CN217543222U

CN217543222U - Digital high-voltage meter with high input impedance

Info

Publication number: CN217543222U
Application number: CN202220926468.3U
Authority: CN
Inventors: 巫伟武
Original assignee: Guangzhou Deken Electronics Co ltd
Current assignee: Guangzhou Deken Electronics Co ltd
Priority date: 2022-04-20
Filing date: 2022-04-20
Publication date: 2022-10-04
Anticipated expiration: 2032-04-20

Abstract

The utility model discloses a high input impedance's digital high-voltage meter, including power supply circuit, measuring circuit, control circuit, decay circuit and voice circuit, power supply circuit supplies power for control circuit, measuring circuit and voice circuit respectively, and the decay circuit is used for inserting the high-voltage signal of external input to attenuate high-voltage signal with preset attenuation multiple, output the weak current signal after the decay to measuring circuit; the measuring circuit is used for measuring weak current signals to obtain measuring signals and sending the measuring signals to the control circuit, and the control circuit is used for restoring the measuring signals into high-voltage data according to preset attenuation multiples. It is through setting up decay circuit for the high-tension electricity signal is attenuated through decay circuit earlier, then inserts and carries out the measurement of size to the signal after the circuit measuring signal pair decay again, can realize high input impedance, and the linearity is good, and the stability is high, and the embodiment has still increased voice circuit, possesses voice prompt and reports the function, and the operation is more humanized.

Description

Digital high-voltage meter with high input impedance

Technical Field

The utility model relates to a circuit measurement technical field, concretely relates to high input impedance's digital high-voltage meter.

Background

The high-voltage meter is used for measuring industrial frequency AC high voltage and DC high voltage in power system and electric and electronic equipment manufacturing departments, and is generally composed of a high-voltage measuring part and a low-voltage display instrument, wherein the high-voltage part and the low-voltage instrument are separated during working, and the working is safe and reliable. The high-voltage meter is also called an AC/DC resistance-capacitance voltage divider, an AC voltage divider, a DC voltage divider, an AC/DC high-voltage testing device, a resistance-capacitance type DC voltage divider, an AC/DC resistance-capacitance voltage divider, an AC/DC digital voltage divider, a kilovolt voltmeter, a kilovolt meter, an FRC type AC/DC dual-purpose voltage divider, a high-voltage digital meter, a voltage divider, a resistance-capacitance voltage divider, an electrostatic voltmeter, a high-voltage divider and the like.

With the continuous development and popularization of the modern electronic technology, the safety problem of high-voltage work exists all the time, and meanwhile, the high voltage also has certain interference on the numerical value display of an instrument, so that the accuracy and the stability of the digital high-voltage meter are influenced.

Disclosure of Invention

In order to overcome the defects of the prior art, the utility model aims to provide a digital high-voltage meter with high input impedance, which attenuates high-voltage signals by setting an attenuation circuit and realizes the characteristics of high input impedance.

The purpose of the utility model is realized by adopting the following technical scheme:

the utility model provides a high input impedance's digital high-voltage meter, a serial communication port, including power supply circuit, measuring circuit, control circuit, decay circuit and voice circuit, power is supplied respectively for control circuit, measuring circuit and voice circuit to the power supply circuit, the decay circuit is connected with the measuring circuit, measuring circuit and voice circuit all with control circuit connection;

the attenuation circuit is used for accessing an externally input high-voltage electric signal, attenuating the high-voltage electric signal by a preset attenuation multiple, and outputting an attenuated weak electric signal to the measurement circuit; the measuring circuit is used for measuring the weak current signal to obtain a measuring signal and sending the measuring signal to the control circuit, and the control circuit is used for restoring the measuring signal into high-voltage data according to a preset attenuation multiple.

The utility model discloses in, as an optional embodiment, the decay circuit includes the first electric capacity of a plurality of, resistance R1, resistance R2, a plurality of connect gradually between the first electric capacity and form electric capacity series branch, the one end connecting resistance R2's of electric capacity series branch one end, the other end of electric capacity series branch are connected to between resistance R1 and the measuring circuit, and the high-tension electricity signal of outside input is inserted to resistance R1's one end and resistance R2's the other end.

