CN212965789U - I2C communication circuit, numerical control voltage signal output device - Google Patents

Abstract

The utility model provides a I²C communication circuit, and numerical control voltage signal output device. Said I²C communication circuit including signal transmission serial port and I²A C logic control circuit; the signal transmission serial port is connected to a serial port of an upper computer; said I²The C logic control circuit is connected between the signal transmission serial port and the digital-to-analog converter; said I²The C logic control circuit is connected with a serial port of an upper computer through a signal transmission serial port to obtain a digital coding signal and transmits the digital coding signal to the digital-to-analog converter. In the numerical control voltage signal output device, the digital-to-analog converter passes through I²Voltage figure in voltage figure coding signal obtained by C communication circuitAnd after the codes are subjected to digital-to-analog conversion, corresponding voltage signals are output through the voltage output port. I of the utility model²The C communication circuit and the numerical control voltage signal output device have the advantages of simple circuit structure and high reliability.

Description

I2C communication circuit, digital control voltage signal output device

Technical Field

The utility model relates to a voltage output field especially relates to a I²C communication circuit, digital control voltage signal output device.

Background

In some applications that need the accurate output of control voltage, just need provide accurate voltage signal for the time of components and parts detection and display screen brightness control, if adopt the industrial control host computer control to output 0 ~ 5V voltage signal scheme, the serial ports through the host computer under general condition sends data for the singlechip, then by the accurate voltage signal of singlechip control peripheral circuit output. Therefore, the scheme of accurate voltage output needs to use a single chip microcomputer for transfer and also needs related peripheral circuits for matching, so that the problems of complex circuit structure and low reliability exist.

SUMMERY OF THE UTILITY MODEL

In order to overcome the problems existing in the related art, the embodiment of the utility model provides an I²The C communication circuit and the numerical control voltage signal output device are used for receiving the digital coding signal of the upper computer and outputting a corresponding electric signal, and the C communication circuit has the advantages of simple circuit structure and high reliability.

According to an aspect of the embodiments of the present invention, there is provided an I²C communication circuit including signal transmission serial port and I²A C logic control circuit; the signal transmission serial port is connected to a serial port of an upper computer; said I²The C logic control circuit is connected between the signal transmission serial port and the digital-to-analog converter; said I²The C logic control circuit is connected to a serial port of an upper computer through a signal transmission serial port to obtain a digital coding signal and transmit the digital coding signal to the digital-to-analog converter.

The embodiment of the utility model provides an I²And the communication circuit can be connected with a serial port of the upper computer for communication, acquires a digital coding signal and transmits the digital coding signal to the digital-to-analog converter for digital-to-analog conversion, so that the communication circuit is simplified and has higher reliability.

In an alternative embodiment, the I²The C logic control circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor and a switching tube; the first end of the first resistor is connected to the fourth pin of the signal transmission serial port, and the second end of the first resistor is connected to the serial communication data signal port of the digital-to-analog converter; the first end of the second resistor is connected to the ninth end of the signal transmission serial portThe second end of the pin is connected with the second end of the first resistor and is connected to a serial communication data signal port of the digital-to-analog converter together; the first end of the third resistor is connected to the seventh pin of the signal transmission serial port, and the second end of the third resistor is connected to the serial communication clock port of the digital-to-analog converter; the first end of the fourth resistor is connected to a ninth pin of the signal transmission serial port, and the second end of the fourth resistor is connected with the second end of the third resistor and is connected to a serial communication clock port of the digital-to-analog converter; the controlled end of the switch tube is connected with the second end of the first resistor and a serial communication data signal port of the digital-to-analog converter to obtain a conducting signal, the signal input end of the switch tube is connected to the first pin of the signal transmission serial port, and the signal output end of the switch tube is connected to the ninth pin of the signal transmission serial port.

