CN117394660A - Switching tube driving circuit with reverse connection protection function - Google Patents

Switching tube driving circuit with reverse connection protection function Download PDF

Info

Publication number
CN117394660A
CN117394660A CN202311167902.XA CN202311167902A CN117394660A CN 117394660 A CN117394660 A CN 117394660A CN 202311167902 A CN202311167902 A CN 202311167902A CN 117394660 A CN117394660 A CN 117394660A
Authority
CN
China
Prior art keywords
switching tube
resistor
reverse connection
connection protection
driving 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
Application number
CN202311167902.XA
Other languages
Chinese (zh)
Inventor
孙彪
丁万新
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Chuantu Microelectronics Co ltd
Original Assignee
Shanghai Chuantu Microelectronics Co ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Shanghai Chuantu Microelectronics Co ltd filed Critical Shanghai Chuantu Microelectronics Co ltd
Priority to CN202311167902.XA priority Critical patent/CN117394660A/en
Publication of CN117394660A publication Critical patent/CN117394660A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/08—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H11/00—Emergency protective circuit arrangements for preventing the switching-on in case an undesired electric working condition might result
    • H02H11/002—Emergency protective circuit arrangements for preventing the switching-on in case an undesired electric working condition might result in case of inverted polarity or connection; with switching for obtaining correct connection

Abstract

The application provides a switching tube driving circuit with reverse connection protection function, and relates to the technical field of integrated circuits. The switching tube driving circuit with the reverse connection protection function comprises a forward driving unit and a reverse protection unit; the forward driving unit comprises a switching tube and a charging current source, wherein the charging current source is connected with the switching tube and is used for controlling the switching tube to be conducted when a power supply is connected positively; the reverse protection unit is connected with the forward driving unit and is used for controlling the switching tube to be conducted when the power supply is reversely connected. According to the switching tube gate voltage switching device, under the condition that the power supply voltage is reversely connected, the switching tube gate can be charged, the channel of the switching tube gate voltage switching device is conducted, heat loss is reduced, and the switching tube is prevented from being damaged by heat.