The utility model discloses in, as an optional embodiment, first electric capacity includes electric capacity C01, electric capacity C02, electric capacity C03, electric capacity C04, electric capacity C05, electric capacity C06, electric capacity C07, electric capacity C08, electric capacity C09, electric capacity C010, electric capacity C011 and electric capacity C012, electric capacity C01, electric capacity C02, electric capacity C03, electric capacity C04, electric capacity C05, electric capacity C06, electric capacity C07, electric capacity C08, electric capacity C09, electric capacity C010, electric capacity C011 and electric capacity C012 connect gradually and form the electric capacity series branch road, electric capacity C01 keeps away from the one end of electric capacity C02 and connects resistance R2, electric capacity C012 keeps away from the one end of electric capacity C011 is connected to between resistance R1 and the measuring circuit.

The utility model discloses in, as an optional embodiment, measuring circuit is including measuring the singlechip chip, measuring interface circuit includes interface and bleeder circuit, bleeder circuit includes triode Q3, triode Q4, resistance R27, resistance R18, resistance R58, switch K2A and switch K2B, the one end of interface is connected R1's the other end, triode Q3's base is connected with triode Q4's base, triode Q3's collecting electrode with triode Q4's collecting electrode is connected, triode Q3's projecting pole is connected to through resistance R18 measure the singlechip chip, triode Q4's projecting pole ground connection, triode Q4's projecting pole is still connect switch K2A's one end, and switch K2A's the other end is connected the interface, resistance R27's one end is connected switch K2B's one end, switch K2B's the other end is connected to sliding resistance RV 6's slip end through resistance R58, resistance RV 6's stiff end is connected to the interface, resistance R27's the other end is connected and is measured the singlechip chip, resistance R58 is connected the other end of singlechip control chip, the singlechip control chip is connected.

In the present invention, as an optional embodiment, the model of the measurement single chip is DTM0660.

The utility model discloses in, as an optional embodiment, measuring circuit still includes buzzer circuit, buzzer circuit includes buzzer BZ1, buffer, the input of buffer is connected measure the singlechip chip, the buffer is still connected buzzer BZ1.

The utility model discloses in, as an optional embodiment, voice circuit includes voice interface, first audio amplifier chip, second audio amplifier chip, voice interface connection control circuit, first audio amplifier chip and second audio amplifier chip all with voice interface connects, first audio amplifier chip's model is LM386+, the model of second audio amplifier chip is LM386 +.

The utility model discloses in, as an optional embodiment, power supply circuit includes electric capacity C1, electric capacity C2, electric capacity C3, electric capacity C6, electric capacity C7, electric capacity C11, power chip T1, power chip T2, switch K8B and steady voltage chip, electric capacity C1 is connected with electric capacity C2 and is formed the series branch, the series branch is connected with external power source, electric capacity C3's one end and power chip T1's first input all with the one end of series branch is connected, electric capacity C3's the other end and power chip T2's second input all are connected with the other end of series branch, power chip T1's output passes through switch K8B and connects power chip T1's input, power chip T1's earthing terminal passes through electric capacity C6 and connects power chip T2's earthing, power chip T2's first output connects electric capacity C11's one end, power chip T2's second output and electric capacity C11's the other end all ground connection, steady voltage chip's input is connected power chip T2's input, steady voltage chip's earthing terminal is connected the output and the voice chip's output still through the measuring circuit, steady voltage chip 7 output.

In the present invention, as an optional embodiment, the model of the voltage stabilizing chip is HX7133, and the model of the power chip T2 is B0505S-1W.

In the present invention, as an optional embodiment, the control circuit includes a control chip, and the model of the control chip is 89C58-44.

Compared with the prior art, the beneficial effects of the utility model reside in that:

the utility model provides a high input impedance's digital high-voltage meter, it is through setting up the decay circuit for the high-voltage electricity signal attenuates through the decay circuit earlier, then inserts the measurement that carries out the size to the signal after the decay to the circuit measured signal again, can realize high input impedance, and the linearity is good, and the stability is high, and the embodiment has still increased voice circuit, possesses voice prompt and reports the function, and the operation is more humanized.

