阅读说明：本技术 一种固态电子开关专用集成控制器 (Special integrated controller for solid-state electronic switch ) 是由 李辉耀 于 2021-07-22 设计创作，主要内容包括：本发明涉及一种固态电子开关专用集成控制器,可适用于驱动VDMOS、Sic-MOSFET、GaN-MOSFET实现固态电子开关功能。芯片具备模拟量采集及隔离输出,数字信号隔离输入输出功能；可通过内总线接口实现参数配置,实现对限流控制、I～(2)t过流控制、立即跳闸保护、重复过载、保护动作自锁、缓开通慢关断几大功能的选通或组合使用。控制器包括内部供电电路、硬线指令输入接口电路、模拟量遥测隔离输出电路、数字量IO隔离控制电路、内总线接口电路、参数配置及使能控制电路、功能电路、驱动电路、输出接口电路。本发明解决了常规控制器功能简单、单一的缺陷,可实现角色重构、功能重构功能大大提高了固态电子开关的应用覆盖面。(The invention relates to a special integrated controller for a solid-state electronic switch, which is suitable for driving VDMOS, Sic-MOSFET and GaN-MOSFET to realize the function of the solid-state electronic switch. The chip has the functions of analog quantity acquisition, isolated output and digital signal isolated input and output; parameter configuration can be realized through an internal bus interface, and current limiting control and I are realized 2 t overcurrent control, immediate trip protection, repeated overload, self-locking of protection action, slow on and slow off, or combined use. The controller comprises an internal power supply circuit, a hard-wire instruction input interface circuit, an analog quantity telemetering isolation output circuit, a digital quantity IO isolation control circuit, an internal bus interface circuit, a parameter configuration and enabling control circuit, a functional circuit, a driving circuit and an output interface circuit. The invention overcomes the defects of simple and single function of the conventional controller, can realize role reconstruction and function reconstruction functions, and greatly improves the application coverage of the solid-state electronic switch.)

1. An integrated controller special for a solid-state electronic switch is characterized by comprising: the device comprises an internal power supply circuit, a hard-wire instruction input interface circuit, an analog quantity telemetering isolation output circuit, a digital quantity IO isolation control circuit, an internal bus interface circuit, a parameter configuration and enabling control circuit, a functional circuit, a driving circuit and an output interface circuit; the controlled object is a power MOSFET device;

the internal power supply circuit receives an input voltage provided by the outside, and the inside of the internal power supply circuit realizes DC-DC two-path isolation voltage through a transformer and provides the isolation voltage to the internal driving circuit, the functional circuit and the interface circuit;

the hard-line instruction input interface circuit realizes direct control on the drive circuit according to an externally input hard-line instruction control signal, thereby realizing on-off control on an external MOSFET;

the analog quantity telemetering isolation output circuit adopts a magnetic isolation mode, and realizes magnetic isolation output after modulating and demodulating current flowing between a drain electrode and a source electrode of a controlled object MOSFET and a path of externally acquired voltage analog quantity signal;

the digital quantity IO isolation control circuit realizes the isolation output control of four paths of digital signals, namely the switching state, the overcurrent protection state, the overvoltage protection state and the overtemperature protection state of an external controlled object MOSFET are transmitted to the internal bus interface circuit after being digitally isolated, and the external controller reads the information in real time in a serial bus mode according to a bus protocol; meanwhile, the digital IO isolation control circuit completes input isolation control of one path of ON/OFF switching instructions output from the internal bus interface circuit, and finally realizes ON-OFF control of an external controlled object MOSFET;

the parameter configuration and enabling control circuit receives an input signal from the internal bus interface circuit and completes parameter configuration and enabling control of the functional circuit according to a function agreed by a protocol;

the functional circuit comprises a protection circuit, a mode control circuit and a state monitoring circuit; the driving circuit is used for directly controlling an external MOSFET; the output interface circuit realizes the connection relation with the external MOSFET.

2. The integrated controller for solid-state electronic switch of claim 1, wherein: three pins including CFG and ON/T, OFF are reserved ON the integrated controller to be used as hard-wire instruction control, wherein the CFG is a hard-wire instruction input mode configuration pin, the ON/T, OFF is an ON/OFF instruction input pin, and the specific configuration mode is as follows:

TABLE 1 Command control mode

3. The integrated controller for solid-state electronic switch of claim 1, wherein: the hard-wired command has the highest priority control, and when the hard-wired command and the internal bus control command are received simultaneously, the drive circuit responds to the hard-wired command preferentially.