In an optional embodiment, the switching tube is a P-channel MOS tube, and a gate of the P-channel MOS tube is connected to the second end of the first resistor and a serial communication data signal port of the digital-to-analog converter to obtain a conduction signal; and the source electrode of the P-channel MOS tube is connected to the ninth pin of the signal transmission serial port, and the drain electrode of the P-channel MOS tube is connected to the first pin of the signal transmission serial port.

According to another aspect of the embodiments of the present invention, there is provided a digital control voltage signal output device, including the above-mentioned I²C communication circuit and digital-to-analog converter; the digital-to-analog converter has a communication port and a voltage output port, and the communication port of the digital-to-analog converter passes through the I²The digital-to-analog converter performs digital-to-analog conversion on the voltage digital coding signal and outputs a corresponding voltage signal through the voltage output port.

In an alternative embodiment, the digital-to-analog converter has a power input port, a serial communication clock signal port, a serial communication data signal port and an analog voltage output port, the power input port is connected with the ninth pin of the signal transmission serial port to get power,the serial communication clock signal port passes through the I²A third resistor of the C logic control circuit is connected to a seventh pin of the signal transmission serial port, and the serial communication data signal port is used as a communication port of the digital-to-analog converter and passes through the I²The first resistor of the C logic control circuit is connected to the fourth pin of the signal transmission serial port and passes through the I²A switch tube of the C logic control circuit is connected to a first pin of the signal transmission serial port; the analog voltage output port is used as the voltage output port and outputs corresponding voltage signals.

In an alternative embodiment, the digital-to-analog converter further has a reference voltage input port; the digital-to-analog conversion circuit further comprises a reference voltage circuit; the reference voltage circuit comprises an adjustable precise voltage regulator tube, a fifth resistor and a first capacitor; the reference electrode of the adjustable precise voltage-stabilizing tube is connected with the reference voltage input port of the digital-to-analog converter and is connected to the ninth pin of the signal transmission serial port through a fifth resistor, the cathode of the adjustable precise voltage-stabilizing tube is connected with the reference electrode and is grounded through the first capacitor, and the anode of the adjustable precise voltage-stabilizing tube is grounded.

In an optional embodiment, the device further comprises a negative voltage generating circuit; the negative voltage generating circuit comprises a first diode, a second diode and a second capacitor; the negative electrode of the first diode is connected to a seventh pin of the signal transmission serial port; the cathode of the second diode is connected to the fourth pin of the signal transmission serial port, the anode of the second diode is connected with the anode of the first diode, and the second diode is connected to the first pin of the signal transmission serial port through the sixth resistor; and the connection nodes of the anode of the first diode, the anode of the second diode and the sixth resistor are grounded through the second capacitor.

In an optional embodiment, the digital-to-analog converter further comprises a voltage multiplying circuit connected to a voltage output port of the digital-to-analog converter; the voltage multiplication circuit comprises a first operational amplifier, a seventh resistor and an eighth resistor; the first operational amplifier is provided with a non-inverting input end, an inverting input end and an amplified signal output end, wherein the non-inverting input end is connected to a voltage output port of the digital-to-analog conversion circuit, the seventh resistor is connected between the inverting input end and the amplified signal output end in series, and the inverting input end is grounded through the eighth resistor.

In an optional embodiment, the digitally controlled voltage signal output device further comprises a boost circuit; the booster circuit is provided with a low-voltage input end and a high-voltage output end, the low-voltage input end of the booster circuit is connected to a ninth pin of the signal transmission serial port to obtain a low-voltage direct-current power supply, and the low-voltage direct-current power supply is boosted and then output to the power input port of the first operational amplifier from the high-voltage output end.

