MCU simulation debugger with high-voltage isolation protection

Abstract

The utility model relates to an MCU simulation debugger with high-voltage isolation protection. The MCU simulation debugger comprises a USB power supply communication circuit module, a first DC step-down circuit, a DC-DC power isolation module, a second DC step-down circuit, a main control chip minimum system, a burning code external storage FLASH control circuit, an off-line burning BURN key detection circuit, a JTAG simulation / IIC burning interface isolation module and a three-section dial switch. A dial switch state detection module; and a machine burning control interface. The JTAG simulation / IIC burning interface isolation module realizes 1500Vrms electrical isolation of a debugging board card and simulator equipment, online simulation debugging of resistance product firmware can be realized, and a software developer does not need to care about the electrical isolation condition of the debugging board card and only needs to concentrate on debugging codes; multi-interface and multi-level high-speed simulation and burning are supported, level switching of a debugging board card is rapidly achieved through a dial-up gear, and the level compatibility of the simulator is improved.

Description

Technical Field

[0001] The present application relates to the technical field of simulation debuggers, and in particular to an MCU simulation debugger with high-voltage isolation protection. Background Art

[0002] At present, the MCU simulation debuggers on the market generally do not have isolation protection for the simulation debugging and burning download signal interfaces. Due to cost constraints, when the 220VAC household appliances designed by the customer are powered by a non-isolated switching power supply, there will be a problem that the signal ground is a hot ground instead of a cold ground. If the debugger does not take corresponding electrical isolation measures at this time and performs online simulation debugging, it will cause the household appliance debugging board or debugger to "explode". Therefore, developers can only download the debugging board program by disconnecting the power supply of the debugging board, and then unplug the simulator and connect it to the mains for functional verification. The simulation debugging function under the mains cannot be realized, which greatly hinders the software development progress of the customer's home appliance products, and at the same time brings certain cost losses. The present utility model proposes a new, safe and effective solution to the above-mentioned risk problems. Utility Model Content

[0003] Based on this, it is necessary to provide an MCU simulation debugger with high-voltage isolation protection to address the above technical problems.

[0004] The invention discloses an MCU simulation debugger with high-voltage isolation protection, comprising: a USB power supply and communication circuit module, a first DC step-down circuit, a DC-DC power isolation module, a second DC step-down circuit, a minimum system of a main control chip, a FLASH control circuit for external storage of burning code, a BURN button detection circuit for offline burning, a JTAG simulation / IIC burning interface isolation module, a three-stage DIP switch, a DIP switch status detection module, and a machine burning control interface.

[0005] The first output end of the USB power supply and communication circuit module is connected to the input end of the first DC step-down circuit, and the output end of the first DC step-down circuit is connected to the power end of the minimum system of the main control chip; the output end of the first DC step-down circuit is connected to the input power end of the JTAG simulation / IIC burning interface isolation module.

[0006] The second output end of the USB power supply and communication circuit module is connected to the DC-DC power supply isolation module, the first output end of the DC-DC power supply isolation module is connected to the second DC step-down circuit, the output end of the second DC step-down circuit is connected to the first input end of the three-stage dip switch, the second output end of the DC-DC power supply isolation module is connected to the second input end of the three-stage dip switch, the output end of the three-stage dip switch is connected to the output power end VCC2 of the JTAG simulation / IIC burning interface isolation module; the three-stage dip switch is connected to the dip switch status detection module.

[0007] The grounds of the USB power supply and communication circuit module, the first DC step-down circuit, the main control chip minimum system, and the input end of the DC-DC power supply isolation module are all connected to the input ground. The grounds of the output end of the DC-DC power supply isolation module, the second DC step-down circuit, the three-stage dip switch, and the output end of the JTAG simulation / IIC burning interface isolation module are all connected to the isolation ground.

[0008] The external storage FLASH control circuit for burning code, the offline burning BURN button detection circuit, the JTAG simulation / IIC burning interface isolation module, the DIP switch status detection module and the machine burning control interface are all connected to the minimum system of the main control chip.

[0009] In one embodiment, the DC-DC power isolation module includes: two first filter capacitors, two second filter capacitors and an isolated voltage-stabilized power supply module.

[0010] The first output end of the USB power supply and communication circuit module is connected to the voltage input end of the isolated voltage-stabilized power supply module, and the GND end of the isolated voltage-stabilized power supply module is connected to the input ground; the first first filter capacitor and the second second filter capacitor are both connected in parallel between the voltage input end and the GND end of the isolated voltage-stabilized power supply module.

[0011] The positive output terminal of the isolated voltage-stabilized power supply module is used to output the isolated voltage; the negative output terminal of the isolated voltage-stabilized power supply module is connected to the isolation ground; the second first filter capacitor and the second second filter capacitor are both connected in parallel between the positive output terminal and the negative output terminal of the isolated voltage-stabilized power supply module; the positive output terminal of the isolated voltage-stabilized power supply module is connected to the second input terminal of the three-stage dip switch, the output terminal of the three-stage dip switch is connected to the output power terminal VCC2 of the JTAG simulation / IIC burning interface isolation module, and the three-stage dip switch, the output terminal of the JTAG simulation / IIC burning interface isolation module, and the output terminal of the isolated voltage-stabilized power supply module are grounded in common.