4. The integrated controller for solid-state electronic switch of claim 1, wherein: internal bus interface circuit, using I²The standard C serial interface mode is provided with a 1-way clock input pin SCL, a 1-way bidirectional data input and output pin SDA, a 1-way interrupt signal output pin and a 6-bit address programming control pin, and can realize the maximum 64-bit address addressing; the internal bus interface circuit realizes the input and output control of data through I²The C bus interface may be configured to 3 types of operating roles, namely solid state power controller, solid state current limiting switch, solid state relay.

5. The integrated controller for solid-state electronic switch of claim 1, wherein: the functional circuit comprises a protection circuit, a mode control circuit and a state monitoring circuit;

the protection circuit in the functional circuit comprises an overload protection circuit and a short-circuit protection circuit, wherein the overload protection circuit has two types of current limiting protection and overcurrent protection and is respectively composed of a current-limiting control circuit and an I²t is realized by a control circuit; the short-circuit protection circuit is realized by an immediate tripping circuit; turning off an external MOSFET after the protection time is up; through I²The bus interface realizes mode selection and related parameter configuration; the state monitoring circuit comprises a hard line INT indication and a bus state output, after protection action, on one hand, the state indication is output through an interrupt output pin INT, on the other hand, state information is written into a register corresponding to the functional circuit, and through I²The C-bus interface queries for this status.

6. The application specific integrated controller for solid state electronic switches of claim 5, wherein: the current-limiting protection adopts a closed-loop regulation mode, when the integrated controller is externally connected with a MOSFET (metal oxide semiconductor field effect transistor) for testing, when an external short circuit occurs, the closed-loop control inside the integrated controller is realized: the output current overshoot is less than 50A, the maximum current overshoot time does not exceed 5uS, the maximum current overshoot recovery time does not exceed 300uS, and the maximum input overshoot charge does not exceed 1 mC.

7. The application specific integrated controller for solid state electronic switches of claim 5, wherein: and when the external overload condition reaches a short-circuit protection point set by the short-circuit protection, the short-circuit protection circuit turns off the external MOSFET within the appointed short-circuit protection time, parameter configuration is realized through an I2C bus interface, an indication is given to an interrupt output pin INT after the protection action is executed, and the state can be inquired through an I2C bus interface.

8. The application specific integrated controller for solid state electronic switches of claim 5, wherein: the mode control circuit comprises a time delay turn-off control mode, a repeated overload control mode and a turn-back control mode.

9. The application specific integrated controller for solid state electronic switches of claim 8, wherein: selecting whether to start a repeated overload control mode through an I2C bus interface, and when the control mode is gated and the duration reaches a re-triggering time set value after overload protection is disconnected, automatically turning on the MOSFET again;

selecting whether to start a delayed turn-off control mode through an I2C bus interface, once the control mode is gated, starting timing from instruction turn-on, and when the turn-on time of the MOSFET reaches the set timing time, turning off the MOSFET;

whether a foldback control mode is started or not is selected through an I2C bus interface, when the control mode is gated, the MOSFET is not turned off after overload protection time is up, the MOSFET working mode is changed into a closed loop regulation mode, and the current is continuously kept according to the set foldback current limiting point.

10. The application specific integrated controller for solid state electronic switches of claim 8, wherein: the calculation formula of the foldback current limiting point is as follows:

wherein, V_DSThe voltage between the drain and the source of the MOSFET, Rsense is the resistance of the sampling resistor.

Technical Field

The invention relates to a special integrated control circuit for a solid-state electronic switch, belonging to the technical field of electronics.

Background

The solid-state electronic switch adopts a power tube as a core control switch, is widely applied to various fields at present, and has the advantages of no contact, no electric arc, no noise, quick response, small electromagnetic interference, long service life, high reliability and the like. From the protection characteristics, the solid-state electronic switch with the protection function and the solid-state electronic switch without the protection function are included. The solid-state electronic switch with protection function is mainly a solid-state relay, and the electronic switch with protection function mainly comprises a relay based on I²the solid-state power controller products with the t function and the short circuit immediate tripping function and the solid-state current limiting switch products based on the constant current limiting function.