In an optional embodiment, the boost circuit includes a boost chip, a first inductor, a third diode, a third capacitor, a ninth resistor, and a tenth resistor; the boost chip is provided with a third power supply input port, an enabling trigger port, a voltage output control port, an overvoltage feedback port and an output voltage sampling port; a connection node of a third power input port of the boost chip and an enabling trigger port serves as a low-voltage input end of the boost circuit and is connected to a ninth pin of the signal transmission serial port to obtain electricity; the first inductor is connected between a third power input port and a voltage output control port of the boost chip in parallel; the anode of the third diode is connected to the voltage output control port of the boost chip, the cathode of the third diode is used as the high-voltage output end of the boost circuit, the third diode is grounded through the third capacitor, and the third diode filters a voltage signal output by the voltage output control port of the boost chip and outputs the voltage signal to the power input port of the first operational amplifier; the negative electrode of the third diode is connected to the output voltage sampling port of the boost chip through a ninth resistor, and the connection node of the ninth resistor and the output voltage sampling port of the boost chip is grounded through a tenth resistor; and an overvoltage feedback port of the boosting chip is grounded.

Use technical scheme, can follow the serial ports of host computer and obtain voltage digital code signal to carry out digital analog conversion with this voltage digital code signal through digital analog conversion circuit, final output accurate controllable voltage signal need not to use the singlechip to do the transfer, circuit structure is simple, and signal transmission route is short, low-power consumption and reliability height.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.

For a better understanding and an implementation, the present invention is described in detail below with reference to the accompanying drawings.

Drawings

FIG. 1 shows an embodiment of the present invention²C, an application schematic block diagram of the communication circuit;

fig. 2 is a schematic circuit diagram of a digital control voltage signal output device according to an embodiment of the present invention;

fig. 3 is a schematic connection diagram of a voltage multiplier circuit according to an embodiment of the present invention;

fig. 4 is a schematic connection diagram of a boost circuit according to an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the invention, as detailed in the appended claims.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, the first information may also be referred to as second information, and similarly, the second information may also be referred to as first information, without departing from the scope of the present invention.

Please refer to fig. 1, which shows an embodiment of the present invention²And C, an application schematic block diagram of the communication circuit.

As shown in fig. 1, the digital control voltage signal output device 20 of the present embodiment is connected to the industrial control upper computer 10 to obtain a digital coding signal, and performs digital-to-analog conversion on a voltage digital code carried by the digital coding signal to output an analog voltage signal to the voltage control device 30. The industrial control upper computer 10 comprises a processor 11 and a serial port 12 which are electrically connected with each other; the digital control voltage signal output device 20 comprises I which are electrically connected in sequence along the voltage signal flow direction²C communication circuits (21 and 22), and a digital-to-analog conversion circuit 23, wherein the I²The C communication circuit comprises a signal transmission serial port 21 and an I²C logic control circuit 22. The processor 11 of the upper computer 10 is connected with the signal transmission serial port 21 of the numerical control voltage signal output device 20 through the serial port 12, outputs a voltage digital coding signal to the digital-to-analog conversion circuit 23 of the numerical control voltage signal output device 20 for digital-to-analog conversion, and then outputs a voltage signal matched with a working power supply of the voltage control device 30 to the voltage control device 30, wherein the logic control circuit 22 is used for performing logic control of circuit switching. It should be noted that the voltage control device 30 in this embodiment may be a non-power type electric component or a back-end circuit, and is not limited herein.

According to a first aspect of the present invention, there is provided an I²C communication circuit including signal transmission serial port 21 and I²A C logic control circuit 22; the signal transmission serial port 21 is connected to the serial port 12 of the upper computer; said I²The C logic control circuit 22 is connected between the signal transmission serial port 21 and the digital-to-analog converter 23; said I²The C logic control circuit 22 is connected to the serial port 12 of the upper computer through the signal transmission serial port 21 to obtain the digital coding informationAnd transmitted to the digital-to-analog converter 23.

