comprises the second operational amplifier, resistance R157 and resistance R156, the in-phase input end of the second operational amplifier is connected with the output terminal of elementary amplifying circuit as the input end of secondary amplification circuit, one end of resistance R156 is connected with the inverting input of the second operational amplifier, the other end is connected with the output terminal of the second operational amplifier, one end of resistance R157 is connected with the inverting input of the second operational amplifier, another termination reference voltage, the output terminal of the second operational amplifier and the junction of resistance R156 are as the output terminal of secondary amplification circuit.
Preferably, secondary amplification circuit also comprises the reference voltage circuit for providing reference voltage, reference voltage circuit comprises the 3rd operational amplifier, resistance R422 and resistance R413, in-phase input end ground connection, the inverting input of the 3rd operational amplifier are connected with external connection constant voltage source by resistance R422, output terminal is connected with the other end of resistance R157, and one end of resistance R413 is connected with the inverting input of the 3rd operational amplifier, the other end is connected with the output terminal of the 3rd operational amplifier.
Preferably, also comprise the first voltage follower circuit be arranged between elementary amplifying circuit and secondary amplification circuit, first voltage follower circuit comprises four-operational amplifier, and the in-phase input end of four-operational amplifier is connected with the output terminal of elementary amplifying circuit, output terminal is connected with the input end of secondary amplification circuit, inverting input is connected with its output terminal.
Preferably; also comprise the protection circuit be arranged between elementary amplifying circuit and secondary amplification circuit; protection circuit comprises diode D151, diode D152 and resistance R163; diode D151 and D152 series aiding connection; the anode of diode D151 connects the first deboost; the negative electrode of diode D152 connects the second deboost; the junction of diode D151 negative electrode and diode D152 anode is connected with the output terminal of elementary amplifying circuit, the input end of secondary amplification circuit, one end of resistance R163 respectively, the other end ground connection of resistance R163.
Preferably, also comprise the second voltage follower circuit, second voltage follower circuit comprises the 5th operational amplifier and resistance R155, the in-phase input end of the 5th operational amplifier is connected with the output terminal of secondary amplification circuit, and the inverting input of the 5th operational amplifier is connected with its output terminal by resistance R155.
Preferably, the second voltage follower circuit also comprises electric capacity C156, and one end of electric capacity C156 is connected with the in-phase input end of the 5th operational amplifier, other end ground connection.
Technique scheme of the present utility model has the following advantages compared to existing technology:
1. the constant current source detecting device for output current that provides of the utility model, by sampling resistor, constant current source output current is converted to voltage signal, and inputing to processor circuit after being amplified by elementary amplifying circuit, processor circuit show that after algorithm process whether the electric current that this constant current source exports is constant.Its elementary amplifying circuit is provided with multichannel regulating circuit, makes this device can adjust enlargement factor according to the difference of constant current source or other actual needs by closed different regulating circuit.This current sensing means solves the electric current do not exported constant current source in prior art and detects thus cannot determine the problem whether output current is stable and can not adjust the problem of the enlargement factor of sample circuit according to the difference of constant current source, achieve the Real-Time Monitoring to constant current source output current, can Timeliness coverage constant current source output current skew, ensure that accuracy and the security of subsequent conditioning circuit.In addition, also ensure that the magnitude range exporting electric signal simultaneously, not only can prevent from, because the reasons such as interference loss cause measuring result error comparatively large, follow-up treatment circuit can also being protected.
2. the constant current source detecting device for output current that provides of the utility model, its elementary amplifying circuit is not use discrete components and parts to build, but use high side current distributing watch-dog (INA168NA of TI), therefore can greatly reduce the space that this device takies, and common mode interference can be suppressed well.
Accompanying drawing explanation
Fig. 1 is the elementary amplification circuit diagram of a kind of constant current source detecting device for output current of the utility model embodiment;
Fig. 2 is the circuit diagram of a kind of constant current source detecting device for output current except elementary amplifying circuit of the utility model embodiment.
Embodiment
In order to make those skilled in the art person understand the utility model content better, below in conjunction with drawings and Examples, technical scheme provided by the utility model is described in further detail.