[0012] In one embodiment, the isolated voltage-stabilized power supply module is an isolated voltage-stabilized power supply module that inputs a 5V DC voltage and outputs a 5V DC voltage.

[0013] In one embodiment, the second DC step-down circuit includes two directional filter capacitors, three third filter capacitors, one fourth filter capacitor, and a voltage stabilizing and step-down module.

[0014] The input end of the voltage stabilizing and step-down module is connected to the output end of the DC-DC power supply isolation module, the positive end of the first directional filter capacitor and one end of the first third filter capacitor are both connected to the input end of the voltage stabilizing and step-down module, the negative end of the first directional filter capacitor and the other end of the first third filter capacitor are both connected to the GND end of the voltage stabilizing and step-down module, and the GND end of the voltage stabilizing and step-down module is connected to the isolation ground.

[0015] The positive end of the second directional filter capacitor, one end of the fourth filter capacitor, one end of the second third filter capacitor and one end of the third third filter capacitor are all connected to the output end of the voltage stabilizing and step-down module, and the output end of the voltage stabilizing and step-down module outputs a 3.3V voltage. The negative end of the second directional filter capacitor, the other end of the fourth filter capacitor, the other end of the second third filter capacitor and the other end of the third third filter capacitor are all connected to the GND end of the voltage stabilizing and step-down module.

[0016] The output end of the voltage regulator and step-down module is connected to the second input end of the three-stage dip switch, and the output end of the three-stage dip switch is connected to the output power supply end VCC2 of the JTAG simulation / IIC burning interface isolation module.

[0017] The output ends of the voltage regulator and step-down module, three-stage DIP switch, and JTAG simulation / IIC burning interface isolation module share a common ground.

[0018] In one embodiment, the voltage regulator and buck module is a forward low-dropout voltage regulator with an output voltage of 3.3V.

[0019] In one embodiment, the JTAG emulation / IIC programming interface isolation module includes two isolation channels with the same structure.

[0020] The isolation channel includes: input filter capacitor, four series matching resistors, bidirectional isolator ISO1640, output filter capacitor, and four pull-up resistors.

[0021] The SDA1 and SCL1 terminals of the bidirectional isolator ISO1640 are connected to the minimum system of the main control chip through a first series matching resistor and a second series matching resistor, respectively. One end of the first pull-up resistor, one end of the second pull-up resistor, one end of the input filter capacitor, and the input power supply VDD1 of the bidirectional isolator ISO1640 are all connected to the output end of the first DC step-down circuit. The other ends of the first pull-up resistor and the second pull-up resistor are respectively connected to the SCL1 and SDA1 terminals of the bidirectional isolator ISO1640. The other end of the input filter capacitor and the GND1 terminal of the bidirectional isolator ISO1640 are both connected to the GND terminal of the first DC step-down circuit.

[0022] The SDA2 and SCL2 terminals of the bidirectional isolator ISO1640 are connected to the minimum system of the main control chip through a third series matching resistor and a fourth series matching resistor, respectively. One end of the third pull-up resistor, one end of the fourth pull-up series matching resistor, one end of the output filter capacitor, and the output power supply VCC2 terminal of the bidirectional isolator ISO1640 are all connected to the output end of the three-stage DIP switch. The other ends of the third pull-up resistor and the fourth pull-up resistor are respectively connected to the SDA2 and SCL2 terminals of the bidirectional isolator ISO1640. The other end of the output filter capacitor and the GND2 terminal of the bidirectional isolator ISO1640 are both connected to the isolation ground.

[0023] In one embodiment, the MCU simulation debugger further includes a three-color LED indicator light control circuit and a buzzer control circuit connected to the minimum system of the main control chip.

[0024] In one embodiment, the MCU simulation debugger further includes an OLED display connected to the minimum system of the main control chip.

[0025] In one embodiment, the power supply port of the USB power supply and communication circuit module is a Type-C USB port.