Said I²The C logic control circuit 22 comprises a first resistor R9, a second resistor R8, a third resistor R10, a fourth resistor R7 and a switching tube Q1; a first end of the first resistor R9 is connected to the fourth pin of the signal transmission serial port 21, and a second end thereof is connected to the serial communication data signal port SDA of the digital-to-analog converter 23; the first end of the second resistor R8 is connected to the ninth pin of the signal transmission serial port 21, and the second end of the second resistor R9 is connected to the second end of the first resistor R9 and is commonly connected to the serial communication data signal port SDA of the digital-to-analog converter 23; a first end of the third resistor R10 is connected to the seventh pin of the signal transmission serial port 21, and a second end thereof is connected to the serial communication clock port SCL of the digital-to-analog converter 23; a first end of the fourth resistor R7 is connected to a ninth pin of the signal transmission serial port 21, and a second end of the fourth resistor R7 is connected to a second end of the third resistor R10 and commonly connected to the serial communication clock port SCL of the digital-to-analog converter 23; the controlled end of the switching tube Q1 is connected to the second end of the first resistor R9 and the serial communication data signal port SDA of the digital-to-analog converter 23 to obtain a conducting signal, the signal input end of the switching tube Q1 is connected to the first pin of the signal transmission serial port 21, and the signal output end of the switching tube Q1 is connected to the ninth pin of the signal transmission serial port 21. The switching tube Q1 is a PMOS tube.

The embodiment of the utility model provides an I²The communication circuit is connected to the upper computer through a serial port, can obtain a voltage digital coding signal from the serial port of the upper computer and transmit the voltage digital coding signal to the digital-to-analog converter so as to perform digital-to-analog conversion on the voltage digital coding signal, and finally outputs an accurate analog voltage signal to be used as a control signal source of the voltage control equipment.

In other embodiments, the I²The C communication circuit can also be applied to control the output of precise current for other equipment or I²And the sensor C is used for facilitating the upper computer to acquire a sensing signal.

According to the utility model discloses a second aspect provides a numerical control voltage signal output device for export accurate voltage signal.

Referring to fig. 2, fig. 2 is a schematic circuit diagram of a digital control voltage signal output device according to an embodiment of the present invention.

The digital-to-analog conversion circuit 23 has a communication port and a voltage output port, and the communication port of the digital-to-analog conversion circuit 23 passes through the I²The C logic control circuit 22 and the signal transmission serial port 21 are connected to the serial port 11 of the upper computer 10 to obtain a voltage digital coding signal, and the digital-to-analog conversion circuit 23 performs digital-to-analog conversion on the voltage digital coding signal and outputs a corresponding analog voltage signal through the signal output port.

In an alternative embodiment, the digital-to-analog conversion circuit 23 includes a digital-to-analog converter, which may be a digital-to-analog conversion chip U1, and the type of the digital-to-analog converter is not limited as long as the digital-to-analog converter can convert the digital voltage coded signal of the digital quantity into the digital voltage signal of the analog quantity, and the precision and the characteristics are satisfactory. The digital-to-analog converter U1 has a first power input port VDD, a serial communication clock signal port SCL, a serial communication data signal port SDA, an analog voltage output port VOUT, and a reference voltage input port VREF. The working voltage of the digital-to-analog converter U1 is obtained through a serial port of the upper computer 10, the first power input port VDD is connected with a ninth pin of the signal transmission serial port 21 to obtain power, and the power ground terminal VSS is connected with a fifth pin of the signal transmission serial port 21 and grounded.

The serial communication clock signal port SCL is connected to the seventh pin of the signal transmission serial port 21 through the logic control circuit 22, and the serial communication data signal port SDA is used as the communication port of the digital-to-analog conversion circuit 23 and is connected to the fourth pin and the first pin of the signal transmission serial port 21 through the logic control circuit 22; the analog voltage output port VOUT serves as a voltage output port of the digital-to-analog conversion circuit 23; the digital-to-analog converter U1 receives a voltage digital coding signal of an upper computer through a serial communication data signal port SDA, and outputs a voltage signal corresponding to a controlled source of the voltage-controlled equipment from the analog voltage output port VOUT after digital-to-analog conversion.

In an alternative embodiment, the digital-to-analog converter U1 may use a 12-bit MCP4726 chip with an EEPROM, and the corresponding voltage value can be output as long as the chip is powered on, so that the circuit does not have a problem of dead halt, and the reliability is higher than that of the single chip microcomputer scheme in the prior art. In addition, the digital-to-analog converter U1 may also be a 10-bit MCP4716 chip or an 8-bit MCP4706 chip.