Description

Switching tube driving circuit with reverse connection protection function
Technical Field
The application relates to the technical field of integrated circuits, in particular to a switching tube driving circuit with a reverse connection protection function.
Background
MOSFETs (Metal Oxide Semiconductor Field Effect Transistor, metal oxide semiconductor type field effect transistors) are a common device in integrated circuits, often used as switching transistors. The prior art switching tube driving circuit is shown in fig. 1, and the circuit includes a switching tube M0, parasitic capacitances Cgs and Cgd thereof, a body diode D0, a zener diode D1, a resistor R1, a charging current source MP, and a charge pump stabilizing capacitor C1. Wherein VS is the system supply voltage, VS+VCP is the charge pump voltage, VBAT is the power supply, and RL is the load resistor.
As shown in fig. 1, when the power supply VBAT is being connected, the charging current source MP is turned on to charge the gate capacitances Cgs, cgd of the switching transistor M0. While current also flows through resistor R1, resistor R2 and zener diode D1. The zener diode D1 protects the gate-source voltage vgs of the switching tube M0, which does not exceed the zener reverse-turn-on voltage of the zener diode D1. The charge pump increases the supply voltage VS by a voltage VCP so that the charging current source MP can drive the gate voltage of the switching transistor M0 up to vs+vcp. Thereby ensuring that the switching tube M0 can be sufficiently turned on. When the switching tube M0 is fully turned on, the OUT voltage approaches VS due to the small on-resistance of the switching tube M0.
As shown in fig. 1, gnd=vbat, vs=0 when the power supply VBAT is reversely connected. The body diode D0 of the switching tube M0 is turned on, and the current path is: GND goes to load resistor RL, to body diode D0, to VS. In this case, the voltage drop vd0=0.7v across the body diode D0, the current flowing id0= (VS-0.7)/RL, the power pd0=vd0×id0=0.7×0.7 (VS-0.7)/RL. The gate voltage vgate=vd0=0.7v, which is less than the threshold voltage at which the channel of the switching transistor M0 is turned on, and the channel of the switching transistor M0 is not turned on.
The inventor found that, when implementing the present invention, in the switching tube driving circuit of the prior art, under the condition that the power supply VBAT is reversely connected, the voltage across the switching tube M0 is the voltage drop vd0=0.7v across the body diode D0, the flowing current id0= (VS-0.7)/RL, the power pd0=vd0×id0=0.7×0.7 (VS-0.7)/RL, and the heat is much. If the power supply VBAT is connected reversely for a long time, the switching tube M0 may be damaged thermally.
Disclosure of Invention
In view of this, the embodiments of the present disclosure provide a switching tube driving circuit with reverse connection protection function, which solves the defect of thermal damage of the switching tube caused by reverse connection of the power supply VBAT in the prior art.
The embodiment of the specification provides the following technical scheme:
the switching tube driving circuit with the reverse connection protection function comprises a forward driving unit and a reverse protection unit; the forward driving unit comprises a switching tube and a charging current source, wherein the charging current source is connected with the switching tube and is used for controlling the switching tube to be conducted when a power supply is connected positively; the reverse protection unit is connected with the forward driving unit and is used for controlling the switching tube to be conducted when the power supply is reversely connected.
In some embodiments, the reverse protection unit includes a second resistor (R2), one end of the second resistor (R2) is connected to the gate of the switching tube, and the other end is grounded.
In some embodiments, the second resistor (R2) has a resistance value in the megaohm range, and the current flowing through the second resistor (R2) has a current value in the microampere range.
In some embodiments, the reverse protection unit further comprises a first resistor (R1) and a first diode (D1); the first resistor (R1) and the first diode (D1) are connected in parallel between the grid electrode and the source electrode of the switching tube, the positive electrode of the first diode (D1) is connected with the grid electrode of the switching tube, and the negative electrode of the first diode is connected with the source electrode of the switching tube.
In some embodiments, the forward driving unit multiplexes the first resistor (R1) and the first diode (D1) with the reverse protection unit.
In some embodiments, the reverse protection unit further comprises a second diode (D2); the positive electrode of the second diode (D2) is connected with the positive electrode of the system power supply, and the negative electrode of the second diode is connected with the positive electrode of the charge pump power supply.
In some embodiments, the charging current source is connected to the gate of the switching tube, and is used for charging the gate of the switching tube, so that the switching tube is turned on in a forward direction.
In some embodiments, the second resistor (R2) is an adjustable resistor for controlling the conduction speed of the switching tube.
In some embodiments, when the reverse power supply voltage is fixed, the smaller the sum of the resistance values of the first resistor (R1) and the second resistor (R2), the faster the conduction speed; when the sum of the resistance values of the first resistor (R1) and the second resistor (R2) is fixed, the larger the reverse power supply voltage is, the faster the conduction speed is.
In some embodiments, the conduction speed is on the order of microseconds.
Compared with the prior art, the beneficial effects that above-mentioned at least one technical scheme that this description embodiment adopted can reach include at least: (1) under the condition that the power supply is connected positively, the reverse protection unit does not work, and normal work application is not affected; (2) under the condition of reverse connection of power supply voltage, the GATE electrode of the switching tube can be charged, so that the channel of the switching tube is conducted, heat loss is reduced, and the thermal damage of the switching tube is prevented; (3) the power supply VBAT is reversely connected under the condition of high voltage, the reverse protection unit can protect the switching tube with the voltage withstand of 5V of the gate-source voltage VGS of the switching tube, at the moment, the diodes D1 and D2 are conducted, and the gate-source voltage VGS of the switching tube M0 is ensured not to be over-voltage; (4) fewer devices are added, and the area is saved; (5) the reverse conduction speed is high and can be controlled to be in the microsecond level.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a prior art switching tube drive circuit;
