Signal transmission method and circuit based on MOS tube

Abstract

The invention discloses a signal transmission method and circuit based on an MOS transistor, and the method comprises the steps: obtaining the temperature information of the MOS transistor, so as to generate a bias voltage corresponding to the MOS transistor; superposing the bias voltage and an externally input signal to generate a superposed signal; and inputting the superposed signal to the MOS tube, and completing the transmission of the signal through the MOS tube so as to reduce the distortion in the signal transmission process.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic circuits, and in particular to a signal transmission method and circuit based on MOS tubes. Background Art

[0002] MOSFET is a metal oxide semiconductor field effect transistor, also known as gold oxide semiconductor field effect transistor. Its main characteristics are high power, high voltage resistance, low static power consumption and fast switching speed. Therefore, MOSFET is widely used in various electronic devices, such as switches and motor drives, power management, automotive electronic systems and other high-power application scenarios.

[0003] When the MOSFET is used for signal transmission, a bias voltage needs to be provided to the MOSFET so that it operates within a linear range, thereby avoiding waveform distortion when the signal is output through the MOSFET.

[0004] In the prior art, the bias voltage corresponding to the MOSFET is usually generated by resistor voltage division or VBE voltage multiplication. However, the above methods cannot adjust the bias voltage without changing the circuit components to adapt to different types of MOSFETs. When different types of MOSFETs need to be replaced, it is necessary to change the resistors and other components in the circuit, which causes huge time and economic costs. At the same time, the Vgs threshold voltage of the MOSFET has a relatively large temperature drift. In the case of large temperature changes, the above methods cannot achieve automatic temperature compensation, resulting in inaccurate bias voltage provided to the MOSFET, which in turn causes distortion during signal transmission. Summary of the invention

[0005] In order to solve the above technical problems, the present invention discloses a signal transmission method and circuit based on MOS tube, which are used to reduce the distortion of the signal during the transmission process.

[0006] In order to achieve the above object, the present invention discloses a signal transmission method based on a MOS tube, comprising:

[0007] Acquiring temperature information of the MOS tube to generate a bias voltage corresponding to the MOS tube;

[0008] Superimposing the bias voltage with an external input signal to generate a superimposed signal;

[0009] The superimposed signal is input to the MOS tube, and the signal is transmitted through the MOS tube.

[0010] The present invention discloses a signal transmission method based on a MOS tube, which generates a bias voltage corresponding to the MOS tube by acquiring the temperature information of the MOS tube, so that the bias voltage generated according to the temperature of the MOS tube can compensate for the temperature drift of the gate threshold voltage of the MOS tube, thereby improving the accuracy of the generated bias voltage, and then superimposing the generated bias voltage on an external input signal, and inputting the superimposed signal generated after superposition into the MOS tube, so as to control the MOS tube to work in a linear range according to the precise bias voltage in the superimposed signal, so that the signal is not distorted when it is output through a MOSFET, thereby reducing the distortion of the signal during transmission.

[0011] As a preferred example, the step of acquiring the temperature information of the MOS tube to generate a bias voltage corresponding to the MOS tube includes:

[0012] Obtaining a temperature and gate threshold voltage relationship table corresponding to the MOS tube;

[0013] According to the temperature information, query the temperature and gate threshold voltage relationship table to obtain the gate threshold voltage corresponding to the temperature information;

[0014] A gate voltage corresponding to the MOS tube is obtained, and the gate voltage is compared with the gate threshold voltage to determine a bias voltage corresponding to the MOS tube according to a result of the comparison.

[0015] The present invention can compensate for the temperature drift of the gate threshold voltage of the MOSFET by collecting the bias voltage generated by the temperature information on the MOSFET, so as to improve the stability of the MOSFET working in the linear range. At the same time, the present invention uses the relationship table corresponding to different types of MOSFETs to solve the temperature drift problem of the gate threshold voltage without changing the circuit, thereby being compatible with multiple types of MOSFETs.

[0016] As a preferred example, the step of superimposing the bias voltage with an external input signal to generate a superimposed signal includes:

[0017] Collecting the signal input externally, and amplifying the signal to generate a first signal;

[0018] The first signal is superimposed on the bias voltage to generate the superimposed signal.