In an alternative embodiment, the logic control circuit 22 is I²And the C logic control circuit is used for realizing level matching and half-duplex control. Said I²The C logic control circuit comprises a first resistor R9, a second resistor R8, a third resistor R10, a fourth resistor R7 and a switching tube Q1; the serial communication data signal port SDA of the digital-to-analog converter U1 is connected to the fourth pin of the signal transmission serial port 21 through the first resistor R9, and is connected to the ninth pin of the signal transmission serial port 21 through a pull-up resistor, that is, the second resistor R8, and the serial communication clock signal port SCL of the digital-to-analog converter U1 is connected to the seventh pin of the signal transmission serial port 21 through the third resistor R10, and is connected to the ninth pin of the signal transmission serial port 21 through a pull-up resistor, that is, the fourth resistor R7; the gate G of the switch tube Q1 is connected with one end of the first resistor R9 and the serial communication data signal port SDA of the digital-to-analog converter U1 to obtain a conducting signal, the source S of the switch tube Q1 is connected with the first power input port VDD of the digital-to-analog converter U1 and the ninth pin of the signal transmission serial port 21, and the drain D of the switch tube Q1 is connected with the first pin of the signal transmission serial port 21. The resistance of the first resistor R9 may be 2K, the resistance of the second resistor R8, the resistance of the fourth resistor R7 may be 10K ohms, and the resistance of the third resistor R10 may be 5K ohms. The switching tube Q1 may be a P-channel MOS tube.

When the upper computer 10 sends a voltage digital code signal to the digital-to-analog conversion circuit 22 through the serial port, an 8-bit character string data code is sent, and the digital-to-analog converter U1 converts the character string data code into an analog voltage signal for output. The upper computer is connected to the digital-analog module through a seventh pin of the serial portThe serial communication clock signal port SCL of the converter U1 is connected to the serial communication data signal port SDA of the digital-to-analog converter U1 through the first resistor R9 via the fourth pin of the serial port. When the SDA of the digital-to-analog converter needs to respond or send data, the grid electrode of the PMOS tube is controlled to output inverted data to the first pin of the serial port, so that the upper computer can carry out I operation on the digital-to-analog converter²C, communication, reading or setting related parameters and output voltage values.

The digital-to-analog conversion circuit 23 further includes a reference voltage circuit; the reference voltage reference circuit comprises an adjustable precision voltage regulator tube U2, a fifth resistor R6 and a first capacitor C3; a reference pole R of the adjustable precision voltage regulator tube U2 is connected with a reference voltage input port VREF of the digital-to-analog converter U1, and is connected to a ninth pin of the signal transmission serial port 21 through a fifth resistor R6 to obtain a power supply, a cathode of the adjustable precision voltage regulator tube U2 is connected with the reference pole R, and is grounded through the first capacitor C3, and an anode of the adjustable precision voltage regulator tube U2 is grounded.

In the reference voltage reference circuit, an adjustable precise voltage regulator tube U2 provides a stable 2.50V reference voltage for a digital-to-analog converter U1, so that the digital-to-analog converter outputs a correct voltage value. The model of the adjustable precise voltage-regulator tube U2 can be TL431, the conducting voltage is 2.50V, when the voltage of the reference electrode R is more than 2.50V, the operational amplifier unit in the adjustable precise voltage-regulator tube U2 is conducted, current flows from the cathode K to the anode A, and the voltage value of the cathode K can not change greatly at the moment, so that the voltage-stabilizing effect is achieved.