fig. 2 is a schematic diagram of a switching tube driving circuit with reverse connection protection function according to an embodiment of the present application;
FIG. 3 is a schematic diagram illustrating a current flow of the driving circuit shown in FIG. 2 when the power supply is turned on;
fig. 4 is a circuit schematic without using the second diode D2.
Detailed Description
Embodiments of the present application are described in detail below with reference to the accompanying drawings.
Other advantages and effects of the present application will become apparent to those skilled in the art from the present disclosure, when the following description of the embodiments is taken in conjunction with the accompanying drawings. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. The present application may be embodied or carried out in other specific embodiments, and the details of the present application may be modified or changed from various points of view and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.
It is noted that various aspects of the embodiments are described below within the scope of the following claims. It should be apparent that the aspects described herein may be embodied in a wide variety of forms and that any specific structure and/or function described herein is merely illustrative. Based on the present application, one skilled in the art will appreciate that one aspect described herein may be implemented independently of any other aspect, and that two or more of these aspects may be combined in various ways. For example, apparatus may be implemented and/or methods practiced using any number and aspects set forth herein. In addition, such apparatus may be implemented and/or such methods practiced using other structure and/or functionality in addition to one or more of the aspects set forth herein.
It should also be noted that the illustrations provided in the following embodiments merely illustrate the basic concepts of the application by way of illustration, and only the components related to the application are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complicated.
In addition, in the following description, specific details are provided in order to provide a thorough understanding of the examples. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details.
The switching tube driving circuit with the reverse connection protection function comprises a forward driving unit and a reverse protection unit; the forward driving unit comprises a switching tube and a charging current source, wherein the charging current source is connected with the switching tube and is used for controlling the switching tube to be conducted when a power supply is connected positively; the reverse protection unit is connected with the forward driving unit and is used for controlling the switching tube to be conducted when the power supply is reversely connected. The charging current source is connected with the grid electrode of the switching tube and is used for charging the grid electrode of the switching tube, so that the switching tube is conducted in the forward direction.
In some embodiments, as shown in fig. 2, the forward driving unit is the same as the switching tube driving circuit shown in fig. 1, and the reverse protection unit includes a first resistor R1, a second resistor R2, a first diode D1, and a second diode D2; the first resistor R1 and the first diode D1 are connected in parallel between the grid electrode and the source electrode of the switching tube, the positive electrode of the first diode D1 is connected with the grid electrode of the switching tube, and the negative electrode of the first diode D1 is connected with the source electrode of the switching tube; one end of the second resistor R2 is connected with the grid electrode of the switching tube, and the other end of the second resistor R2 is grounded; the positive pole of the second diode D2 is connected with the positive pole of the system power supply, and the negative pole of the second diode D2 is connected with the positive pole of the charge pump power supply. The forward driving unit and the reverse protection unit multiplex the first resistor R1 and the first diode D1, and the first diode D1 biases the grid electrode of the switching tube M0 when providing power supply forward connection; the resistance value of the second resistor R2 is in the megaohm level, and the current value flowing through the second resistor R2 is in the microampere level. The second diode D2 biases the gate of the switching tube M0 when the power supply is connected reversely, and can be used as a charge pump voltage regulator during normal operation.
In this embodiment, the current flow of the driving circuit when the power supply is connected reversely is shown in fig. 3. Referring to fig. 3, when the power supply VBAT is reversely connected, the body diode D0 of the switching transistor M0 is first turned on, vout=vd0=0.7v, and a current id0_start= (VS-0.7)/RL flows. At the same time, a current flows from GND through the second resistor R2 to charge the GATE of the switching transistor M0, i.e., to charge the parasitic capacitances Cgs and Cgd of the switching transistor M0. When the gate voltage VGATE of the switching transistor M0 is greater than the turn-on threshold VTH, the channel of the switching transistor M0 starts to turn on. When the gate voltage VGATE is charged to the channel current ids=id0_start of the switching transistor M0, the body diode D0 is no longer powered down, the VOUT voltage drops to less than 0.7V, and at this time, the miller stage is entered, VOUT continuously drops, and the gate voltage VGATE is almost unchanged. When VOUT continues to drop until the switching transistor M0 enters the linear region, the miller plateau ends, and the gate voltage VGATE is eventually charged up to the zener diode clamping voltage, at which time RDSON of the switching transistor M0 is minimum, the zener diodes D1, D2 are turned on, and ir2=id1+id2+ir1. After the channel of the switching tube M0 is fully turned on, the current ids=vs/RL flows, the voltage vds=id0×rdson at the two ends, the power pd0=vds=ids= (VS/RL)/(2×rdson), and the heat generation is small. When the power supply VBAT is connected, the second resistor R2 is generally set at the mΩ level, so that the microampere current is applied without affecting the gate voltage VGATE of the switching tube M0, and the diodes D1 and D2 are not powered.