As illustrated in fig. 1 and 2, present embodiments provide a kind of constant current source detecting device for output current, comprise the sample circuit and elementary amplifying circuit that connect successively, sample circuit comprises sampling resistor Rs, one end of sampling resistor Rs is connected with constant current source, the other end is connected with load, elementary amplifying circuit comprises current distributing watch-dog, at least two-way regulating circuit, every road regulating circuit all comprises regulating resistance and the gate-controlled switch of series connection, two input ends of current distributing watch-dog are connected with the two ends of sampling resistor Rs respectively as two input ends of elementary amplifying circuit, one end of every road regulating circuit is connected with the output terminal of current distributing watch-dog, other end ground connection, the output terminal of current distributing watch-dog is as the output terminal of elementary amplifying circuit.Particularly, current distributing watch-dog comprises the first operational amplifier U1, triode Q, resistance R1 and R2, one end of resistance R1 is connected with the in-phase input end of the first operational amplifier U1, the other end is as an input end of current distributing watch-dog, one end of resistance R2 is connected with the inverting input of the first operational amplifier U1, the other end as another input end of current distributing watch-dog, triode Q base stage is connected with the output terminal of the first operational amplifier U1, collector is connected with the other end of resistance R1, emitter is as the output terminal of current distributing watch-dog.
Particularly, above-mentioned elementary amplification circuit output end is connected with processor circuit, this processor circuit comprises AD sample circuit and processor etc., processor is transferred to after the sampling electric signal amplified through elementary amplifying circuit is converted to digital signal, processor obtains constant current source output current after algorithm process, therefore can judge that whether the electric current that constant current source exports is constant, and carry out follow-up process according to this testing result.The resistance of above-mentioned resistance R1 and resistance R2 is equal, is all such as 5K Ω.Also have, regulating circuit specifically can be four tunnels, comprises respectively: the regulating resistance RL4 of the regulating resistance RL3 of the regulating resistance RL2 of the regulating resistance RL1 of series connection and gate-controlled switch U153B, series connection and gate-controlled switch U153C, series connection and gate-controlled switch U153D, series connection and gate-controlled switch U153A.The enlargement factor of this elementary amplifying circuit is that adjusting resistance value on closed regulating circuit is divided by resistance R1 resistance, therefore, gate-controlled switch on closed different adjustment circuit, the enlargement factor of elementary amplifying circuit is different, and therefore this each road regulating circuit is used for the enlargement factor adjusting elementary amplifying circuit according to actual needs.And the gate-controlled switch of each road regulating circuit is controlled by processor, its control end is connected with the control output end mouth of processor respectively.In other embodiments, the regulating circuit of other numbers also can be set according to actual needs.
Discrete component is used to build elementary amplifying circuit in the conventional mode, namely differential amplifier circuit takes up room larger, the constant current source detecting device for output current that the present embodiment provides adopts current distributing watch-dog, be specially the INA168NA height side current distributing watch-dog of TI, the end of oppisite phase of the in-phase end of high pressure termination current distributing watch-dog (INA168NA) of sampling resistor Rs, low pressure termination current distributing watch-dog (INA168NA) of sampling resistor Rs.Adopt this differential amplifier circuit well can also suppress common mode interference.
In sum, the constant current source detecting device for output current that the present embodiment provides, whether the electric current that can detect constant current source output is in real time constant, prevent the accuracy affecting the testing circuit be connected with constant current source because of the variation of constant current source output current, or the load that other are connected with constant current source is impacted.Regulating circuit can also be utilized according to actual needs to adjust the enlargement factor of elementary amplifying circuit, and such as, when constant current source changes, the change of its output current greatly, just can regulate the enlargement factor of elementary amplifying circuit.In addition, use current distributing watch-dog as the amplifying device of elementary amplifying circuit in this device, compared with the elementary amplifying circuit using discrete component to build, it takes up room smaller.
After the constant current source calibration of current most of flying probe tester, be all defaulted as invariable in measuring process.But in measuring process, constant current source likely changes, there is certain error in the possibility of result therefore measured, and cannot meet the requirement of modern flying probe tester to high precision, high reliability.The constant current source detecting device for output current that the present embodiment provides, can be used as the Constant current source sense device of flying probe tester, and whether the output current that can detect constant current source is in real time constant, thus can improve the measuring accuracy of flying probe tester.