In an alternative embodiment, only the positive voltage is provided to the ninth pin of the signal transmission serial port 21, but the first pin of the signal transmission serial port 21 needs to be driven by the negative voltage. Therefore, the numerical control voltage signal output device also comprises a negative voltage generating circuit; the negative voltage generating circuit comprises a first diode D1, a second diode D2 and a second capacitor C1; the negative electrode of the first diode D1 is connected to the seventh pin of the signal transmission serial port 21 to obtain power; the cathode of the second diode D2 is connected to the fourth pin of the signal transmission serial port 21 for power supply, the anode thereof is connected to the anode of the first diode D1, a negative voltage is formed at the second capacitor C1, and the second diode D2 is connected to the first pin of the signal transmission serial port 21 through the sixth resistor R11. The connection node of the anode of the first diode D1, the anode of the second diode D2 and the sixth resistor R11 is grounded through the second capacitor C1. The sixth resistor R11 is a pull-down resistor with a resistance of 5K ohms.

Referring to fig. 3, fig. 3 is a schematic diagram of a voltage multiplier circuit according to an embodiment of the present invention.

In an alternative embodiment, the digitally controlled voltage signal output device 20 further includes a voltage multiplication circuit connected to the signal output port of the digital-to-analog conversion circuit 23, i.e. to the voltage output port Vout of the digital-to-analog converter U1, for multiplying the voltage of the voltage signal at the voltage output port Vout of the digital-to-analog converter U1 to be suitable for more voltage-controlled devices.

Specifically, the voltage multiplication circuit comprises a first operational amplifier U3, a seventh resistor R12 and an eighth resistor R11; the first operational amplifier U3 has a non-inverting input terminal, an amplified signal output terminal, and a power input port, wherein the non-inverting input terminal is connected to the voltage output port of the digital-to-analog conversion circuit 23, the seventh resistor R12 is connected in series between the inverting input terminal and the amplified signal output terminal, and the inverting input terminal is grounded through the eighth resistor R11. The resistance values of the seventh resistor R12 and the eighth resistor R11 are equal and may be 5K ohms. When the voltage output port Vout of the digital-to-analog conversion circuit 23 outputs 5V voltage, the amplified signal output terminal may output 10V voltage; when the voltage output port Vout of the digital-to-analog conversion circuit 23 outputs a voltage of 0 to 5V, the amplified signal output port may output a multiplied voltage of 0 to 10V.

In other embodiments, the voltage multiplier circuit may also adopt other circuit structures.

Referring to fig. 4, fig. 4 is a schematic diagram of a connection of a boost circuit according to an embodiment of the present invention.

Since the power supply input port of the first operational amplifier U3 of the voltage multiplier circuit needs a voltage source of +12V, and the voltage source of the serial port output is +5V, a voltage boost circuit is also needed to boost the voltage source of +5V to a voltage source of + 12V.

In an alternative embodiment, the voltage boost circuit has a low voltage input terminal and a high voltage output terminal, the low voltage input terminal of the voltage boost circuit is connected to the ninth pin of the signal transmission serial port 21 to obtain a +5V dc power, the voltage of the +5V dc power is boosted to +12V and then output from the high voltage output terminal to the power input port of the first operational amplifier U3, and the first pin of the first operational amplifier U3, and the 2 nd pin of the first operational amplifier U3 is grounded.

In an optional embodiment, the boost circuit includes a boost chip U4, a first inductor L1, a third diode D3, a third capacitor C5, a ninth resistor R13, and a tenth resistor R14; the booster chip U4 may be of a MIC2619 type and has a third power input port VIN, an enable trigger port EN, a voltage output control port SW, an overvoltage feedback port OVP and an output voltage sampling port FB; a connection node of a third power input port of the boost chip and an enabling trigger port serves as a low-voltage input end of the boost circuit and is connected to a ninth pin of the signal transmission serial port to obtain electricity; the first inductor is connected between a third power input port and a voltage output control port of the boost chip in parallel; the anode of the third diode D3 is connected to the SW port of the boost chip, and the cathode thereof is used as the high voltage output end of the boost circuit and is grounded through the third capacitor C5. The third diode D3 may be a schottky diode. The cathode of the third diode D3 is connected to the output voltage sampling port of the boost chip through a ninth resistor R13, and the connection node of the ninth resistor R13 and the output voltage sampling port of the boost chip is grounded through a tenth resistor R14; and an overvoltage feedback port OVP of the boost chip is grounded. After the voltage of +5V is increased to +12V by the voltage boosting chip U4, the voltage is regulated and output through a voltage stabilizing diode, namely a third diode D3, the first inductor L1 plays a role in energy storage and voltage boosting, and the third diode D3 plays a role in continuous flow. In addition, the voltage sampling port FB of the boost chip U4 can feed back the sampling signal of the output voltage, so that the output voltage is stabilized at + 12V.