Further, the second resistor R2 is an adjustable resistor, and is used for controlling the conducting speed of the switching tube M0. When the switching tube M0 is turned on reversely, the charging current i=vbat/(r1+r2) to the gate of the switching tube M0 is higher, and the conduction speed is faster. Therefore, when the reverse power supply voltage VGATE is fixed, the smaller the sum of the resistance values r1+r2 of the first resistor R1 and the second resistor R2 is, the faster the conduction speed is; when the sum of the resistance values r1+r2 of the first resistor R1 and the second resistor R2 is fixed, the larger the reverse power supply voltage VGATE is, the faster the conduction speed is. Wherein the conduction speed is typically on the order of microseconds.
In some embodiments, as shown in fig. 4, the present embodiment is different from the previous embodiment in that the second diode D2 is not used. In this embodiment, the forward driving unit is the same as the switching tube driving circuit shown in fig. 1, and the reverse protection unit includes a second resistor R2 and multiplexes a first resistor R1 and a first diode D1 with the forward driving unit; the first resistor R1 and the first diode D1 are connected in parallel between the grid electrode and the source electrode of the switching tube M0, the positive electrode of the first diode D1 is connected with the grid electrode of the switching tube M0, and the negative electrode of the first diode D1 is connected with the source electrode of the switching tube M0; one end of the second resistor R2 is connected with the grid electrode of the switching tube M0, and the other end of the second resistor R is grounded. The first diode D1 biases the grid electrode of the switching tube M0 when the power supply is connected positively; the resistance value of the second resistor R2 is in the megaohm level, and the current value flowing through the second resistor R2 is in the microampere level.
Further, in the embodiment, the second resistor R2 is an adjustable resistor for controlling the conducting speed of the switching tube M0. When the switching tube M0 is turned on reversely, the charging current i=vbat/(r1+r2) to the gate of the switching tube M0 is higher, and the conduction speed is faster. Therefore, when the reverse power supply voltage VGATE is fixed, the smaller the sum of the resistance values r1+r2 of the first resistor R1 and the second resistor R2 is, the faster the conduction speed is; when the sum of the resistance values r1+r2 of the first resistor R1 and the second resistor R2 is fixed, the larger the reverse power supply voltage VGATE is, the faster the conduction speed is. Wherein the conduction speed is typically on the order of microseconds.
According to the embodiment of the application, the characteristic that the RDSON of the linear region of the switching tube M0 is small is utilized, when the power supply VBAT is reversely connected, the channel of the switching tube M0 can be opened, so that current can flow from the channel of the switching tube M0 instead of the body diode D0, the voltage drop on the switching tube M0 is reduced, the heat loss is reduced, the problems that the traditional driving circuit is overlarge in heating and easy to burn when the power supply is reversely connected are solved, the fault tolerance of a system board is improved, and the application scene is expanded. In addition, the resistor is added, the original zener diode of the switching tube is multiplexed, the effect of supplying power to the grid GATE of the switching tube M0 when the power supply is connected reversely is achieved, the grid source voltage VGS is protected from overvoltage when the power supply is connected reversely, an additional large-area driving tube is not needed to be added, and the area is saved. In addition, the embodiment of the application can control the conducting speed of the switching tube M0 when the power supply is reversely connected by adjusting the size of the second resistor R2, and the resistor design ensures that the circuit has no initialization problem.
In this specification, identical and similar parts of the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. Meanwhile, the specification uses specific words to describe the embodiments of the specification. Reference to "one embodiment," "an embodiment," and/or "some embodiments" means that a particular feature, structure, or characteristic is associated with at least one embodiment of the present description. Thus, it should be emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various positions in this specification are not necessarily referring to the same embodiment. Furthermore, certain features, structures, or characteristics of one or more embodiments of the present description may be combined as suitable.
Furthermore, the order in which the elements and sequences are processed, the use of numerical letters, or other designations in the description are not intended to limit the order in which the processes and methods of the description are performed unless explicitly recited in the claims. While certain presently useful inventive embodiments have been discussed in the foregoing disclosure, by way of various examples, it is to be understood that such details are merely illustrative and that the appended claims are not limited to the disclosed embodiments, but, on the contrary, are intended to cover all modifications and equivalent arrangements included within the spirit and scope of the embodiments of the present disclosure. For example, while the system components described above may be implemented by hardware devices, they may also be implemented solely by software solutions, such as installing the described system on an existing processing device or mobile device.
While the basic concepts have been described above, it will be apparent to those skilled in the art that the foregoing detailed disclosure is by way of example only and is not intended to be limiting. Although not explicitly described herein, various modifications, improvements, and adaptations to the present disclosure may occur to one skilled in the art. Such modifications, improvements, and modifications are intended to be suggested within this specification, and therefore, such modifications, improvements, and modifications are intended to be included within the spirit and scope of the exemplary embodiments of the present invention.