The realization of the current solid-state electronic switch function and the drive control mode thereof is mainly classified into 2 types, the first type is a drive control circuit built by a separation circuit, and the second type is a drive control circuit realized by a special control chip, and the invention belongs to the second type of realization mode.

The first type of implementation is difficult to realize high-density integration and miniaturization due to the large number and variety of components. The existing second type of special controller has a single function, and can only realize partial functions of the solid-state electronic switch, such as a relay type special controller, a solid-state power controller type special controller, a solid-state current-limiting switch type special controller and the like, which cannot realize function reconstruction and role reconstruction, and the application range is greatly limited.

Disclosure of Invention

The technical problem solved by the invention is as follows: the defects of the prior art are overcome, a brand-new special integrated controller for the solid-state electronic switch is provided, the solid-state electronic switch realized by the chip design can avoid the defects that a circuit is complex, the types of devices are not beneficial to miniaturization and the like caused by adopting a separating device, and the defects that the application range is limited due to the fact that the traditional special controller is simple in function and single and cannot realize function reconstruction and role reconstruction can be avoided.

The technical scheme of the invention is as follows:

a solid state electronic switch application specific integrated controller comprising: the device comprises an internal power supply circuit, a hard-wire instruction input interface circuit, an analog quantity telemetering isolation output circuit, a digital quantity IO isolation control circuit, an internal bus interface circuit, a parameter configuration and enabling control circuit, a functional circuit, a driving circuit and an output interface circuit; the controlled object is a power MOSFET device;

the internal power supply circuit receives an input voltage provided by the outside, and the inside of the internal power supply circuit realizes DC-DC two-path isolation voltage through a transformer and provides the isolation voltage to the internal driving circuit, the functional circuit and the interface circuit;

the hard-line instruction input interface circuit realizes direct control on the drive circuit according to an externally input hard-line instruction control signal, thereby realizing on-off control on an external MOSFET;

the analog quantity telemetering isolation output circuit adopts a magnetic isolation mode, and realizes magnetic isolation output after modulating and demodulating current flowing between a drain electrode and a source electrode of a controlled object MOSFET and a path of externally acquired voltage analog quantity signal;

the digital quantity IO isolation control circuit realizes the isolation output control of four paths of digital signals, namely the switching state, the overcurrent protection state, the overvoltage protection state and the overtemperature protection state of an external controlled object MOSFET are transmitted to the internal bus interface circuit after being digitally isolated, and the external controller reads the information in real time in a serial bus mode according to a bus protocol; meanwhile, the digital IO isolation control circuit completes input isolation control of one path of ON/OFF switching instructions output from the internal bus interface circuit, and finally realizes ON-OFF control of an external controlled object MOSFET;

the parameter configuration and enabling control circuit receives an input signal from the internal bus interface circuit and completes parameter configuration and enabling control of the functional circuit according to a function agreed by a protocol;

the functional circuit comprises a protection circuit, a mode control circuit and a state monitoring circuit; the driving circuit is used for directly controlling an external MOSFET; the output interface circuit realizes the connection relation with the external MOSFET.

Furthermore, three pins including CFG and ON/T, OFF are reserved ON the integrated controller as a hard-wire command control, where CFG is a hard-wire command input mode configuration pin, and ON/T, OFF is an ON/off command input pin, and the specific configuration mode is as follows:

TABLE 1 Command control mode

Further, the hard-wired command has the highest priority control, and when the hard-wired command and the internal bus control command are received simultaneously, the drive circuit will respond to the hard-wired command preferentially.

Furthermore, the internal bus interface circuit adopts an I2C standard serial interface mode, and has a 1-way clock input pin SCL, a 1-way bidirectional data input and output pin SDA, a 1-way interrupt signal output pin and a 6-bit address programming control pin, so that the maximum 64-bit address addressing can be realized; the internal bus interface circuit realizes the input and output control of data, and can be configured into 3 types of working roles, namely a solid-state power controller, a solid-state current limiting switch and a solid-state relay, through an I2C bus interface.