[0019] The present invention amplifies the external input signal before superimposing the bias voltage to enhance the driving capability of the signal and further reduce the distortion of the signal transmission process. Then the bias voltage is superimposed on the amplified signal, so that the MOSFET operates in a linear range according to the bias voltage in the superimposed signal, so that the signal is not distorted when it is output through the MOSFET.

[0020] On the other hand, the present invention discloses a signal transmission circuit based on a MOS tube, including a main control unit, a temperature information acquisition unit, a bias voltage providing circuit, and a signal superposition circuit;

[0021] The temperature information acquisition unit is connected to the main control unit by signal, and is used to obtain the temperature information of the MOS tube and send the temperature information to the main control unit;

[0022] The main control unit is connected to the bias voltage providing circuit signal, and is used to control the bias voltage providing circuit to generate a bias voltage corresponding to the MOS tube according to the temperature information, and send the bias voltage to the signal superposition circuit;

[0023] The input end of the signal superposition circuit is connected to the output end of the bias voltage providing circuit, and is used to receive the bias voltage and superimpose the bias voltage with an external input signal to generate a superimposed signal;

[0024] The output end of the signal superposition circuit is connected to the input end of the MOS tube, and is used to input the superposition signal into the MOS tube, so as to complete the transmission of the signal through the MOS tube.

[0025] The present invention discloses a signal transmission circuit based on a MOS tube, which obtains the temperature information of the MOS tube through a temperature information acquisition unit, so that the main control unit controls the bias voltage providing circuit to generate a bias voltage corresponding to the MOS tube according to the temperature information, so that the bias voltage generated by the bias voltage providing circuit can compensate for the temperature drift of the gate threshold voltage of the MOS tube, thereby improving the accuracy of the generated bias voltage. Then the signal superposition circuit superimposes the generated bias voltage on the external input signal, and inputs the superimposed signal generated after superposition into the MOS tube, so as to control the MOS tube to work in a linear range according to the precise bias voltage in the superimposed signal, so that the signal is not distorted when it is output through the MOSFET, and the distortion of the signal during transmission is reduced.

[0026] As a preferred example, the main control unit is also used to obtain a temperature and gate threshold voltage relationship table corresponding to the MOS tube; query the temperature and gate threshold voltage relationship table according to the temperature information to obtain the gate threshold voltage corresponding to the temperature information; obtain the gate voltage corresponding to the MOS tube, and compare the gate voltage with the gate threshold voltage to control the bias voltage providing circuit to generate the bias voltage corresponding to the MOS tube according to the comparison result.

[0027] The present invention can compensate for the temperature drift of the gate threshold voltage of the MOSFET by collecting the bias voltage generated by the temperature information on the MOSFET, so as to improve the stability of the MOSFET working in the linear range. At the same time, the present invention uses the relationship table corresponding to different types of MOSFETs, and can solve the temperature drift problem of the gate threshold voltage through the main control unit without changing the circuit, thereby being compatible with multiple types of MOSFETs.

[0028] As a preferred example, it also includes a signal enhancement circuit; the signal enhancement circuit includes a first operational amplifier and a first resistor, which are used to collect the external input signal and amplify the signal to generate a first signal; wherein, the input end of the first operational amplifier is used to receive the external input signal, and the output end of the first operational amplifier is connected to the first end of the first resistor; the second end of the first resistor is connected to the input end of the signal superposition circuit.

[0029] The present invention amplifies the external input signal before superimposing the bias voltage to enhance the driving capability of the signal and further reduce the distortion of the signal transmission process. At the same time, the first resistor is set in the signal enhancement circuit to ensure that the first operator amplifies the signal without distortion.

[0030] As a preferred example, the signal superposition circuit is an adder circuit composed of operational amplifiers or a subtractor circuit composed of operational amplifiers.

[0031] The present invention utilizes an adder and a subtractor to complete the superposition of a signal and a bias voltage, so that in the process of signal transmission, the MOS tube can ensure distortion-free transmission of the signal according to the superimposed bias voltage.

[0032] As a preferred example, it also includes a signal amplification circuit; the signal amplification circuit includes a second operational amplifier, a second resistor and a third resistor; wherein the second end of the first resistor and the output end of the signal superposition circuit are respectively connected to the in-phase input end of the second operational amplifier, and the output end of the second operational amplifier is connected to the input end of the MOS tube; the third end of the second resistor and the fourth end of the third resistor are respectively connected to the inverting input end of the second operational amplifier; the fifth end of the second resistor is grounded, and the sixth end of the third resistor is connected to the output end of the second operational amplifier.