Particularly, the constant current source detecting device for output current that this example provides also comprises the secondary amplification circuit be connected with elementary amplifying circuit, this secondary amplification circuit comprises the second operational amplifier U3A, resistance R157 and resistance R156, the in-phase input end of the second operational amplifier U3A is connected with the output terminal of elementary amplifying circuit as the input end of secondary amplification circuit, one end of resistance R156 is connected with the inverting input of the second operational amplifier U3A, the other end is connected with the output terminal of the second operational amplifier U3A, one end of resistance R157 is connected with the inverting input of the second operational amplifier U3A, another termination reference voltage, the output terminal of the second operational amplifier U3A and the junction of resistance R156 are as the output terminal of secondary amplification circuit.Particularly, the reference voltage of this secondary amplification circuit is provided by reference voltage circuit, reference voltage circuit comprises the 3rd operational amplifier U4B, resistance R422 and resistance R413, in-phase input end ground connection, the inverting input of the 3rd operational amplifier U4B are connected with external connection constant voltage source by resistance R422, output terminal is connected with the other end of resistance R157, and one end of resistance R413 is connected with the inverting input of the 3rd operational amplifier U4B, the other end is connected with the output terminal of the 3rd operational amplifier U4B.Particularly, second operational amplifier U3A is AD8512AR type amplifier, the resistance of resistance R156 is 20K Ω (error range of permission is 5%), the resistance of resistance R157 is 2K Ω (error range of permission is 5%), the power input of the second operational amplifier U3A is also by electric capacity C154 ground connection, and the size of this electric capacity C154 is 120NF (error range of permission is 10%).3rd operational amplifier U4B specifically can be NJM4565 type amplifier, and the resistance of resistance R422 specifically can be 12K Ω (error range of permission is 1%), and the resistance of resistance R413 specifically can be 13K Ω (error range of permission is 1%).
In the constant current source detecting device for output current that the present embodiment provides, the voltage signal values after elementary amplifying circuit amplifies is smaller, may there is interference or decay, therefore also need to arrange secondary amplification circuit in transmitting procedure.After arranging secondary amplification circuit, namely follow-up processor circuit is connected with the output terminal of this secondary amplification circuit.The enlargement factor of this secondary amplification circuit is 1+R156/R157, can amplify the voltage signal after the amplification of elementary amplifying circuit further, improve the measuring accuracy of this pick-up unit.
In addition, external connection constant voltage source provides stable voltage for reference voltage circuit, makes reference voltage circuit can provide stable reference voltage for secondary amplification circuit, thus ensures that the operational amplifier of secondary amplification circuit can the work of normal table ground.
Preferably, this constant current source detecting device for output current also comprises the first voltage follower circuit be arranged between elementary amplifying circuit and secondary amplification circuit, first voltage follower circuit comprises four-operational amplifier U2B, and the in-phase input end of four-operational amplifier U2B is connected with the output terminal of elementary amplifying circuit, output terminal is connected with the input end of secondary amplification circuit, inverting input is connected with its output terminal.The input impedance that this first voltage follower circuit can improve the late-class circuit of elementary amplifying circuit reduces the loss of sampled voltage signal, and can the driving force of intensifier circuit.This four-operational amplifier U2B is specially NJM4565 type amplifier.
Preferably, the constant current source detecting device for output current that the present embodiment provides also comprises the protection circuit be arranged between elementary amplifying circuit and secondary amplification circuit, protection circuit comprises diode D151, diode D152 and resistance R163, diode D151 and D152 series aiding connection, the anode of diode D151 meets the first deboost V1, the negative electrode of diode D152 meets the second deboost V2, the junction of diode D151 negative electrode and diode D152 anode respectively with the output terminal of elementary amplifying circuit, the input end of secondary amplification circuit, one end of resistance R163 connects, the other end ground connection of resistance R163.This protection circuit comprises diode D151 and D152, output voltage can be limited between the first deboost V1 and the second deboost V2, and wherein, the first deboost V1 is greater than the second deboost V2, and this second deboost V2 can be+15V.When uncontrollable situation appears in elementary amplifying circuit, subsequent conditioning circuit may be caused to be burned, and this protection circuit limit the voltage outputting to subsequent conditioning circuit, therefore can protect subsequent conditioning circuit.This protection circuit concrete can be arranged between the first voltage follower circuit and secondary amplification circuit; diode D151 negative electrode is connected with the output terminal of four-operational amplifier U2B by resistance R165 with the junction of diode D152 anode, and the resistance of this resistance R165 is 2K Ω (error range of permission is 5%).And the concrete resistance of resistance R163 can be 20K Ω (error range of permission is 5%).