[0026] The MCU emulator debugger with high-voltage isolation protection includes a USB power supply and communication circuit module, a first DC step-down circuit, a DC-DC power isolation module, a second DC step-down circuit, a minimum system for the main control chip, a flash control circuit for external code storage, an offline burn button detection circuit, a JTAG emulation / IIC burn interface isolation module, a three-stage DIP switch, a DIP switch status detection module, and a machine burn control interface. The JTAG emulation / IIC burn interface isolation module provides 1500Vrms electrical isolation between the debug board and the emulator device. When the debug board operates on 220V / 50Hz AC power, it can safely and stably perform online emulation and debugging operations without powering on. Software developers no longer need to worry about the electrical isolation of the debug board, but can focus solely on debugging the code. The emulator supports high-speed emulation and burning with multiple interfaces and multiple levels, and quickly switches the debug board's levels via DIP switches, greatly improving emulator level compatibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A block diagram of an MCU emulator debugger with high-voltage isolation protection in one embodiment;

[0028] Figure 2 This is an isolated 3.3V / 5V power supply in another embodiment, where (a) is a schematic diagram of a DC-DC power supply isolation module, and (b) is a schematic diagram of a second DC step-down circuit;

[0029] Figure 3 A schematic diagram of a DC-DC isolated power supply principle in another embodiment;

[0030] Figure 4 is a schematic diagram of a first DC step-down circuit in another embodiment;

[0031] Figure 5 A schematic diagram of the capacitive signal isolation principle in another embodiment;

[0032] Figure 6 A schematic diagram of the principle of a simulation / burning digital signal isolation module in another embodiment;

[0033] Figure 7 A power tree diagram of an MCU simulation debugger in another embodiment;

[0034] Figure 8 This is an overall structural diagram of an MCU simulation debugger in another embodiment. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0036] In one embodiment, Figure 1 As shown, an MCU simulation debugger with high-voltage isolation protection is provided, which includes a USB power supply and communication circuit module 1, a first DC step-down circuit 11, a DC-DC power isolation module 2, a second DC step-down circuit 3, a main control chip minimum system 4, a burning code external storage FLASH control circuit 5, an offline burning BURN button detection circuit 6, a JTAG simulation / IIC burning interface isolation module 7, a three-stage DIP switch 8, a DIP switch status detection module 9, and a machine burning control interface 10.

[0037] The first output end of the USB power supply and communication circuit module 1 is connected to the input end of the first DC step-down circuit 11, and the output end of the first DC step-down circuit is connected to the power end of the main control chip minimum system 4; the output end of the first DC step-down circuit 11 is connected to the input power end of the JTAG simulation / IIC burning interface isolation module 7.

[0038] The second output end of the USB power supply and communication circuit module 1 is connected to the DC-DC power supply isolation module 2, the first output end of the DC-DC power supply isolation module 2 is connected to the second DC step-down circuit 3, the output end of the second DC step-down circuit 3 is connected to the first input end of the three-stage dip switch 8, the second output end of the DC-DC power supply isolation module 2 is connected to the second input end of the three-stage dip switch 8, the output end of the three-stage dip switch 8 is connected to the output power supply end VCC2 of the JTAG simulation / IIC burning interface isolation module 7; the three-stage dip switch 8 is connected to the dip switch status detection module 9.

[0039] The grounds of the USB power supply and communication circuit module 1, the first DC step-down circuit 11, the main control chip minimum system 4, and the input end of the DC-DC power supply isolation module 2 are all connected to the input ground, and the grounds of the output end of the DC-DC power supply isolation module 2, the second DC step-down circuit 3, the three-stage dip switch 8, and the output end of the JTAG simulation / IIC burning interface isolation module 7 are all connected to the isolation ground.

[0040] The external storage FLASH control circuit 5 for burning code, the offline burning BURN button detection circuit 6, the JTAG simulation / IIC burning interface isolation module 7, the DIP switch state detection module 9 and the machine burning control interface 10 are all connected to the main control chip minimum system 4.

[0041] Specifically, the USB power supply and communication circuit module 1 is used for system power supply, IDE software or burning host computer software and communication with the emulator.

[0042] The DC-DC power supply isolation module 2 is used for electrical isolation between the USB power input and output terminals.

[0043] The second DC step-down circuit 3 is used to step down the voltage output by the DC-DC power supply isolation module 2 to provide power to the output end of the JTAG simulation / IIC burning interface isolation module 7.

[0044] The external storage FLASH control circuit 5 of the burning code is used for the offline burning function supported by the MCU simulation debugger. After the user saves the burning firmware to the external FLASH through the host computer software, the user can use the offline burning BURN button to perform firmware offline burning without using a computer.

[0045] The dial switch status detection module 9, i.e. the 5V / 3.3V / neutral dial switch status detection module, is used to detect the voltage gear currently selected for output. When neutral is selected, the OLED screen will flash and display "0V" as a prompt, indicating that the emulator does not output power at this time and the debugging board uses external power supply.

[0046] The machine programming control interface 10 is used to detect the machine "START" signal to start offline programming and output the machine programming status signal: "OK" signal, "NG" signal.

[0047] The JTAG simulation / IIC burning interface isolation module 7 is used to connect the emulator simulation / burning port to the debug board download port after signal isolation processing, which can perform KEIL simulation debugging and host computer IIC burning. In order to solve the above pain points, this is the module that the utility model focuses on implementing, and specifically adopts the following technical solutions:

[0048] The MCU emulator debugger is powered by a Type-C USB port. The USB input power first passes through a DC-DC isolation module (B0505S-2W) for 1500Vrms electrical isolation between the input and output ends. ① The USB input power passes through the first DC step-down circuit 11, converting the 5V power supply to 3.3V via the voltage regulator and step-down module. The power is then connected to the VCC and GND terminals of the emulator's main control chip, Minimum System 4, and the VCC1 and GND1 terminals of the digital signal isolation module (ISO1640, 3500Vrms isolation).