[0033] The present invention provides the signal amplifying circuit to further amplify the superimposed signal so as to reduce the distortion in the signal transmission process as much as possible.

[0034] As a preferred example, the bias voltage providing circuit includes a DAC and a fourth resistor; wherein the control end of the DAC is connected to the main control unit signal, the output end of the DAC is connected to the seventh end of the fourth resistor; the eighth end of the fourth resistor is connected to the input end of the signal superposition circuit.

[0035] The present invention controls the DAC output bias voltage through the main control unit to adjust the MOS tube to ensure that the MOSFET works in the linear region. Furthermore, the fourth resistor is set in the bias voltage providing circuit to adjust the bias current of the MOSFET to improve the stability of the MOSFET working in the linear region.

[0036] As a preferred example, the main control unit determines the first bias voltage according to a comparison result between the gate voltage and the gate threshold voltage;

[0037] The main control unit determines the bias voltage output by the DAC according to the first bias voltage and the resistance values ​​corresponding to the first resistor, the second resistor, the third resistor, and the fourth resistor; wherein the calculation formula corresponding to the bias voltage is:

[0038] V DAC =V OS *(R 1 +R 4 ) / R 1 *(1+R 3 / R 2 )

[0039] Among them, the V DAC represents the bias voltage of the DAC output; the V OS represents the first bias voltage determined by the main control unit; the R 1 represents the first resistor; the R 2 represents the second resistor; the R 3represents the third resistor; the R 4 represents the fourth resistor.

[0040] After the main control unit determines the first bias voltage required by the MOS tube, in order to ensure that the voltage output by the DAC can accurately control the MOS tube to work in a linear range, the bias voltage output by the DAC is determined according to the resistance in the circuit and the first bias voltage, so that the MOS tube works in a linear range according to the bias voltage output by the DAC, so that the signal can be output without distortion. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 : A flow chart of a signal transmission method based on a MOS tube disclosed in an embodiment of the present invention;

[0042] Figure 2 : is a structural schematic diagram of a signal transmission circuit based on a MOS tube disclosed in an embodiment of the present invention;

[0043] Figure 3 : is a schematic structural diagram of a bias circuit disclosed in yet another embodiment of the present invention;

[0044] Figure 4 : is a structural schematic diagram of a signal transmission circuit disclosed in another embodiment of the present invention;

[0045] Figure 5 : is a connection diagram of an operational amplifier circuit and a signal amplification circuit disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] Embodiment 1

[0048] Reference Figure 1 , is a flow chart of a signal transmission method based on a MOS tube disclosed in an embodiment, which mainly includes steps 101 to 103, which are used to provide an adjustable bias voltage to the MOS to achieve distortion-free transmission of the signal. Specifically, the steps are:

[0049] Step 101: Acquire temperature information of a MOS tube to generate a bias voltage corresponding to the MOS tube.

[0050] In this embodiment, the step mainly includes: obtaining a temperature and gate threshold voltage relationship table corresponding to the MOS tube; querying the temperature and gate threshold voltage relationship table according to the temperature information to obtain the gate threshold voltage corresponding to the temperature information; obtaining the gate voltage corresponding to the MOS tube, and comparing the gate voltage with the gate threshold voltage to determine the bias voltage corresponding to the MOS tube according to the comparison result.

[0051] In this embodiment, this step can compensate for the temperature drift of the gate threshold voltage of the MOSFET by collecting the bias voltage generated by the temperature information on the MOSFET, so as to improve the stability of the MOSFET working in the linear range. At the same time, the present invention uses the relationship table corresponding to different types of MOSFETs to solve the temperature drift problem of the gate threshold voltage without changing the circuit, thereby being compatible with multiple types of MOSFETs.

[0052] Step 102: superimpose the bias voltage and an external input signal to generate a superimposed signal.

[0053] In this embodiment, the steps mainly include: collecting the external input signal, and amplifying the signal to generate a first signal; and superimposing the first signal on the bias voltage to generate the superimposed signal.

