Signal generation circuit

Abstract

The utility model relates to the technical field of power electronics, and discloses a signal generating circuit which comprises a square wave generating circuit, a triangular wave generating circuit and a trapezoidal wave generating circuit, an external power supply voltage is input into the power supply end of the square wave generating circuit, and a driving signal is input into the input end of the square wave generating circuit. The output end of the square wave generation circuit is connected with the input end of the triangular wave generation circuit; the output end of the triangular wave generation circuit is connected with the input end of the trapezoidal wave generation circuit, a first power supply end of the triangular wave generation circuit inputs first power supply voltage, and a second power supply end of the triangular wave generation circuit inputs external power supply voltage; the power supply end of the trapezoidal wave generation circuit inputs second power supply voltage; the external supply voltage is greater than the second supply voltage. The signal generating circuit is high in reliability, high in integration level and suitable for multi-path output scenes.

Description

Technical Field

[0001] This utility model relates to the field of power electronics technology, specifically to a signal generation circuit. Background Technology

[0002] With the rapid development of electronic devices, loads driven by various circuit signals are constantly being introduced, demanding increasingly higher reliability and smaller size. In some applications, in addition to loads driven by traditional pulse-width modulation (PWM) technology, trapezoidal wave driven loads have also emerged. For example, some glass-like loads require trapezoidal wave drive, the control principle of which is to control the glass's color and light transmittance by controlling the voltage across the glass. Existing trapezoidal wave generation circuits are mostly built using traditional discrete transistors and resistors / capacitors, which have many potential failure points, poor reliability, and occupy a large area on the printed circuit board (PCB). Especially with multiple outputs, this significantly impacts PCB size, and consequently, product size. Utility Model Content

[0003] In view of this, the present invention provides a signal generation circuit to solve the problem of poor reliability of existing trapezoidal wave generation circuits.

[0004] This invention provides a signal generation circuit, comprising: a square wave generation circuit, a triangular wave generation circuit, and a trapezoidal wave generation circuit. The square wave generation circuit receives an external power supply voltage at its power supply terminal and a driving signal at its input terminal. Its output terminal is connected to the input terminal of the triangular wave generation circuit. The square wave generation circuit is used to chop the external power supply voltage based on the driving signal and output a square wave signal. The triangular wave generation circuit's output terminal is connected to the input terminal of the trapezoidal wave generation circuit. The first power supply terminal of the triangular wave generation circuit receives a first power supply voltage, and its second power supply terminal receives an external power supply voltage. The triangular wave generation circuit is used to output a triangular wave signal based on the square wave signal. The trapezoidal wave generation circuit receives a second power supply voltage at its power supply terminal and is used to clip the triangular wave signal based on the second power supply voltage and output a trapezoidal wave signal. The external power supply voltage is greater than the second power supply voltage.

[0005] The signal generation circuit provided by this utility model generates a square wave by chopping DC current, generates a triangular wave based on the square wave, and then clips the triangular wave to generate a trapezoidal wave. The square wave generation circuit, triangular wave generation circuit and trapezoidal wave generation circuit involved have high integration and high reliability, and occupy less circuit board area than traditional discrete circuits. They are especially suitable for multi-output scenarios and can effectively reduce product size.

[0006] In one optional embodiment, the triangular wave generation circuit includes: a first voltage divider unit, a second voltage divider unit, a comparator unit, and a charging unit. The first terminal of the first voltage divider unit is connected to the output terminal of the square wave generation circuit, the second terminal of the first voltage divider unit is connected to the first input terminal of the comparator unit, and the third terminal of the first voltage divider unit is connected to the output terminal of the comparator unit and the first terminal of the second voltage divider unit. The second terminal of the second voltage divider unit receives an external power supply voltage, and the third terminal of the second voltage divider unit is connected to the second input terminal of the comparator unit, the first terminal of the charging unit, and the input terminal of the trapezoidal wave generation circuit. The second terminal of the charging unit is grounded.

[0007] In one optional embodiment, the first voltage divider unit includes a first resistor, a second resistor, and a third resistor, wherein the first end of the first resistor is connected to the output terminal of the square wave generating circuit, the second end of the first resistor is connected to the first end of the second resistor, the first end of the third resistor, and the first input terminal of the comparator unit; the second end of the second resistor is grounded; and the second end of the third resistor is connected to the output terminal of the comparator unit.