[0049] ② USB power is fed into the input (source) of DC-DC power isolation module 2. After isolation, DC-DC power isolation module 2 generates an isolated 5V output. The first 5V output of DC-DC power isolation module 2 is converted to 3.3V by a voltage regulator and step-down module (AMS1117-3.3). This voltage is then connected to the 3.3V position of the three-position DIP switch. The 3.3V output position is connected to VCC2 of the digital signal isolation module (ISO1640) via the DIP switch. The second 5V output of DC-DC power isolation module 2 is directly connected to the 5V position of the three-position DIP switch. The 5V output position is connected to VCC2 of the digital signal isolation module (ISO1640) via the DIP switch. The ground of the DC-DC power isolation module 2 output is connected to GND2 of the digital signal isolation module (ISO1640). Finally, the three-position DIP switch 8 is used to select between 3.3V, 5V, or neutral.

[0050] The above solution achieves electrical isolation between the simulator's programming interface and the debug board's programming interface in principle. Simultaneously, the copper layer is hollowed out to comply with the IEC 60950 (International Electrotechnical Commission; "Safety Standard for Information Technology Equipment") electrical creepage distance isolation standard in the PCB layout design. Because the debugged board is on the primary side (hot ground) and the debugger is on the secondary side (cold ground), IEC 60950 imposes strict requirements on reinforced insulation. Reinforced insulation requires a clearance and creepage distance of 4mm / 5mm between the primary and secondary sides, respectively. Therefore, the debugger's PCB clearance and creepage distances are designed to be 4mm / 5mm, further ensuring the effectiveness of electrical isolation.

[0051] The emulator not only has functions such as online / offline burning, but also can realize online simulation debugging of resistor product firmware, especially the firmware code of 220V / 50Hz household appliances that can be debugged under power, thereby effectively solving the pain points encountered by developers when designing and debugging code in the above technical background and avoiding possible risks.

[0052] The MCU emulator debugger with high-voltage isolation protection includes a USB power supply and communication circuit module, a first DC step-down circuit, a DC-DC power isolation module, a second DC step-down circuit, a minimum system for the main control chip, a flash memory control circuit for external code burning, a burn button detection circuit for offline burning, a JTAG emulation / IIC burning interface isolation module, a three-stage DIP switch, a DIP switch status detection module, and a machine burning control interface. The JTAG emulation / IIC burning interface isolation module provides 1500Vrms electrical isolation between the debug board and the emulator device. When the debug board operates on 220V / 50Hz AC power, it can safely and stably perform online emulation and debugging without power failure. Software developers no longer need to worry about the electrical isolation of the debug board, but can focus solely on debugging the code. The module supports high-speed emulation and burning with multiple interfaces and multiple levels, and quickly switches the debug board's levels via DIP switches, greatly improving emulator level compatibility.

[0053] In one embodiment, Figure 2 As shown in (a), the DC-DC power supply isolation module includes: a first first filter capacitor C48, a first second filter capacitor C49, a second first filter capacitor C423, a second second filter capacitor C51 and an isolated voltage-stabilized power supply module U11.

[0054] The first output end of the USB power supply and communication circuit module is connected to the voltage input end VI+ of the isolated voltage-stabilized power supply module U11, and the GND end of the isolated voltage-stabilized power supply module U11 is connected to the input ground; the first first filter capacitor C48 and the first second filter capacitor C49 are both connected in parallel between the voltage input end VI+ and the GND end of the isolated voltage-stabilized power supply module U11.

[0055] The positive output terminal VO+ of the isolated voltage-stabilized power supply module U11 is used to output the isolated voltage 5V_OUT; the negative output terminal VO- of the isolated voltage-stabilized power supply module U11 is connected to the isolation ground; the second first filter capacitor C423 and the second second filter capacitor C51 are both connected in parallel between the positive output terminal VO+ and the negative output terminal VO- of the isolated voltage-stabilized power supply module U11; the positive output terminal VO+ of the isolated voltage-stabilized power supply module U11 is connected to the second input terminal of the three-stage dip switch, the output terminal of the three-stage dip switch is connected to the output power terminal VCC2 of the JTAG simulation / IIC burning interface isolation module, and the output terminal of the three-stage dip switch, the output terminal of the JTAG simulation / IIC burning interface isolation module, and the output terminal of the isolated voltage-stabilized power supply module are grounded.