[0054] In this embodiment, this step amplifies the external input signal before superimposing the bias voltage to enhance the driving capability of the signal and further reduce the distortion of the signal transmission process. The bias voltage is then superimposed on the amplified signal so that the MOSFET operates in a linear range according to the bias voltage in the superimposed signal, so that the signal is not distorted when it is output through the MOSFET.

[0055] Step 103: input the superimposed signal into the MOS tube, and complete the transmission of the signal through the MOS tube.

[0056] On the other hand, refer to Figure 2 This embodiment also discloses a signal transmission circuit based on a MOS tube, specifically, including a main control unit 201, a temperature information acquisition unit 202, a bias voltage providing circuit 203, and a signal superposition circuit 204.

[0057] The temperature information acquisition unit 202 is connected to the main control unit 201 by signal, and is used to obtain the temperature information of the MOS tube and send the temperature information to the main control unit 201 .

[0058] The main control unit 201 is signal-connected to the bias voltage providing circuit 203 , and is used to control the bias voltage providing circuit 203 to generate a bias voltage corresponding to the MOS tube according to the temperature information, and send the bias voltage to the signal superposition circuit 204 .

[0059] The input end of the signal superposition circuit 204 is connected to the output end of the bias voltage providing circuit 203, and is used to receive the bias voltage and superimpose the bias voltage with an external input signal to generate a superimposed signal.

[0060] The output end of the signal superposition circuit 204 is connected to the input end of the MOS transistor, and is used to input the superposition signal to the MOS transistor, so as to complete the transmission of the signal through the MOS transistor.

[0061] In this embodiment, when the main control unit 201 controls the bias voltage providing circuit 203 to generate the bias voltage, it obtains the temperature and gate threshold voltage relationship table corresponding to the MOS tube, and then queries the temperature and gate threshold voltage relationship table according to the temperature information to obtain the gate threshold voltage corresponding to the temperature information, and finally obtains the gate voltage corresponding to the MOS tube, and compares the gate voltage with the gate threshold voltage, so as to control the bias voltage providing circuit 203 to generate the bias voltage corresponding to the MOS tube according to the comparison result.

[0062] In this embodiment, refer to Figure 2 , also includes a signal enhancement circuit 205; the signal enhancement circuit 205 includes a first operational amplifier and a first resistor, which are used to collect the external input signal and amplify the signal to generate a first signal; wherein the input end of the first operational amplifier is used to receive the external input signal, and the output end of the first operational amplifier is connected to the first end of the first resistor; the second end of the first resistor is connected to the input end of the signal superposition circuit 204.

[0063] In this embodiment, the signal enhancement circuit 205 amplifies the external input signal before superimposing the bias voltage to enhance the driving capability of the signal and further reduce the distortion of the signal transmission process. At the same time, the first resistor is set in the signal enhancement circuit to ensure that the first operator amplifies the signal without distortion.

[0064] In this embodiment, the signal superposition circuit 204 is an adder circuit composed of operational amplifiers or a subtractor circuit composed of operational amplifiers.

[0065] This embodiment uses an adder and a subtractor to complete the superposition of the signal and the bias voltage, so that during the transmission of the signal, the MOS tube can ensure distortion-free transmission of the signal according to the superimposed bias voltage.

[0066] In this embodiment, refer to Figure 2 , also includes a signal amplifying circuit 206; the signal amplifying circuit 206 includes a second operational amplifier, a second resistor and a third resistor; wherein the second end of the first resistor and the output end of the signal superposition circuit 204 are respectively connected to the in-phase input end of the second operational amplifier, and the output end of the second operational amplifier is connected to the input end of the MOS tube; the third end of the second resistor and the fourth end of the third resistor are respectively connected to the inverting input end of the second operational amplifier; the fifth end of the second resistor is grounded, and the sixth end of the third resistor is connected to the output end of the second operational amplifier.

[0067] In this embodiment, the signal amplifying circuit 206 is configured to further amplify the superimposed signal to minimize distortion during signal transmission.

[0068] In this embodiment, the bias voltage providing circuit 203 includes a DAC and a fourth resistor; wherein the control end of the DAC is signal-connected to the main control unit 201, the output end of the DAC is connected to the seventh end of the fourth resistor; the eighth end of the fourth resistor is connected to the input end of the signal superposition circuit 204.