The embodiment of the utility model provides a numerical control voltage signal output device, can follow the serial ports of host computer and obtain voltage digital code signal to carry out digital analog conversion with this voltage digital code signal through digital analog conversion circuit, the accurate controllable analog voltage signal of final output need not to use the singlechip to do the transfer, circuit structure is simple, and signal transmission path is short, low power dissipation and reliability are high. The power supplies required by all parts of the circuits of the numerical control voltage signal output device are all from the serial ports of the upper computer, and no external power supply is needed, so that the circuit structure is further simplified, and the hardware cost is reduced. Meanwhile, the digital-to-analog converter can output a voltage signal after being electrified, the problem of halt does not exist, and the reliability of the circuit is further improved. In addition, the digital-to-analog conversion chip can adopt 8 bits, 10 bits and 12 bits to adapt to the application of different voltage accuracies.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention.

Claims (10)

1. I²C communication circuit, characterized in that, it comprises signal transmission serial port and I²A C logic control circuit; the signal transmission serial port is connected to a serial port of an upper computer; said I²The C logic control circuit is connected between the signal transmission serial port and the digital-to-analog converter; said I²The C logic control circuit is connected to a serial port of an upper computer through a signal transmission serial port to obtain a digital coding signal and transmit the digital coding signal to the digital-to-analog converter.

2. The I of claim 1²C communication circuit, characterized in that I²The C logic control circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor and a switching tube; the first end of the first resistor is connected to the fourth pin of the signal transmission serial portTwo ends of the serial communication data signal port are connected to the digital-to-analog converter; the first end of the second resistor is connected to the ninth pin of the signal transmission serial port, and the second end of the second resistor is connected with the second end of the first resistor and is connected to the serial communication data signal port of the digital-to-analog converter; the first end of the third resistor is connected to the seventh pin of the signal transmission serial port, and the second end of the third resistor is connected to the serial communication clock port of the digital-to-analog converter; the first end of the fourth resistor is connected to a ninth pin of the signal transmission serial port, and the second end of the fourth resistor is connected with the second end of the third resistor and is connected to a serial communication clock port of the digital-to-analog converter; the controlled end of the switch tube is connected with the second end of the first resistor and a serial communication data signal port of the digital-to-analog converter to obtain a conducting signal, the signal input end of the switch tube is connected to the first pin of the signal transmission serial port, and the signal output end of the switch tube is connected to the ninth pin of the signal transmission serial port.

3. I according to claim 2²The communication circuit is characterized in that the switching tube is a P-channel MOS tube, and a grid electrode of the P-channel MOS tube is connected with the second end of the first resistor and a serial communication data signal port of the digital-to-analog converter to obtain a conducting signal; and the source electrode of the P-channel MOS tube is connected to the ninth pin of the signal transmission serial port, and the drain electrode of the P-channel MOS tube is connected to the first pin of the signal transmission serial port.

4. A numerically controlled voltage signal output device, comprising I according to any one of claims 1 to 3²C, a communication circuit and a digital-to-analog conversion circuit; the digital-to-analog conversion circuit is provided with a communication port and a voltage output port, and the communication port of the digital-to-analog conversion circuit passes through the I²The digital-to-analog conversion circuit performs digital-to-analog conversion on the voltage digital coding signal and outputs a corresponding voltage signal through the voltage output port.