Claims (10)

1. The switching tube driving circuit with the reverse connection protection function is characterized by comprising a forward driving unit and a reverse protection unit; the forward driving unit comprises a switching tube and a charging current source, wherein the charging current source is connected with the switching tube and is used for controlling the switching tube to be conducted when a power supply is connected positively; the reverse protection unit is connected with the forward driving unit and is used for controlling the switching tube to be conducted when the power supply is reversely connected.
2. The switching tube driving circuit with the reverse connection protection function according to claim 1, wherein the reverse connection protection unit comprises a second resistor (R2), one end of the second resistor (R2) is connected with the gate of the switching tube, and the other end of the second resistor is grounded.
3. The switching tube driving circuit with reverse connection protection function according to claim 2, wherein the resistance value of the second resistor (R2) is in the megaohm level, and the current value flowing through the second resistor (R2) is in the microampere level.
4. The switching tube driving circuit with reverse connection protection function according to claim 2, wherein the reverse connection protection unit further comprises a first resistor (R1) and a first diode (D1); the first resistor (R1) and the first diode (D1) are connected in parallel between the grid electrode and the source electrode of the switching tube, the positive electrode of the first diode (D1) is connected with the grid electrode of the switching tube, and the negative electrode of the first diode is connected with the source electrode of the switching tube.
5. The switching tube driving circuit with reverse connection protection function according to claim 4, wherein the forward driving unit multiplexes the first resistor (R1) and the first diode (D1) with the reverse connection protection unit.
6. Switching tube driving circuit with reverse connection protection function according to claim 2, characterized in that the reverse connection protection unit further comprises a second diode (D2); the positive electrode of the second diode (D2) is connected with the positive electrode of the system power supply, and the negative electrode of the second diode is connected with the positive electrode of the charge pump power supply.
7. The switching tube driving circuit with reverse connection protection function according to claim 1, wherein the charging current source is connected to the gate of the switching tube and is used for charging the gate of the switching tube, so that the switching tube is turned on in a forward direction.
8. Switching tube driving circuit with reverse connection protection according to any of claims 2 to 7, characterized in that the second resistor (R2) is an adjustable resistor for controlling the conduction speed of the switching tube.
9. The switching tube driving circuit with reverse connection protection function according to claim 8, wherein when the reverse connection power supply voltage is fixed, the smaller the sum of the resistance values of the first resistor (R1) and the second resistor (R2) is, the faster the conduction speed is; when the sum of the resistance values of the first resistor (R1) and the second resistor (R2) is fixed, the larger the reverse power supply voltage is, the faster the conduction speed is.
10. The switching tube driving circuit with reverse connection protection function according to claim 9, wherein the on speed is in the order of microseconds.
CN202311167902.XA 2023-09-11 2023-09-11 Switching tube driving circuit with reverse connection protection function Pending CN117394660A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202311167902.XA CN117394660A (en) 2023-09-11 2023-09-11 Switching tube driving circuit with reverse connection protection function