[0069] In this embodiment, the main control unit 201 controls the DAC to output a bias voltage to adjust the MOS tube to ensure that the MOSFET operates in a linear region. Furthermore, the fourth resistor is set in the bias voltage providing circuit to adjust the bias current of the MOSFET to improve the stability of the MOSFET operating in the linear region.

[0070] In this embodiment, the main control unit 201 determines the first bias voltage according to the comparison result between the gate voltage and the gate threshold voltage; the main control unit 201 determines the bias voltage output by the DAC according to the first bias voltage and the resistance values ​​corresponding to the first resistor, the second resistor, the third resistor, and the fourth resistor; wherein the calculation formula corresponding to the bias voltage is:

[0071] V DAC =V OS *(R 1 +R 4 ) / R 1 *(1+R 3 / R 2 )

[0072] Among them, the V DACrepresents the bias voltage of the DAC output; the V OS represents the first bias voltage determined by the main control unit; the R 1 represents the first resistor; the R 2 represents the second resistor; the R 3 represents the third resistor; the R 4 represents the fourth resistor.

[0073] In this embodiment, after the first bias voltage required by the MOS tube is determined by the main control unit 201, in order to ensure that the voltage output by the DAC can accurately control the MOS tube to operate in a linear range, the bias voltage output by the DAC is determined according to the resistance in the circuit and the first bias voltage, so that the MOS tube operates in a linear range according to the bias voltage output by the DAC, so that the signal can be output without distortion.

[0074] The present embodiment discloses a signal transmission method and circuit based on a MOS tube, which generates a bias voltage corresponding to the MOS tube by acquiring temperature information of the MOS tube, so that the bias voltage generated according to the temperature of the MOS tube can compensate for the temperature drift of the gate threshold voltage of the MOS tube, thereby improving the accuracy of the generated bias voltage, and then superimposing the generated bias voltage on an external input signal, and inputting the superimposed signal generated after superposition into the MOS tube, so as to control the MOS tube to work in a linear range according to the precise bias voltage in the superimposed signal, so that the signal is not distorted when it is output through a MOSFET, thereby reducing the distortion of the signal during transmission.

[0075] Embodiment 2

[0076] In the prior art, since different MOSFETs need to be provided with bias voltages of different magnitudes in order to operate in a linear range, when the MOSFET in the circuit changes, it is often necessary to change the electrical components in the circuit to provide the MOSFET with bias voltages of different magnitudes. At the same time, since the gate threshold voltage of the MOSFET is prone to temperature drift when the MOSFET is in operation, the bias voltage provided by the circuit does not meet the bias voltage actually required by the MOSFET, and thus it is impossible to ensure that the MOSFET is stably in the linear operating range.

[0077] In order to solve the above technical problems, this embodiment discloses a bias circuit that provides an adjustable bias voltage for the MOSFET based on the temperature of the MOSFET, and is used to provide a bias voltage that can compensate for the temperature drift when the gate threshold voltage of the MOSFET undergoes temperature drift.

[0078] In one implementation of this embodiment, refer to Figure 3 , is a schematic diagram of a bias circuit for providing an adjustable bias voltage to a MOSFET, wherein the bias circuit includes a microcontroller 301 , a temperature sensor circuit 302 , and a DAC circuit 303 .

[0079] Reference Figure 3 The microcontroller 301 is signal-connected to the temperature sensor 302 , and the temperature sensor circuit 302 is connected to or installed on the MOSFET, and is used to collect temperature information on the MOSFET and send the temperature information to the microcontroller 301 .

[0080] The output end of the microcontroller 301 is connected to the input end of the DAC circuit 303 , and is used to determine the bias voltage output by the DAC circuit 303 according to the temperature information sent by the temperature sensor circuit 302 .

[0081] The output end of the DAC circuit 303 is connected to the input end of the MOSFET, and is used to provide the bias voltage to the MOSFET, so as to control the MOSFET to operate in a linear range.