Drawings

Fig. 1 is a schematic diagram of a module structure of a digital high voltage meter with high input impedance according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a power supply circuit according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a measurement circuit according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a control circuit according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of an attenuation circuit according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a voice circuit according to an embodiment of the present invention.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and the detailed description, and it should be noted that the embodiments or technical features described below can be arbitrarily combined to form a new embodiment without conflict. Except as specifically noted, the materials and equipment used in this example are commercially available. Examples of embodiments are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present application. In the description of the present application, "a plurality" means two or more unless specifically stated otherwise.

In the description of the present application, it should be noted that unless otherwise specifically stated or limited, the terms "connected," "communicating," and "connected" are to be construed broadly, e.g., as meaning a fixed connection, a connection through an intervening medium, a connection between two elements, or an interaction between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as the case may be.

The terms "first," "second," and the like in the description and in the claims of the present application and in the above-described drawings are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The embodiment of the application provides a digital high-voltage meter of high input impedance, and it is through setting up decay circuit for the high-voltage signal of telecommunication attenuates through decay circuit earlier, then inserts and carries out the measurement of size to the signal after the decay to the circuit measured signal, can realize high input impedance, and the linearity is good, and the stability is high, and the embodiment has still increased voice circuit, possesses voice prompt and reports the function, and the operation is more humanized.

Referring to fig. 1, the digital high voltage meter with high input impedance according to the present embodiment includes a power circuit, a measurement circuit, a control circuit, an attenuation circuit, and a voice circuit, where the power circuit supplies power to the control circuit, the measurement circuit, and the voice circuit, respectively, the attenuation circuit is connected to the measurement circuit, and the measurement circuit and the voice circuit are both connected to the control circuit.

In the above, specifically, the attenuation circuit is configured to access an externally input high-voltage electrical signal, attenuate the high-voltage electrical signal by a preset attenuation multiple, and output an attenuated weak electrical signal to the measurement circuit; the measuring circuit is used for measuring the weak current signal to obtain a measuring signal and sending the measuring signal to the control circuit, and the control circuit is used for restoring the measuring signal into high-voltage data according to a preset attenuation multiple. The attenuation circuit is used for attenuating the high-voltage signal, the attenuation is stable, the temperature drift is low, the attenuated signal is accessed through the voltage division module in the measurement circuit for testing, the size of the attenuated signal is obtained, and the control circuit is used for restoring the real voltage data of the high-voltage electric signal.

Referring to fig. 2 to 6 specifically, the attenuation circuit in the embodiment includes a plurality of first capacitors, a resistor R1, and a resistor R2, where the first capacitors are sequentially connected to form a capacitor series branch, one end of the capacitor series branch is connected to one end of the resistor R2, the other end of the capacitor series branch is connected between the resistor R1 and the measurement circuit, and one end of the resistor R1 and the other end of the resistor R2 are connected to a high-voltage electrical signal input from outside.

The first capacitor may include 12 capacitors, in the schematic of fig. 5, the capacitors are respectively a capacitor C01, a capacitor C02, a capacitor C03, a capacitor C04, a capacitor C05, a capacitor C06, a capacitor C07, a capacitor C08, a capacitor C09, a capacitor C010, a capacitor C011 and a capacitor C012, the capacitors C01, C02, C03, C04, C05, C06, C07, C08, C09, C010, C011 and C012 are sequentially connected to form the capacitor series branch, one end of the capacitor C01 far away from the capacitor C02 is connected to the resistor R2, and one end of the capacitor C012 far away from the capacitor C011 is connected between the resistor R1 and the measurement circuit. In fact, one end of the capacitor C012, which is far away from the capacitor C011, is connected between the resistor R1 and the resistor R58 of the subsequent measurement circuit. In the attenuation circuit, after attenuation, a weak current signal of the high-voltage electric signal 1000 is obtained, and the weak current signal enters the measurement circuit through an interface of CN10 in the circuit to obtain measurement data. The control circuit sends a reading instruction to read the measurement data, and the measurement data is multiplied by the attenuation times to restore the real voltage data of the high-voltage electric signal.