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202311167902.XA CN117394660A (en) 2023-09-11 2023-09-11 Switching tube driving circuit with reverse connection protection function

Publications (1)

Publication Number Publication Date
CN117394660A true CN117394660A (en) 2024-01-12

Family

ID=89439920

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202311167902.XA Pending CN117394660A (en) 2023-09-11 2023-09-11 Switching tube driving circuit with reverse connection protection function

Country Status (1)

Country Link
CN (1) CN117394660A (en)

Similar Documents

Publication Publication Date Title
JP4031539B2 (en) Device including load protection circuit against excessive input voltage and load protection method against excessive input voltage
US8054106B2 (en) Load driving device
US6043965A (en) Low loss reverse battery protection
US8289669B2 (en) Semiconductor device including over voltage protection circuit having gate discharge circuit operated based on temperature and voltage as to output transistor
US9520789B2 (en) Power supply device
CN101588062B (en) Protection circuit for semiconductor integrated circuit, driving method and system therefor
US8270133B2 (en) Power supply control apparatus
US20120262220A1 (en) Cascode switches including normally-off and normally-on devices and circuits comprising the switches
US8299841B2 (en) Semiconductor device
US9755548B2 (en) Bootstrap compensation circuit and power module
KR20070056053A (en) A semiconductor switch arrangement and an electronic device
US8040647B2 (en) System and method for protection against loss of battery in reverse battery protected devices
JP2013251671A (en) Semiconductor device
EP4106162A1 (en) Driving circuit of power switching device, and driving system
CN104104225A (en) Regulator circuit and integrated circuit device forming the regulator circuit
CN110855277A (en) Adjustable clamping circuit
GB2553588A (en) Multi-semiconductor solid state power controllers and method for managing inductive switching transients thereof
US20170110876A1 (en) Bidirectional current limiter
JP7232208B2 (en) semiconductor equipment
CN105991052B (en) Rectifier circuit with reduced reverse recovery time
CN117394660A (en) Switching tube driving circuit with reverse connection protection function
CN108512191B (en) Surge protection circuit, electronic equipment and surge protection method of circuit
CN110176856B (en) Zero-quiescent-current power switch circuit with overcurrent protection and implementation method
CN109524944B (en) Protection circuit of direct current fan driver
CN107977035B (en) Gate driver circuit, operating method thereof and system for circuit protection

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
CB02 Change of applicant information
CB02 Change of applicant information

Address after: Room 401, 4th Floor, Building 18, No. 599 Gaojing Road, Xujing Town, Qingpu District, Shanghai, 201702, and Room 501, 5th Floor

Applicant after: Shanghai chuantu Microelectronics Co.,Ltd.

Address before: No.888, Huanhu West 2nd Road, Lingang New District, China (Shanghai) pilot Free Trade Zone, Pudong New Area, Shanghai, 201306

Applicant before: Shanghai chuantu Microelectronics Co.,Ltd.