5. The digitally controlled voltage signal output device according to claim 4, wherein said digital to analog conversion circuit comprises a digital to analog converter; the digital-to-analog converter is provided with a power supply input port, a serial communication clock signal port, a serial communication data signal port and an analog voltage output port, the power supply input port is connected with a ninth pin of the signal transmission serial port to obtain power, and the serial communication clock signal port passes through the I²A third resistor of the C logic control circuit is connected to a seventh pin of the signal transmission serial port, and the serial communication data signal port is used as a communication port of the digital-to-analog converter and passes through the I²The first resistor of the C logic control circuit is connected to the fourth pin of the signal transmission serial port and passes through the I²A switch tube of the C logic control circuit is connected to a first pin of the signal transmission serial port; the analog voltage output port is used as the voltage output port and outputs corresponding voltage signals.

6. The digitally controlled voltage signal output device according to claim 5, wherein said digital to analog converter further has a reference voltage input port; the digital-to-analog conversion circuit further comprises a reference voltage circuit; the reference voltage circuit comprises an adjustable precise voltage regulator tube, a fifth resistor and a first capacitor; the reference electrode of the adjustable precise voltage-stabilizing tube is connected with the reference voltage input port of the digital-to-analog converter and is connected to the ninth pin of the signal transmission serial port through a fifth resistor, the cathode of the adjustable precise voltage-stabilizing tube is connected with the reference electrode and is grounded through the first capacitor, and the anode of the adjustable precise voltage-stabilizing tube is grounded.

7. The digitally controlled voltage signal output device of claim 5, further comprising a negative voltage generating circuit; the negative voltage generating circuit comprises a first diode, a second capacitor and a sixth resistor; the negative electrode of the first diode is connected to a seventh pin of the signal transmission serial port; the cathode of the second diode is connected to the fourth pin of the signal transmission serial port, the anode of the second diode is connected with the anode of the first diode, and the second diode is connected to the first pin of the signal transmission serial port through the sixth resistor; and the connection nodes of the anode of the first diode, the anode of the second diode and the sixth resistor are grounded through the second capacitor.

8. The digitally controlled voltage signal output device of claim 4, further including a voltage multiplier circuit connected to a voltage output port of said digital to analog converter; the voltage multiplication circuit comprises a first operational amplifier, a seventh resistor and an eighth resistor; the first operational amplifier is provided with a non-inverting input end, an inverting input end and an amplified signal output end, wherein the non-inverting input end is connected to a voltage output port of the digital-to-analog conversion circuit, the seventh resistor is connected between the inverting input end and the amplified signal output end in series, and the inverting input end is grounded through the eighth resistor.

9. The digitally controlled voltage signal output device of claim 8, further including a boost circuit; the booster circuit is provided with a low-voltage input end and a high-voltage output end, the low-voltage input end of the booster circuit is connected to a ninth pin of the signal transmission serial port to obtain a low-voltage direct-current power supply, and the low-voltage direct-current power supply is boosted and then output to the power input port of the first operational amplifier from the high-voltage output end.

10. The digitally controlled voltage signal output device of claim 9, wherein said boost circuit comprises a boost chip, a first inductor, a third diode, a third capacitor, a ninth resistor and a tenth resistor; the boost chip is provided with a third power supply input port, an enabling trigger port, a voltage output control port, an overvoltage feedback port and an output voltage sampling port; a connection node of a third power input port of the boost chip and an enabling trigger port serves as a low-voltage input end of the boost circuit and is connected to a ninth pin of the signal transmission serial port to obtain electricity; the first inductor is connected between a third power input port and a voltage output control port of the boost chip in parallel; the anode of the third diode is connected to the voltage output control port of the boost chip, the cathode of the third diode is used as the high-voltage output end of the boost circuit, the third diode is grounded through the third capacitor, and the third diode filters a voltage signal output by the voltage output control port of the boost chip and outputs the voltage signal to the power input port of the first operational amplifier; the negative electrode of the third diode is connected to the output voltage sampling port of the boost chip through a ninth resistor, and the connection node of the ninth resistor and the output voltage sampling port of the boost chip is grounded through a tenth resistor; and an overvoltage feedback port of the boosting chip is grounded.

Images