[0082] Specifically, in this embodiment, in the process of driving the DAC circuit 303 to output the bias voltage according to the temperature information sent by the temperature sensor circuit 302, in order to ensure that the bias voltage output by the DAC circuit 303 can compensate the gate threshold voltage of the MOSFET for temperature, the microcontroller 301 controls the DAC circuit 303 to first give an initial bias voltage value by comparing the Vgs threshold voltage of the MOS tube under normal temperature (25°C). During operation, the temperature sensor circuit 302 detects the temperature of the MOS tube in real time and transmits the temperature data back to the microcontroller 301. The microcontroller 301 compares the relationship curve between the temperature of the MOS tube and the Vgs threshold voltage (this relationship is in the MOS tube data manual) to adjust the bias voltage output by the DAC circuit 303 in real time according to the comparison result, so that the bias voltage can compensate the gate threshold voltage of the MOS tube for temperature. Furthermore, in the process of determining the bias voltage, the MOSFET will only begin to enter the linear region or the saturation region when the gate voltage is higher than the Vgs threshold voltage, otherwise it will be in the cut-off region. When the MOSFET enters the cut-off and saturation intervals, the amplified signal will be distorted. Therefore, the microcontroller 301 will determine the bias voltage required for the MOS tube based on the comparison result between the gate voltage and the gate threshold voltage, and then use the required bias voltage and the connection status of the DAC circuit 303 and the MOS tube to determine the bias voltage output by the DAC circuit 303, thereby ensuring that the MOSFET is in the linear region.

[0083] In this embodiment, different bias voltages are provided by the microcontroller 301 and the DAC circuit 303, which can not only compensate for the temperature drift of the Vgs threshold voltage (gate threshold voltage) of the MOSFET, but also can change different bias DC voltages by controlling the output of the DAC circuit 303 through the microcontroller 301 when replacing other types of MOSFETs, without replacing the electrical components of the circuit.

[0084] Furthermore, in order to ensure the stable operation of the MOSFET, the DAC circuit 303 is configured to output an adjustable DC bias voltage.

[0085] Furthermore, in certain implementations of this embodiment, the microcontroller 301 can be replaced by a host computer that can implement a temperature compensation algorithm for calculating the bias voltage output by the DAC circuit, DAC driving and information collection, and then communicate with the DAC circuit 303 through the host computer to change the DAC output voltage value.

[0086] The bias circuit provided in this embodiment controls the DAC to provide a bias voltage for the MOSFET and collects temperature sensor data through the microcontroller 301 to adjust the bias voltage output by the DAC, so that the bias voltage output by the DAC can perform temperature compensation on the gate threshold voltage of the MOSFET, so that the MOSFET can work better in the linear region.

[0087] In some application scenarios of this embodiment, refer to Figure 3 The bias circuit provided realizes signal transmission to ensure that when the signal is transmitted through the MOS tube, the MOS tube is controlled to operate in a linear region according to the bias voltage provided by the bias circuit, thereby reducing distortion of the signal when it is output through the MOS tube.

[0088] Specifically, refer to Figure 4 , for some implementations of this embodiment according to Figure 3 The signal transmission circuit provided by the bias circuit for signal transmission includes an operational amplifier circuit 401 , an operational amplifier circuit 402 , a microcontroller 301 , a temperature sensor circuit 302 and a DAC circuit 303 .

[0089] Reference Figure 4 The output end of the operational amplifier circuit 401 is connected to the input end of the operational amplifier circuit 402, for receiving an external input signal, amplifying the signal to improve the driving capability of the signal, and sending the amplified signal to the operational amplifier circuit 402.

[0090] The output end of the operational amplifier circuit 402 is connected to the GATE end of the MOSFET, and the input end thereof is also connected to the output end of the DAC circuit 303, for receiving the amplified signal and the bias voltage provided by the DAC circuit 303, and superimposing the bias voltage with the amplified signal to send the generated superimposed signal to the MOSFET, thereby allowing the input signal to be output through the MOSFET.

[0091] In this embodiment, the input end of the operational amplifier circuit 401 is used to receive an arbitrary waveform signal input from the outside and amplify the signal to enhance the driving capability of the external input signal and prevent attenuation or distortion during back-end processing. Furthermore, an input impedance can be added to the input end of the operational amplifier circuit 401 to provide a certain degree of isolation between the external input source and the internal circuit.

[0092] In this embodiment, the operational amplifier circuit 402 may be composed of an adder or subtractor circuit composed of operational amplifiers. After receiving the bias voltage and the amplified signal, it superimposes the signal with the bias voltage output by the DAC, superimposes the input signal on the bias voltage, and finally outputs the superimposed signal to the gate of the MOS tube, so that the signal is amplified without distortion.