Preferably, the constant current source detecting device for output current that the present embodiment provides also comprises the second voltage follower circuit, second voltage follower circuit comprises the 5th operational amplifier U3B and resistance R155, the in-phase input end of the 5th operational amplifier U3B is connected with the output terminal of secondary amplification circuit, and the inverting input of the 5th operational amplifier U3B is connected with its output terminal by resistance R155.Wherein, 5th operational amplifier U3B specifically can be AD8512AR type amplifier, and its power input can be connected with the first deboost V1, be also connected rear ground connection with electric capacity C155 simultaneously, and electric capacity C155 is specially 120NF, resistance R155 is specially 0 Ω, allows the error of 5%.Particularly, the in-phase input end of the 5th operational amplifier U3B is connected with the output terminal of secondary amplification circuit by resistance R161, and the resistance of this resistance R161 is 10K Ω (error range of permission is 1%).This second voltage follower circuit can improve the input impedance of the late-class circuit of secondary amplification circuit, reduces the loss of sampled voltage signal, also can play isolation, improve the effects such as load capacity.
In addition, above-mentioned second voltage follower circuit also comprises electric capacity C156, and one end of electric capacity C156 is connected with the in-phase input end of the 5th operational amplifier U3B, other end ground connection.This electric capacity C156 can filtering interfering, to improve the accuracy of testing result.This electric capacity C156 specifically can be 820PF.
Obviously, above-described embodiment is only for clearly example being described, and the restriction not to embodiment.For those of ordinary skill in the field, can also make other changes in different forms on the basis of the above description.Here exhaustive without the need to also giving all embodiments.And thus the apparent change of extending out or variation be still among the protection domain that the utility model creates.
Claims (8)
1. a constant current source detecting device for output current, comprise the sample circuit and elementary amplifying circuit that connect successively, it is characterized in that, described sample circuit comprises sampling resistor, one end of described sampling resistor is connected with described constant current source, the other end is connected with load, described elementary amplifying circuit comprises current distributing watch-dog, at least two-way regulating circuit, every road regulating circuit all comprises regulating resistance and the gate-controlled switch of series connection, two input ends of described current distributing watch-dog are connected with the two ends of described sampling resistor respectively as two input ends of described elementary amplifying circuit, one end of regulating circuit described in every road is connected with the output terminal of described current distributing watch-dog, other end ground connection, the output terminal of described current distributing watch-dog is as the output terminal of described elementary amplifying circuit.
2. constant current source detecting device for output current as claimed in claim 1, it is characterized in that, described current distributing watch-dog comprises the first operational amplifier, triode Q, resistance R1 and R2, one end of described resistance R1 is connected with the in-phase input end of described first operational amplifier, the other end is as an input end of described current distributing watch-dog, one end of resistance R2 is connected with the inverting input of the first operational amplifier, the other end is as another input end of described current distributing watch-dog, the base stage of described triode Q is connected with the output terminal of described first operational amplifier, collector is connected with the other end of described resistance R1, emitter is as the output terminal of described current distributing watch-dog.
3. constant current source detecting device for output current as claimed in claim 1 or 2, it is characterized in that, also comprise the secondary amplification circuit be connected with described elementary amplifying circuit, described secondary amplification circuit comprises the second operational amplifier, resistance R157 and resistance R156, the in-phase input end of described second operational amplifier is connected with the output terminal of described elementary amplifying circuit as the input end of described secondary amplification circuit, one end of described resistance R156 is connected with the inverting input of described second operational amplifier, the other end is connected with the output terminal of described second operational amplifier, one end of described resistance R157 is connected with the inverting input of described second operational amplifier, another termination reference voltage, the output terminal of described second operational amplifier and the junction of described resistance R156 are as the output terminal of described secondary amplification circuit.