Furthermore, the functional circuit comprises a protection circuit, a mode control circuit and a state monitoring circuit;

the protection circuit in the functional circuit comprises an overload protection circuit and a short-circuit protection circuit, wherein the overload protection circuit has two types of current limiting protection and overcurrent protection and is respectively composed of a current-limiting control circuit and an I²t is realized by a control circuit; the short-circuit protection circuit is realized by an immediate tripping circuit; turning off an external MOSFET after the protection time is up; through I²The bus interface realizes mode selection and related parameter configuration; the state monitoring circuit comprises a hard line INT indication and a bus state output, after protection action, on one hand, the state indication is output through an interrupt output pin INT, on the other hand, state information is written into a register corresponding to the functional circuit, and through I²The C-bus interface queries for this status.

Further, the current-limiting protection adopts a closed-loop regulation mode, when the integrated controller is externally connected with a MOSFET for testing, and when an extreme short circuit occurs outside, the closed-loop control inside the integrated controller is realized: the output current overshoot is less than 50A, the maximum current overshoot time does not exceed 5uS, the maximum current overshoot recovery time does not exceed 300uS, and the maximum input overshoot charge does not exceed 1 mC.

Further, when the external overload condition reaches the short-circuit protection point set by the short-circuit protection circuit, the short-circuit protection circuit turns off the external MOSFET within the appointed short-circuit protection time, parameter configuration is realized through the I2C bus interface, the interrupt output pin INT has an indication after the protection action is executed, and the state can be inquired through the I2C bus interface.

Furthermore, the mode control circuit comprises a time delay turn-off control mode, a repeated overload control mode and a turn-back control mode.

Further, whether a repeated overload control mode is started or not is selected through an I2C bus interface, and when the control mode is gated and the duration reaches a re-triggering time set value after overload protection is disconnected, the MOSFET automatically turns on again;

selecting whether to start a delayed turn-off control mode through an I2C bus interface, once the control mode is gated, starting timing from instruction turn-on, and when the turn-on time of the MOSFET reaches the set timing time, turning off the MOSFET;

whether a foldback control mode is started or not is selected through an I2C bus interface, when the control mode is gated, the MOSFET is not turned off after overload protection time is up, the MOSFET working mode is changed into a closed loop regulation mode, and the current is continuously kept according to the set foldback current limiting point.

Further, the calculation formula of the turning-back current-limiting point is as follows:

wherein, V_DSThe voltage between the drain and the source of the MOSFET, Rsense is the resistance of the sampling resistor.

Compared with the prior art, the invention has the advantages that:

(1) the driving circuit of the invention can pass through I²The bus realizes the adjustment of the driving current, can realize the adjustment of the turn-on and turn-off speed as required, can effectively restrain surge current and peak voltage caused by capacitive load and inductive load by setting the slow-switch function with different time lengths, improves the load carrying capacity of the power tube, improves the reliability and the service life of the power tube, ensures the safe, stable and reliable work of equipment, and can be flexibly set into a fast switch mode to meet the requirement of high-speed application.

(2) The power driving circuit can realize selection of MOSFET grid safety voltage through I2C bus configuration, can be compatible with drive control of VDMOS, Sic-MOSFET and GaN-MOSFET, and has wide application range;

(3) the power driving circuit can realize selection of MOSFET grid safety voltage through I2C bus configuration, can be compatible with drive control of VDMOS, Sic-MOSFET and GaN-MOSFET, has wide application range, and greatly reduces dependence on parasitic parameters of power tube devices;

(4) the invention can be configured into 3 types of work roles of solid-state power controller products, solid-state current limiter products and solid-state relay products through an I2C bus interface;

(5) the invention can configure 7 functions through an I2C bus interface, which not only can realize current limiting protection, overcurrent protection, short circuit protection, self-locking, repeated overload, foldback mode and timing, but also can realize any combination of the 7 functions, thereby greatly improving the application coverage of the solid-state electronic switch and leading the solid-state electronic switch to have the functions of realizing role reconstruction and function reconstruction.