[0056] Specifically, the principle of power isolation is as follows Figure 3As shown in the figure, the DC-DC isolation module uses high-speed switching power switches (Q1, Q2, Q3, and Q4 in the figure) to convert the input DC voltage into AC voltage, which is then output to the primary winding of the internal transformer. Mutual inductance coupling through the transformer achieves isolated voltage conversion. Mutual inductance coupling through the secondary winding of the transformer generates AC voltage, which, after passing through a subsequent rectification and voltage regulation circuit (the full-bridge rectifier circuit composed of D1, D2, D3, and D4 in the figure), is output as an isolated DC power supply, achieving isolation between Vin / GND and Vout / AGND. Given the aforementioned mechanism of the DC-DC isolation module, this utility model uses a DC-DC module (B0505S-2W) to isolate the USB port input power (Vin).

[0057] In one embodiment, the isolated voltage-stabilized power supply module is an isolated voltage-stabilized power supply module with a 5V DC input and a 5V DC output. Preferably, the isolated voltage-stabilized power supply module is a B0505S-2W isolated voltage-stabilized power supply module.

[0058] The emulator's USB input power is supplied by a B0505S-2W DC-DC isolated power supply, which achieves electrical isolation between the input source and the output power.

[0059] The first DC step-down circuit is as follows Figure 4 As shown, the first DC step-down circuit includes an AMS1117-3.3 voltage regulator and step-down module U9, a capacitor C17, a capacitor C18, a capacitor C19, a capacitor C20, a capacitor C21, a capacitor C22, a capacitor C23, a capacitor C24, a capacitor C25, and a capacitor C26.

[0060] (1) A set of power and ground of the USB port are connected to pin 3 and pin 1 of the AMS1117-3.3 voltage regulator and buck module U9 respectively. Pin 2 and pin 1 of the AMS1117-3.3 voltage regulator and buck module U9 are connected to pin 1 and pin 4 of U12 and pin 1 and pin 4 of U13 respectively.

[0061] (2) The other power supply and ground of the USB port are connected to pins 1 and 2 of U11 respectively. Pins 6 and 4 of U11 are the isolated output power supply and ground. After passing through the three-stage DIP switch SW1, they are connected to the power supply and ground of U12 / U13 (pins 8 and 5 of U12, and pins 8 and 5 of U13). The positive output terminal VO+ and negative output terminal VO- corresponding to pins 6 and 4 of U11 are connected to pins 3 and 1 of U14. Pins 2 and 1 of U14 are connected to the power supply and ground of U12 and U13 (pins 8 and 5 of U12, and pins 8 and 5 of U13) after passing through the three-stage DIP switch SW1. Through the above circuit, the isolation of 3.3V / 5V power supply is achieved.

[0062] In one embodiment, Figure 2 As shown in (b), the second DC step-down circuit includes a first directional filter capacitor C424, a second directional filter capacitor C426, a first third filter capacitor C425, a second third filter capacitor C428, a third third filter capacitor C429, a fourth filter capacitor C427 and a voltage stabilizing and step-down module U14.

[0063] The input terminal IN of the voltage stabilizing and step-down module U14 is connected to the output terminal of the DC-DC power supply isolation module to receive the isolated voltage 5V_OUT. The positive terminal of the first directional filter capacitor C424 and one end of the first third filter capacitor C425 are both connected to the input terminal IN of the voltage stabilizing and step-down module U14. The negative terminal of the first directional filter capacitor C424 and the other end of the first third filter capacitor C425 are both connected to the GND terminal of the voltage stabilizing and step-down module U14. The GND terminal of the voltage stabilizing and step-down module U14 is connected to the isolation ground.

[0064] The positive end of the second directional filter capacitor C426, one end of the fourth filter capacitor C427, one end of the second third filter capacitor C428, and one end of the third third filter capacitor C429 are all connected to the output end OUT of the voltage stabilizing and bucking module U14. The output end OUT of the voltage stabilizing and bucking module U14 outputs a 3.3V voltage. The negative end of the second directional filter capacitor C426, the other end of the fourth filter capacitor C427, the other end of the second third filter capacitor C428, and the other end of the third third filter capacitor C429 are all connected to the GND end of the voltage stabilizing and bucking module U14.

[0065] The output terminal OUT of the voltage regulator and step-down module U14 is connected to the second input terminal of the three-stage DIP switch, and the output terminal of the three-stage DIP switch is connected to the output power terminal VCC2 of the JTAG simulation / IIC burning interface isolation module;

[0066] The output ends of the voltage regulator and step-down module, three-stage DIP switch, and JTAG simulation / IIC burning interface isolation module have a common ground (the common point is the isolation ground).

[0067] In one embodiment, the voltage regulator and buck module is a forward low-dropout voltage regulator with an output voltage of 3.3 V. Preferably, the voltage regulator and buck module is an AMS1117-3.3 voltage regulator and buck module for converting a 5 V power supply into 3.3 V.

[0068] In one embodiment, the JTAG emulation / IIC programming interface isolation module includes two identical isolation channels. The first isolation channel includes: an input filter capacitor C52, a first series matching resistor R43, a second series matching resistor R45, a first pull-up resistor R39, a second pull-up resistor R40, a bidirectional isolator ISO1640 U12, an output filter capacitor C53, a third series matching resistor R44, a fourth series matching resistor R46, a third pull-up resistor R41, and a fourth pull-up resistor R42.