4. constant current source detecting device for output current as claimed in claim 3, it is characterized in that, described secondary amplification circuit also comprises the reference voltage circuit for providing reference voltage, described reference voltage circuit comprises the 3rd operational amplifier, resistance R422 and resistance R413, the in-phase input end ground connection of described 3rd operational amplifier, inverting input is connected with external connection constant voltage source by described resistance R422, output terminal is connected with the other end of described resistance R157, one end of described resistance R413 is connected with the inverting input of described 3rd operational amplifier, the other end is connected with the output terminal of described 3rd operational amplifier.
5. constant current source detecting device for output current as claimed in claim 3, it is characterized in that, also comprise the first voltage follower circuit be arranged between described elementary amplifying circuit and described secondary amplification circuit, described first voltage follower circuit comprises four-operational amplifier, described four-operational amplifier in-phase input end is connected with the output terminal of described elementary amplifying circuit, output terminal is connected with the input end of described secondary amplification circuit, inverting input is connected with its output terminal.
6. constant current source detecting device for output current as claimed in claim 3, it is characterized in that, also comprise the protection circuit be arranged between described elementary amplifying circuit and described secondary amplification circuit, described protection circuit comprises diode D151, diode D152 and resistance R163, described diode D151 and D152 series aiding connection, the anode of described diode D151 connects the first deboost, the negative electrode of described diode D152 connects the second deboost, the junction of described diode D151 negative electrode and described diode D152 anode respectively with the output terminal of described elementary amplifying circuit, the input end of described secondary amplification circuit, one end of described resistance R163 connects, the other end ground connection of described resistance R163.
7. constant current source detecting device for output current as claimed in claim 3, it is characterized in that, also comprise the second voltage follower circuit, described second voltage follower circuit comprises the 5th operational amplifier and resistance R155, the in-phase input end of described 5th operational amplifier is connected with the output terminal of described secondary amplification circuit, and the inverting input of described 5th operational amplifier is connected with its output terminal by described resistance R155.
8. constant current source detecting device for output current as claimed in claim 7, it is characterized in that, described second voltage follower circuit also comprises electric capacity C156, and one end of described electric capacity C156 is connected with the in-phase input end of described 5th operational amplifier, other end ground connection.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520611739.6U CN204925217U (en) | 2015-08-13 | 2015-08-13 | Constant current source output current detection device |
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| CN201520611739.6U CN204925217U (en) | 2015-08-13 | 2015-08-13 | Constant current source output current detection device |
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| CN204925217U true CN204925217U (en) | 2015-12-30 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106771476A (en) * | 2016-11-25 | 2017-05-31 | 西安微电子技术研究所 | A kind of high-tension current supervisory circuit |
| CN110486893A (en) * | 2019-08-30 | 2019-11-22 | 海信（山东）空调有限公司 | A kind of Defrost method and air conditioner of air conditioner |
| CN114325043A (en) * | 2021-12-16 | 2022-04-12 | 华人运通(江苏)技术有限公司 | System and method for improving small current test precision |
-
2015
- 2015-08-13 CN CN201520611739.6U patent/CN204925217U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106771476A (en) * | 2016-11-25 | 2017-05-31 | 西安微电子技术研究所 | A kind of high-tension current supervisory circuit |
| CN110486893A (en) * | 2019-08-30 | 2019-11-22 | 海信（山东）空调有限公司 | A kind of Defrost method and air conditioner of air conditioner |
| CN114325043A (en) * | 2021-12-16 | 2022-04-12 | 华人运通(江苏)技术有限公司 | System and method for improving small current test precision |
| CN114325043B (en) * | 2021-12-16 | 2023-10-17 | 华人运通(江苏)技术有限公司 | System and method for improving small current test precision |
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Effective date of registration: 20170622 Address after: 211102, 2 Nanjing, Jiangning economic and Technological Development Zone, Jiangsu, Patentee after: Nanjing Bo nale Electronic Technology Co. Ltd. Address before: 211100 No. 3128, printed Avenue, Jiangsu, Nanjing Patentee before: Nanjing Xie Chen Electronic Science and Technology Co., Ltd. |
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