In an embodiment, the measuring circuit includes a measuring monolithic chip, a measuring interface circuit, the measuring interface circuit includes an interface and a voltage dividing circuit, the voltage dividing circuit includes a triode Q3, a triode Q4, a resistor R27, a resistor R18, a resistor R58, a switch K2A and a switch K2B, one end of the interface is connected to the other end of the R1, the base of the triode Q3 is connected to the base of the triode Q4, the collector of the triode Q3 is connected to the collector of the triode Q4, the emitter of the triode Q3 is connected to the measuring monolithic chip through the resistor R18, the emitter of the triode Q4 is grounded, the emitter of the triode Q4 is further connected to one end of the switch K2A, the other end of the switch K2A is connected to the interface, one end of the resistor R27 is connected to one end of the switch K2B, the other end of the switch K2B is connected to the sliding end of the sliding resistor RV6 through the resistor R58, the fixed end of the resistor RV6 is connected to the interface, the other end of the resistor R27 is connected to the measuring monolithic chip, and the other end of the resistor R58 is connected to the monolithic chip, and the measuring circuit is connected to the measuring control chip.

The model of the measuring single chip microcomputer chip is preferably DTM0660. And the measuring single chip microcomputer chip is connected with the control circuit through a CS pin and an RDY pin. Furthermore, the measuring circuit further comprises a buzzer circuit, the buzzer circuit comprises a buzzer BZ1 and a buffer, the input end of the buffer is connected with the measuring single chip microcomputer chip, and the buffer is further connected with the buzzer BZ1. The type of the buffer can be selected as AT24C02, that is, U8 in fig. 3, and includes a pin A0, a pin A1, a pin A2, a VCC pin, a WP pin, an SCL pin, an SDA pin, and a GND pin, where the buffer is connected to the measurement single chip through the SCL pin and the SDA pin, and one end of the buzzer BZ1 is connected to the BZ pin of the measurement single chip. The buzzer circuit is also connected with the power circuit. Corresponding data broadcast can be carried out through the buzzer circuit, for example, the measured data measured by the measuring circuit can be subjected to voice broadcast through the buzzer circuit, or the alarm can be carried out through the buzzer circuit when the measured data is wrong.

Further, the embodiment further comprises a voice circuit, the voice circuit comprises a voice interface, a first audio amplification chip and a second audio amplification chip, the voice interface is connected with the control circuit, the first audio amplification chip and the second audio amplification chip are both connected with the voice interface, the model of the first audio amplification chip is LM386+, and the model of the second audio amplification chip is LM386 +. As shown IN FIG. 6, the voice interface is an interface CN2, an RX pin and a TX pin IN the interface CN2 are connected with a control circuit, a positive input end and a negative input end of the first audio amplifier chip are both connected with a 9 th interface of the interface CN2, a negative input end of the second audio amplifier chip is connected with a 9 th interface of the interface CN2, a positive input end of the second audio amplifier chip is connected with a 10 th interface of the interface CN2, the first audio amplifier chip and the second audio amplifier chip both have a GAIN pin, -IN pin, + IN pin, GND pin, BYP pin, VCC pin and VOUT pin, and both the first audio amplifier chip and the second audio amplifier chip are connected with a power supply circuit for supplying power.

Referring to fig. 2, the power circuit specifically includes a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C6, a capacitor C7, a capacitor C11, a power chip T1, a power chip T2, a switch K8B, and a voltage stabilizing chip, where the capacitor C1 is connected to the capacitor C2 to form a series branch, the series branch is connected to an external power supply, one end of the capacitor C3 and a first input end of the power chip T1 are both connected to one end of the series branch, the other end of the capacitor C3 and a second input end of the power chip T2 are both connected to the other end of the series branch, an output end of the power chip T1 is connected to an input end of the power chip T1 through the switch K8B, a ground end of the power chip T1 is connected to a ground end of the power chip T2 through the capacitor C6, a first output end of the power chip T2 is connected to one end of the capacitor C11, a second output end of the power chip T2 and the other end of the capacitor C11 are both grounded, an input end of the voltage stabilizing chip is connected to an input end of the power chip T2, an output end of the voice control circuit and an output end of the voltage stabilizing chip C7 is grounded through the voltage stabilizing chip.