[0069] The SDA1 and SCL1 terminals of the bidirectional isolator ISO1640 U12 are connected to the minimum system of the main control chip through a first series matching resistor R43 and a second series matching resistor R45, respectively. One end of the first pull-up resistor R39, one end of the second pull-up resistor R40, one end of the input filter capacitor C52, and the input power supply VDD1 of the bidirectional isolator ISO1640 U12 are all connected to the output end of the first DC step-down circuit. One end of the first pull-up resistor R39 and the other end of the second pull-up resistor R40 are connected to the SCL1 and SDA1 terminals of the bidirectional isolator ISO1640 U13, respectively. The other end of the input filter capacitor C52 and the GND1 terminal of the bidirectional isolator ISO1640 U12 are both connected to the GND terminal of the first DC step-down circuit, where the GND terminal of the first DC step-down circuit is connected to the input ground.

[0070] The SDA2 and SCL2 terminals of the bidirectional isolator ISO1640 U12 are connected to the minimum system of the main control chip through the third series matching resistor R44 and the fourth series matching resistor R46, respectively. One end of the third pull-up resistor R41, one end of the fourth pull-up resistor R42, one end of the output filter capacitor, and the output power supply VCC2 of the bidirectional isolator ISO1640 U13 are all connected to the output end of the three-stage DIP switch. The other ends of the third pull-up resistor R41 and the fourth pull-up resistor R42 are connected to the SDA2 and SCL2 terminals of the bidirectional isolator ISO1640 U12, respectively. The other end of the output filter capacitor and the GND2 terminal of the bidirectional isolator ISO1640 U12 are both connected to the isolation ground.

[0071] The structure of the second isolation channel is the same as that of the first isolation channel. Figure 6 shown.

[0072] Specifically, existing signal isolation methods mainly include optocoupler, electromagnetic and capacitive isolation. Optocoupler and electromagnetic isolation are relatively slow and are not suitable for high-speed download applications of simulators. Capacitive isolation has the characteristics of good electrical isolation effect and strong anti-interference ability. This utility model uses a capacitive isolation bidirectional isolator (ISO1640), which mainly utilizes the basic characteristics of capacitors that isolate direct current and pass alternating current. The principle of capacitive signal isolation is as follows: Figure 5 As shown, the input signal INPUT1 (emulator simulation signal) is coupled to the output end INPUT2 (debugging board simulation signal). The isolation channel consists of two reverse-propagation digital isolation channels, and an internal bias circuit is added on the input side to avoid signal latching problems and achieve effective level conversion.

[0073] like Figure 6 As shown, the bidirectional isolator (ISO1640) includes 8 pins, pin 1 corresponds to the power supply VDD1, pin 2 corresponds to the SDA1 end, pin 3 corresponds to the SCL1 end, pin 4 corresponds to the ground GND1, pin 5 corresponds to the VCC2 end, pin 6 corresponds to the SDA2 end, pin 7 corresponds to the SCL1 end, and pin 8 corresponds to the GND2 end.

[0074] Pins 2 and 3 of the bidirectional isolator (ISO1640) U12 are respectively connected to the main MCU signal output GPIO pins M_JTCK_I / M_JTDI_I, and one end of pins 6 and 7 of the bidirectional isolator (ISO1640) U12 are connected to the download signal port JTDI_OUT / JTCK_OUT of the debugging board. The power supply on the right side of the bidirectional isolator (ISO1640) U12 (pin 8 of U12 corresponds to the power supply VCC2, and pin 5 of U12 corresponds to the ground GND2) and the power supply on the left side of the bidirectional isolator (ISO1640) U12 (pin 1 of U12 corresponds to the power supply VDD1, and pin 4 of U12 corresponds to the ground GND1) are isolated and separated.

[0075] Pins 2 and 3 of the bidirectional isolator (ISO1640) U13 are respectively connected to the main MCU signal output GPIO pins M_JTDO_I / M_JTMS_I, and one end of pins 6 and 7 of the bidirectional isolator (ISO1640) U13 are connected to the download signal port JTMS_OUT / JTDO_OUT of the debugging board. The power supply on the left side of the bidirectional isolator (ISO1640) U13 (the power supply VDD1 corresponding to pin 1 of U13 and the ground GND1 corresponding to pin 4 of U13) and the power supply on the right side of the bidirectional isolator (ISO1640) U13 (the power supply VDD1 corresponding to pin 8 of U13 and the ground GND1 corresponding to pin 5 of U13) are isolated and divided.

[0076] The JTAG simulation / IIC burning download port of the MCU simulation debugger is connected to the debug board download port by adding a bidirectional isolator ISO1640.

[0077] In one embodiment, the MCU simulation debugger further includes a three-color LED indicator light control circuit and a buzzer control circuit connected to the minimum system of the main control chip.