[0093] In this embodiment, based on the fact that the operational amplifier circuit 402 is used to perform signal superposition and the operational amplifier circuit 401 is used to perform signal amplification, in some implementations of this embodiment, electrical components such as an inverting adder, a non-inverting adder, a non-inverting amplifier, and an inverting amplifier may be used to implement the above functions.

[0094] In a certain implementation manner of this embodiment, a common-phase adder is used to form the operational amplifier circuit 402 to perform signal superposition, and a common-phase amplifier is used to form the operational amplifier circuit 401 to achieve signal amplification.

[0095] Specifically, refer to Figure 5 , is a circuit diagram of a certain implementation of this embodiment in which the in-phase adder, the in-phase amplifier, the DAC circuit, and the MOSFET are connected. The operational amplifier circuit 401 is composed of an operational amplifier U2 and a resistor R5, and is used to collect the external input signal and amplify the signal to generate a first signal; the input end of the operational amplifier U2 is used to receive the external input signal, and the output end of the operational amplifier U2 is connected to the first end of the resistor R5; the second end of the resistor R5 is connected to the input end of the operational amplifier circuit 402.

[0096] Reference Figure 5The DAC circuit 303 is provided with a DAC and a resistor R6, wherein the control end of the DAC is connected to the signal of the microcontroller 201, the output end of the DAC is connected to the seventh end of the resistor R6; and the eighth end of R6 is connected to the input end of the operational amplifier U1.

[0097] Reference Figure 5 After U2 outputs the amplified signal and the DAC outputs the bias voltage, the intersection of the DAC circuit 303 and the operational amplifier circuit 401 is determined, and a common-phase adder is set between the intersection and the operational amplifier U1 to superimpose the bias voltage and the signal through the common-phase adder to generate a superimposed signal.

[0098] Specifically, refer to Figure 5 , XFG1 is a signal generator. The signal output by XFG1 reaches the same-direction input terminal (PI N3) of the U2 operational amplifier and then is output from the output terminal (PI N6) of the U2 operational amplifier. The voltage output by the U2 operational amplifier passes through R5 and is superimposed with the voltage of the DAC through R6.

[0099] Furthermore, in order to ensure that the signal is as undistorted as possible when being output through the MOS tube, an operational amplifier may be provided between the in-phase adder and the MOS tube to amplify the superimposed signal. Figure 5 , an operational amplifier U1 is set, and the superimposed signal of the two is input to the same-direction input terminal (PI N3) of the operational amplifier U1, and the U1 operational amplifier then amplifies the superimposed signal by 2 times in the same direction and outputs it to the gate of the MOSFET. Among them, one end of the operational amplifier is respectively connected to R4 and R3, and the output end of the operational amplifier is respectively connected to R3 and the gate of the MOSFET.

[0100] Reference Figure 5 According to the circuit shown in FIG. 1 , after the microcontroller 301 determines the bias voltage required by the MOS tube, the calculation formula of the voltage output by the DAC circuit 303 is:

[0101] V DAC =V OS *(R 5 +R 6 ) / R 5 *(1+R 3 / R 4 )

[0102] The present embodiment discloses a bias circuit and a signal transmission circuit, wherein an arbitrary waveform signal can be input into the signal transmission circuit, and the output end of the signal transmission circuit is connected to the GATE of the MOSFET. The microcontroller 301 can be used to control the DAC to adjust the GATE terminal voltage of the MOSFET and collect temperature sensor data for temperature compensation, so that the MOSFET can work better in the linear region and the output signal can be distorted as little as possible.

[0103] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A signal transmission method based on MOS tube, characterized in that: include: Acquiring temperature information of the MOS tube to generate a bias voltage corresponding to the MOS tube; Superimposing the bias voltage with an external input signal to generate a superimposed signal; The superimposed signal is input to the MOS tube, and the signal is transmitted through the MOS tube.

2. A signal transmission method based on MOS tube according to claim 1, characterized in that: The acquiring temperature information of the MOS tube to generate a bias voltage corresponding to the MOS tube includes: Obtaining a temperature and gate threshold voltage relationship table corresponding to the MOS tube; According to the temperature information, query the temperature and gate threshold voltage relationship table to obtain the gate threshold voltage corresponding to the temperature information; A gate voltage corresponding to the MOS tube is obtained, and the gate voltage is compared with the gate threshold voltage to determine a bias voltage corresponding to the MOS tube according to a result of the comparison.