In the above description, the model of the voltage stabilization chip is HX7133, and the model of the power chip T2 is B0505S-1W. The external power supply connected with the series branch formed by connecting the capacitor C1 and the capacitor C2 is 220V commercial power, the commercial power is converted into a direct current power supply, the commercial power is converted into 5V direct current through the power chip T1, and the commercial power is converted into 3.3V direct current through the power chip T2. Also, ground is connected between the capacitor C1 and the capacitor C2, and this ground terminal is also connected to the ground terminal of the external three-phase circuit. The switch K8B can control the on/off of the power circuit to control whether the power circuit operates.

Further, the control circuit of the embodiment includes a control chip, i.e., U6 shown in FIG. 4, preferably, but not exclusively, 89C58-44. Taking the 89C58-44 control chip as an example, the control circuit may include a plurality of pin ports for communication with other circuit units, and for example, the control circuit may further include an indicator light LED1 and an indicator light LED2, the indicator light LED1 is connected to the control chip through a resistor R2, and the indicator light LED2 is connected to the control chip through a resistor R1. For another example, the control chip sets a pin as a buzzer pin, and the buzzer pin is connected with the buzzer BZ2 through the resistor R56 to realize the alarm or voice broadcast function. The control chip also comprises other peripheral circuits, such as a resistor R3, a capacitor C14, a capacitor C15 and an electrolytic capacitor X2. One end of the resistor R3 is connected to the other pin of the control chip, the other end of the resistor R3 is connected with one end of the capacitor C14 and one end of the capacitor C15, one end of the electrolytic capacitor X2 is connected with the capacitor C14, the other end of the electrolytic capacitor X2 is connected with the capacitor C15, and the two ends of the electrolytic capacitor X2 are respectively connected with the XTAL2 pin and the XTAL1 pin of the control chip.

In the embodiment, built-in performance of various selected chips is superior, noninductive design of high-voltage resistance of special glass glaze is realized, low voltage coefficient is realized, voice prompt and broadcasting functions are added, so that the operation is more convenient and humanized, and the measurement of a digital true effective value of 1kHz can be realized by matching with an internal Digital Signal Processor (DSP), and the measurement of a digital true effective value far exceeds that of a 50Hz digital effective value of the conventional high-voltage instrument without any external component.

While only certain components and embodiments of the present application have been illustrated and described, many modifications and changes may occur to those skilled in the art without departing substantially from the scope and spirit of the appended claims, for example: variations in the size, dimensions, structure, shape and proportions of the various elements, mounting arrangements, use of materials, colors, orientations, etc.

The above embodiments are only preferred embodiments of the present invention, and the protection scope of the embodiments of the present invention cannot be limited thereby, and any insubstantial changes and substitutions made by those skilled in the art on the basis of the embodiments of the present invention are all within the scope of the embodiments of the present invention as claimed.

Claims

1. A digital high-voltage meter with high input impedance is characterized by comprising a power supply circuit, a measuring circuit, a control circuit, an attenuation circuit and a voice circuit, wherein the power supply circuit supplies power to the control circuit, the measuring circuit and the voice circuit respectively;

2. The digital high-voltage meter according to claim 1, wherein the attenuation circuit includes a plurality of first capacitors, a resistor R1, and a resistor R2, the plurality of first capacitors are sequentially connected to form a capacitor series branch, one end of the capacitor series branch is connected to one end of the resistor R2, the other end of the capacitor series branch is connected between the resistor R1 and the measurement circuit, and one end of the resistor R1 and the other end of the resistor R2 are connected to an externally input high-voltage electrical signal.