[0078] Specifically, the three-color LED control circuit and the buzzer control circuit are used to indicate the operation status, such as: running, operation successful, and operation failed.

[0079] KEIL and the host computer software communicate with the emulator through the USB port, and the emulator communicates with the debugging board through the JTAG emulation / IIC burning isolation module.

[0080] The workflow of this MCU emulator debugger is as follows: ① When operating the KEIL IDE debugging software, KEIL sends the corresponding emulation debugging instruction data based on the operation type. After receiving the data, the emulator converts the data into a JTAG protocol data stream and then sends the data stream to the debug board MCU JTAG interface via the following JTAG emulation / IIC burning isolation interface. The debug board MCU executes the emulation debugging process according to the JTAG protocol state machine, and the three-color (RGB) LED indicates the operation status. ② When operating the host computer software, the host computer software sends the corresponding burning instruction based on the operation type. After receiving the instruction, the emulator sends the data stream to the debug board MCU via the JTAG emulation / IIC burning isolation interface in IIC mode for FLASH burning. The three-color (RGB) LED and buzzer indicate the operation status.

[0081] In one embodiment, the MCU simulation debugger further includes an OLED display connected to the minimum system of the main control chip.

[0082] Specifically, the OLED LCD screen control circuit is used to display information such as the emulator's software version information, product signals, simulation debugging information, and offline burning firmware information (target MCU model, firmware name, firmware checksum, burning statistics).

[0083] In one embodiment, the power supply port of the USB power supply and communication circuit module is a Type-C USB port.

[0084] The power tree diagram of the MCU simulator debugger shows the power supply path of this system. Figure 7As shown in the figure, the total input power supply (DC 5V) from the Type-C port is divided into two branches: Branch 1 is the non-isolated path, where the total input power is stepped down to DC 3.3V by an LDO and then output to the MCU's minimum system power supply and the non-isolated power pin of the isolation chip. Branch 2 is the isolated path, where the total input power passes through the DC-DC isolation power module and is output to the LDO input. After being stepped down to DC 3.3V, it is output to the peripheral interface of the level isolation conversion module, thus achieving electrical isolation of the power system.

[0085] In a specific implementation, the overall structure of the MCU simulation debugger is as follows: Figure 8 As shown, among them: ① is the upper cover of the simulator product; ② is the bottom shell of the simulator product; ③ is the fixing screw.

[0086] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0087] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. An MCU simulation debugger with high voltage isolation protection, characterized in that: The MCU simulation debugger includes: a USB power supply and communication circuit module, a first DC step-down circuit, a DC-DC power isolation module, a second DC step-down circuit, a main control chip minimum system, a burning code external storage FLASH control circuit, an offline burning BURN button detection circuit, a JTAG simulation / IIC burning interface isolation module, a three-stage DIP switch, a DIP switch status detection module and a machine burning control interface; The first output end of the USB power supply and communication circuit module is connected to the input end of the first DC step-down circuit, and the output end of the first DC step-down circuit is connected to the power end of the minimum system of the main control chip; the output end of the first DC step-down circuit is connected to the input power end of the JTAG simulation / IIC burning interface isolation module; The second output end of the USB power supply and communication circuit module is connected to the DC-DC power supply isolation module, the first output end of the DC-DC power supply isolation module is connected to the second DC step-down circuit, the output end of the second DC step-down circuit is connected to the first input end of the three-stage DIP switch, the second output end of the DC-DC power supply isolation module is connected to the second input end of the three-stage DIP switch, and the output end of the three-stage DIP switch is connected to the output power end VCC2 of the JTAG simulation / IIC burning interface isolation module; the three-stage DIP switch is connected to the DIP switch status detection module; The grounds of the USB power supply and communication circuit module, the first DC step-down circuit, the main control chip minimum system, and the input end of the DC-DC power supply isolation module are all connected to the input ground, and the grounds of the output end of the DC-DC power supply isolation module, the second DC step-down circuit, the three-stage DIP switch, and the output end of the JTAG simulation / IIC burning interface isolation module are all connected to the isolation ground; The burning code external storage FLASH control circuit, the offline burning BURN button detection circuit, the JTAG simulation / IIC burning interface isolation module, the DIP switch state detection module and the machine burning control interface are all connected to the main control chip minimum system.