Drawings

FIG. 1 is a schematic block diagram of the circuit of the present invention;

Detailed Description

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

The integrated controller chip has the functions of sampling the current of the MOSFET power loop, sampling the voltage of the load side and monitoring the over-temperature of the MOSFET; the power circuit isolation function is provided with instruction input, telemetering state output and a power circuit isolation function; the method realizes current limiting control and I by combining external parameter configuration and enable bits²And (3) gating or combining functions of t overcurrent control, immediate trip protection, protection action self-locking, slow switch-on and slow switch-off to realize function reconstruction and role reconstruction.

As shown in fig. 1, the integrated controller specially for a solid-state electronic switch of the present invention includes an internal power supply circuit 1, a hard-line instruction input interface circuit 2, an analog quantity telemetering isolation output circuit 3, a digital quantity IO isolation control circuit 4, an internal bus interface circuit 5, a parameter configuration and enable control circuit 6, a function circuit 7, a driving circuit 8, and an output interface circuit 9.

The controlled object is a power MOSFET device. The chip has the functions of sampling the current of the MOSFET power loop, sampling the voltage of the load side and monitoring the over-temperature of the MOSFET; the power circuit isolation function is provided with instruction input, telemetering state output and a power circuit isolation function; with configuration and control by external parametersThe mode of energy and position combination realizes the control of current limit and I²t overcurrent control, immediate trip protection, protection action self-locking, slow switch-on and slow switch-off or combined use.

The internal power supply circuit 1 receives an input voltage provided by the outside, and the inside realizes DC-DC 2-path isolation voltage through a transformer and provides the input voltage to an internal driving circuit, a functional circuit, an interface circuit and the like with +/-12V power supply voltage.

The hard-line instruction input interface circuit 2 realizes direct control of the drive circuit according to an externally input instruction control signal, so as to realize on-off control of an external MOSFET, the hard-line control has the highest priority control right, and when the hard-line instruction and the internal bus control instruction are received simultaneously, the drive circuit responds to the hard-line instruction preferentially. Reserving 3 pins in total of CFG and ON/T, OFF ON the chip as instruction control, wherein CFG is an instruction input mode configuration pin, and ON/T, OFF is an ON/OFF instruction input pin, and the specific configuration mode is as follows:

TABLE 1 Command control mode

The analog quantity telemetering isolation output circuit 3 adopts a magnetic isolation mode to modulate and demodulate the current flowing between the drain electrode and the source electrode of the controlled object MOSFET and a path of externally acquired voltage analog quantity signal to realize magnetic isolation output.

The digital quantity IO isolation control circuit 4 realizes the isolation output control of 4 paths of digital signals, namely the switching state, the overcurrent protection state, the overvoltage protection state and the overtemperature protection state of an external controlled object MOSFET are transmitted to the internal bus interface circuit after being digitally isolated, and an external controller can read the information in real time in a serial bus mode according to a bus protocol; meanwhile, the digital IO isolation control circuit completes input isolation control of one path of ON/OFF switching instructions output from the internal bus interface circuit, and finally realizes ON-OFF control of an external controlled object MOSFET.

The internal bus interface circuit 5 adopts an I2C standard serial interface mode, has a 1-way clock input pin SCL, a 1-way bidirectional data input and output pin SDA, a 1-way interrupt signal output pin and a 6-bit address programming control pin, and can realize the maximum 64-bit address addressing. The internal bus interface circuit mainly realizes the input and output control of data, and can be configured into 3 types of working roles through an I2C bus interface, namely a solid-state power controller, a solid-state current-limiting switch, a solid-state relay and a flexible combination of multiple functions.

The parameter configuration and enable control circuit 6 receives an input signal from the internal bus, completes the configuration of parameters and the enable control of the functional circuit according to the function agreed by the protocol, and finally completes the on-off control of the MOSFET, the selection and the control of the protection function and the mode in a matching way.

The function circuit comprises a protection circuit, a mode control circuit and a state monitoring circuit.

The protection circuit in the functional circuit comprises an overload protection circuit and a short-circuit protection circuit, wherein the overload protection circuit has two types of current limiting protection and overcurrent protection and is respectively composed of a current-limiting control circuit and an I²t is realized by a control circuit; the short-circuit protection circuit is realized by an immediate tripping circuit; turning off an external MOSFET after the protection time is up; through I²The bus interface realizes mode selection and related parameter configuration; the state monitoring circuit comprises a hard line INT indication and a bus state output, after protection action, on one hand, the state indication is output through an interrupt output pin INT, on the other hand, state information is written into a register corresponding to the functional circuit, and through I²The C-bus interface queries for this status.