3. The digital high-voltage meter according to claim 2, wherein the first capacitor includes a capacitor C01, a capacitor C02, a capacitor C03, a capacitor C04, a capacitor C05, a capacitor C06, a capacitor C07, a capacitor C08, a capacitor C09, a capacitor C010, a capacitor C011 and a capacitor C012, the capacitors C01, C02, C03, C04, C05, C06, C07, C08, C09, C010, C011 and C012 are connected in sequence to form the capacitor series branch, one end of the capacitor C01 far away from the capacitor C02 is connected to the resistor R2, and one end of the capacitor C012 far away from the capacitor C011 is connected between the resistor R1 and a measurement circuit.

4. The digital voltmeter according to claim 2, wherein the measuring circuit comprises a measuring monolithic chip, a measuring interface circuit, the measuring interface circuit comprises an interface and a voltage dividing circuit, the voltage dividing circuit comprises a transistor Q3, a transistor Q4, a resistor R27, a resistor R18, a resistor R58, a switch K2A and a switch K2B, one end of the interface is connected to the other end of the R1, a base of the transistor Q3 is connected to a base of the transistor Q4, a collector of the transistor Q3 is connected to a collector of the transistor Q4, an emitter of the transistor Q3 is connected to the measuring monolithic chip through a resistor R18, an emitter of the transistor Q4 is grounded, an emitter of the transistor Q4 is further connected to one end of the switch K2A, the other end of the switch K2A is connected to the interface, one end of the resistor R27 is connected to one end of the switch K2B, the other end of the switch K2B is connected to a sliding end of a sliding resistor RV6 through a resistor R58, a fixed end of the resistor RV6 is connected to the interface, the other end of the resistor R27 is connected to one end of the measuring monolithic chip, and the other end of the resistor R58 is connected to the measuring monolithic chip, and the measuring interface circuit controls the measuring chip is connected to the measuring monolithic chip.

5. The digital high pressure gauge according to claim 4, wherein the measuring one-chip is model DTM0660.

6. The digital high-voltage meter according to claim 4, wherein the measuring circuit further comprises a buzzer circuit, the buzzer circuit comprises a buzzer BZ1 and a buffer, an input end of the buffer is connected with the measuring single chip, and the buffer is further connected with the buzzer BZ1.

7. The digital high-voltage meter according to claim 4, wherein the voice circuit comprises a voice interface, a first audio amplifier chip, and a second audio amplifier chip, the voice interface is connected to the control circuit, the first audio amplifier chip and the second audio amplifier chip are both connected to the voice interface, the first audio amplifier chip is LM386+, and the second audio amplifier chip is LM386.

8. The digital high-voltage meter according to claim 7, wherein the power circuit comprises a capacitor C1, a capacitor C2, a capacitor C3, a capacitor C6, a capacitor C7, a capacitor C11, a power chip T1, a power chip T2, a switch K8B, and a voltage stabilizing chip, the capacitor C1 is connected with the capacitor C2 to form a series branch, the series branch is connected with an external power source, one end of the capacitor C3 and a first input end of the power chip T1 are both connected with one end of the series branch, the other end of the capacitor C3 and a second input end of the power chip T2 are both connected with the other end of the series branch, an output end of the power chip T1 is connected with an input end of the power chip T1 through the switch K8B, a ground end of the power chip T2 is connected with a ground end of the capacitor C6, a first output end of the power chip T2 is connected with one end of the capacitor C11, a second output end of the power chip T2 and the other end of the capacitor C11 are both grounded, an input end of the voltage stabilizing chip T2 is connected with an input end of the voltage stabilizing chip T2, an output end of the voltage stabilizing chip is connected with the voice measuring circuit, and the voice chip C7.

9. The digital high voltage meter according to claim 8, wherein the model of the voltage regulator chip is HX7133, and the model of the power supply chip T2 is B0505S-1W.

10. The digital high pressure gauge according to claim 8, wherein the control circuit comprises a control chip, the control chip having a model number of 89C58-44.