3. The signal transmission method based on MOS tube according to claim 1, characterized in that: The step of superimposing the bias voltage with an external input signal to generate a superimposed signal comprises: Collecting the signal input externally, and amplifying the signal to generate a first signal; The first signal is superimposed on the bias voltage to generate the superimposed signal.

4. A signal transmission circuit based on a MOS tube, characterized in that: It includes a main control unit, a temperature information acquisition unit, a bias voltage providing circuit, and a signal superposition circuit; The temperature information acquisition unit is connected to the main control unit by signal, and is used to obtain the temperature information of the MOS tube and send the temperature information to the main control unit; The main control unit is connected to the bias voltage providing circuit signal, and is used to control the bias voltage providing circuit to generate a bias voltage corresponding to the MOS tube according to the temperature information, and send the bias voltage to the signal superposition circuit; The input end of the signal superposition circuit is connected to the output end of the bias voltage providing circuit, and is used to receive the bias voltage and superimpose the bias voltage with an external input signal to generate a superimposed signal; The output end of the signal superposition circuit is connected to the input end of the MOS tube, and is used to input the superposition signal into the MOS tube, so as to complete the transmission of the signal through the MOS tube.

5. The signal transmission circuit based on MOS tube according to claim 4, characterized in that: The main control unit is also used to obtain a temperature and gate threshold voltage relationship table corresponding to the MOS tube; query the temperature and gate threshold voltage relationship table according to the temperature information to obtain the gate threshold voltage corresponding to the temperature information; obtain the gate voltage corresponding to the MOS tube, and compare the gate voltage with the gate threshold voltage to control the bias voltage providing circuit to generate the bias voltage corresponding to the MOS tube according to the comparison result.

6. The signal transmission circuit based on MOS tube according to claim 4, characterized in that: It also includes a signal enhancement circuit; the signal enhancement circuit includes a first operational amplifier and a first resistor, which are used to collect the external input signal and amplify the signal to generate a first signal; wherein the input end of the first operational amplifier is used to receive the external input signal, and the output end of the first operational amplifier is connected to the first end of the first resistor; the second end of the first resistor is connected to the input end of the signal superposition circuit.

7. The signal transmission circuit based on MOS tube according to claim 4, characterized in that: The signal superposition circuit is an adder circuit composed of operational amplifiers or a subtractor circuit composed of operational amplifiers.

8. The signal transmission circuit based on MOS tube according to claim 6, characterized in that: It also includes a signal amplification circuit; the signal amplification circuit includes a second operational amplifier, a second resistor and a third resistor; wherein the second end of the first resistor and the output end of the signal superposition circuit are respectively connected to the in-phase input end of the second operational amplifier, and the output end of the second operational amplifier is connected to the input end of the MOS tube; the third end of the second resistor and the fourth end of the third resistor are respectively connected to the inverting input end of the second operational amplifier; the fifth end of the second resistor is grounded, and the sixth end of the third resistor is connected to the output end of the second operational amplifier.

9. The signal transmission circuit based on MOS tube according to claim 7, characterized in that: The bias voltage providing circuit includes a DAC and a fourth resistor; wherein the control end of the DAC is connected to the main control unit signal, the output end of the DAC is connected to the seventh end of the fourth resistor; and the eighth end of the fourth resistor is connected to the input end of the signal superposition circuit.

10. A signal transmission circuit based on a MOS tube according to any one of claims 5 to 9, characterized in that: The main control unit determines a first bias voltage according to a comparison result between the gate voltage and the gate threshold voltage; The main control unit determines the bias voltage output by the DAC according to the first bias voltage and the resistance values ​​corresponding to the first resistor, the second resistor, the third resistor, and the fourth resistor; wherein the calculation formula corresponding to the bias voltage is: V DAC =V OS *(R1+R4) / R1*(1+R3 / R2) Among them, the V DAC represents the bias voltage of the DAC output; the V OS represents the first bias voltage determined by the main control unit; the R1 represents the first resistor; the R2 represents the second resistor; the R3 represents the third resistor; and the R4 represents the fourth resistor.

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