The overcurrent protection characteristic curve satisfies the following formula:

wherein K and r are constants and take values shown in the following table 1, Ip is rated current multiplied by multiple (1.1-2.5), M is configuration parameter value of 0.001-0.05, and I is current telemetering.

TABLE 2, K, r value-taking table

	K	r
			General inverse time limit	0.14	0.02
Very inverse time limit	13.5	1
			Extreme inverse time limit	80	2

Current-limiting protection adopts closed-loop regulation mode, and when the external MOSFET test of chip, when extreme short circuit appears in the outside, the closed-loop control of chip inside can realize:

1) the output current overshoot is less than 50A;

2) the maximum current overshoot time does not exceed 5 uS;

3) the maximum value of the current overshoot recovery time does not exceed 300 uS;

4) the maximum value of input overshoot charge does not exceed 1 mC;

the short-circuit protection is that when the external overload condition reaches a short-circuit protection point set by the short-circuit protection, the short-circuit protection switches off the external MOSFET within the appointed short-circuit protection time, parameter configuration is realized through an I2C bus interface, an interrupt output pin INT has an indication after the protection action is executed, and the state can be inquired through an I2C bus interface;

the mode control circuit mainly comprises a time delay turn-off control mode, a repeated overload control mode and a turn-back control mode.

1. Whether to start the repeated overload function can be selected through an I2C bus interface, and when the function is gated and the duration reaches the re-triggering time set value after the overload protection is disconnected, the MOSFET is automatically turned on again;

2. whether the delayed turn-off function is started or not can be selected through the I2C bus interface, once the function is turned on, the function is started to be timed from the command turn-on, and when the turn-on time of the MOSFET reaches the set timing time, the MOSFET is turned off;

3. the I2C bus interface can select whether to start the foldback mode, when the function is gated, the MOSFET is not turned off after the overload protection time, the MOSFET working mode is changed into a closed loop regulation mode, and the current set according to the foldback current limiting point is continuously kept. The calculation formula of the foldback current limiting point is as follows:

wherein, V_DSThe voltage between the drain and the source of the MOSFET, Rsense is the resistance of the sampling resistor.

The power driving circuit can realize selection of MOSFET grid safety voltage through I2C bus configuration, can be compatible with drive control of VDMOS, Sic-MOSFET and GaN-MOSFET, has wide application range and greatly reduces dependence on parasitic parameters of power tube devices.

The driving circuit 8 is used for directly controlling an MOSFET outside the chip, the MOSFET driving output is in a current source output mode, the setting of driving current can be realized through an I2C bus interface, and the driving of a VDMOS, a Sic-MOSFET and a GaN-MOSFET can be realized; a VG pin is reserved on the chip and is used as an external MOSFET grid input end;

the power driving circuit realizes selection of MOSFET grid safety voltage through I2C bus configuration, the grid clamping voltage Vgs of MOSFET driving output has two voltage systems which can be selected, the voltage range of the voltage system 1 is + 11V- +15V, and the driving of VDMOS and Sic-MOSFET can be realized; the voltage range of the voltage system 2 is + 4V- +5V, and the GaN-MOSFET can be driven. Can be compatible with the drive control of VDMOS, Sic-MOSFET and GaN-MOSFET at the same time, and has wide application range.

The output interface circuit is mainly realized in the connection relation of circuits such as an external MOSFET, and Vd, Vg, Ins +, Ins-, Tms +, Tms-, Temp + and Temp-pins are reserved on a chip. The device is used for realizing MOSFET control, external temperature signal input, external voltage signal output and external current signal input.

The driving circuit can realize the adjustment of driving current through an I2C bus, can realize the adjustment of the turn-on and turn-off speed according to the needs, can effectively restrain surge current and peak voltage caused by capacitive load and inductive load by setting slow-switch function with different time lengths, improves the loading capacity of the power tube, improves the reliability and the service life of the power tube, ensures the safe, stable and reliable work of equipment, can be flexibly set into a fast switch mode, and meets the needs of high-speed application.

Those skilled in the art will appreciate that those matters not described in detail in the present specification are well known in the art.