2. The MCU simulation debugger with high-voltage isolation protection according to claim 1, characterized in that: The DC-DC power supply isolation module includes: two first filter capacitors, two second filter capacitors and an isolated voltage-stabilized power supply module; The first output terminal of the USB power supply and communication circuit module is connected to the voltage input terminal of the isolated voltage-stabilized power supply module, and the GND terminal of the isolated voltage-stabilized power supply module is connected to the input ground; the first first filter capacitor and the second second filter capacitor are both connected in parallel between the voltage input terminal and the GND terminal of the isolated voltage-stabilized power supply module; The positive output end of the isolated voltage-stabilized power supply module is used to output the isolated voltage; the negative output end of the isolated voltage-stabilized power supply module is connected to the isolation ground; the second first filter capacitor and the second second filter capacitor are both connected in parallel between the positive output end and the negative output end of the isolated voltage-stabilized power supply module; the positive output end of the isolated voltage-stabilized power supply module is connected to the second input end of the three-stage dip switch, the output end of the three-stage dip switch is connected to the output power end VCC2 of the JTAG simulation / IIC burning interface isolation module, and the three-stage dip switch, the output end of the JTAG simulation / IIC burning interface isolation module and the output end of the isolated voltage-stabilized power supply module are grounded.

3. The MCU simulation debugger with high-voltage isolation protection according to claim 2, characterized in that: The isolated voltage-stabilized power supply module is an isolated voltage-stabilized power supply module that inputs a 5V DC voltage and outputs a 5V DC voltage.

4. The MCU simulation debugger with high-voltage isolation protection according to claim 1, characterized in that: The second DC step-down circuit includes two directional filter capacitors, three third filter capacitors, one fourth filter capacitor and a voltage stabilizing and step-down module; The input end of the voltage stabilizing and bucking module is connected to the output end of the DC-DC power supply isolation module, the positive end of the first directional filter capacitor and one end of the first third filter capacitor are both connected to the input end of the voltage stabilizing and bucking module, the negative end of the first directional filter capacitor and the other end of the first third filter capacitor are both connected to the GND end of the voltage stabilizing and bucking module, and the GND end of the voltage stabilizing and bucking module is connected to the isolation ground; The positive end of the second directional filter capacitor, one end of the fourth filter capacitor, one end of the second third filter capacitor, and one end of the third third filter capacitor are all connected to the output end of the voltage stabilizing and bucking module, the output end of the voltage stabilizing and bucking module outputs a 3.3V voltage, and the negative end of the second directional filter capacitor, the other end of the fourth filter capacitor, the other end of the second third filter capacitor, and the other end of the third third filter capacitor are all connected to the GND end of the voltage stabilizing and bucking module; The output end of the voltage stabilizing and step-down module is connected to the second input end of the three-stage DIP switch, and the output end of the three-stage DIP switch is connected to the output power end VCC2 of the JTAG simulation / IIC burning interface isolation module; The output ends of the voltage stabilizing and step-down module, the three-stage DIP switch and the JTAG simulation / IIC burning interface isolation module share a common ground.

5. The MCU simulation debugger with high-voltage isolation protection according to claim 4, characterized in that: The voltage stabilizing and step-down module is a forward low-dropout voltage regulator with an output voltage of 3.3V.

6. The MCU simulation debugger with high-voltage isolation protection according to claim 1, characterized in that: The JTAG simulation / IIC burning interface isolation module includes two isolation channels with the same structure; The isolation channel includes: an input filter capacitor, four series matching resistors, a bidirectional isolator ISO1640, an output filter capacitor, and four pull-up resistors; The SDA1 and SCL1 terminals of the bidirectional isolator ISO1640 are connected to the minimum system of the main control chip through a first series matching resistor and a second series matching resistor, respectively. One end of the first pull-up resistor, one end of the second pull-up resistor, one end of the input filter capacitor, and the input power supply VDD1 of the bidirectional isolator ISO1640 are all connected to the output end of the first DC step-down circuit. The other ends of the first pull-up resistor and the second pull-up resistor are respectively connected to the SCL1 and SDA1 terminals of the bidirectional isolator ISO1640. The other end of the input filter capacitor and the GND1 terminal of the bidirectional isolator ISO1640 are both connected to the GND terminal of the first DC step-down circuit. The SDA2 and SCL2 terminals of the bidirectional isolator ISO1640 are connected to the minimum system of the main control chip through a third series matching resistor and a fourth series matching resistor, respectively. One end of the third pull-up resistor, one end of the fourth pull-up series matching resistor, one end of the output filter capacitor, and the output power supply VCC2 terminal of the bidirectional isolator ISO1640 are all connected to the output end of the three-stage DIP switch. The other ends of the third pull-up resistor and the fourth pull-up resistor are respectively connected to the SDA2 and SCL2 terminals of the bidirectional isolator ISO1640. The other end of the output filter capacitor and the GND2 terminal of the bidirectional isolator ISO1640 are both connected to the isolation ground.

7. The MCU simulation debugger with high-voltage isolation protection according to claim 1, characterized in that: The MCU simulation debugger also includes a three-color LED indicator light control circuit and a buzzer control circuit connected to the minimum system of the main control chip.

8. The MCU simulation debugger with high-voltage isolation protection according to claim 1, characterized in that: The MCU simulation debugger also includes an OLED display connected to the minimum system of the main control chip.

9. The MCU simulation debugger with high-voltage isolation protection according to claim 1, wherein The power supply port of the USB power supply and communication circuit module is a Type-C USB port.

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