[0008] In one optional embodiment, the second voltage divider unit includes a fourth resistor and a fifth resistor, wherein the first end of the fourth resistor is input to an external power supply voltage, the second end of the fourth resistor is connected to the first end of the fifth resistor and the output terminal of the comparator unit, and the second end of the fifth resistor is connected to the second input terminal of the comparator unit.

[0009] In one alternative implementation, the comparison unit includes a voltage comparator.

[0010] In one alternative implementation, the charging unit includes an energy storage capacitor.

[0011] In one alternative implementation, the trapezoidal wave generation circuit includes an operational amplifier.

[0012] In one optional embodiment, the signal generating circuit further includes a control unit, wherein the power supply terminal of the control unit receives a third power supply voltage, the output terminal of the control unit is connected to the input terminal of the square wave generating circuit, and the control unit is used to output a drive signal.

[0013] In one optional embodiment, the signal generating circuit further includes a voltage conversion circuit, wherein an external power supply voltage is input at the input terminal of the voltage conversion circuit, a second power supply voltage is output at the first output terminal of the voltage conversion circuit, and a third power supply voltage is output at the second output terminal of the voltage conversion circuit.

[0014] In one optional embodiment, the signal generation circuit further includes a filtering unit, wherein a first terminal of the filtering unit receives an external power supply voltage and is connected to a first power supply terminal of the triangular wave generation circuit, a second terminal of the filtering unit is grounded, and the filtering unit is used to filter out interference in the external power supply voltage and output a first power supply voltage. Attached Figure Description

[0015] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of a signal generation circuit according to an embodiment of the present invention;

[0017] Figure 2 This is another component diagram of the signal generation circuit according to an embodiment of the present utility model;

[0018] Figure 3 This is a specific circuit diagram of a signal generation circuit according to an embodiment of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0020] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can also refer to the internal connection of two components; and they can refer to a wireless connection or a wired connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0022] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0023] Traditional trapezoidal wave generation circuits built with discrete transistors and resistors and capacitors have many fault points and are easily affected by ambient temperature, resulting in poor circuit reliability. In addition, the circuit occupies a large area of ​​PCB board, which seriously affects the size of PCB and increases manufacturing costs when multiple trapezoidal waves need to be output.

[0024] This embodiment provides a signal generation circuit, such as Figure 1 As shown, it includes: a square wave generating circuit 1, a triangular wave generating circuit 2, and a trapezoidal wave generating circuit 3. The power supply terminal of the square wave generating circuit 1 is input with an external power supply voltage, the input terminal of the square wave generating circuit 1 is input with a drive signal, and the output terminal of the square wave generating circuit 1 is connected to the input terminal of the triangular wave generating circuit 2. The square wave generating circuit 1 is used to chop the external power supply voltage based on the drive signal and output a square wave signal.

[0025] Optionally, Figure 1 In this circuit, the driving signal can be a waveform such as a PWM wave or a pulse wave that can regularly switch its level. The square wave generation circuit 1 has a built-in controllable switch that can alternately switch on and off states to turn the output on or off according to the level switching frequency of the driving signal, thereby chopping the continuous DC external power supply voltage into a regular square wave signal.

[0026] Optionally, the square wave generating circuit may include controllable switches such as transistors and MOS transistors.

[0027] Figure 1 In the process, the output terminal of the triangular wave generating circuit 2 is connected to the input terminal of the trapezoidal wave generating circuit 3. The first power supply terminal of the triangular wave generating circuit 2 is input with a first power supply voltage, and the second power supply terminal of the triangular wave generating circuit 2 is input with an external power supply voltage. The triangular wave generating circuit 2 is used to output a triangular wave signal based on a square wave signal.

[0028] Specifically, Figure 1In this circuit, a square wave signal is used to charge and discharge the energy storage unit within the triangular wave generation circuit 2. The high-level voltage of the square wave signal is the external power supply voltage, and the low-level voltage is zero. When the square wave generation circuit 1 is turned on, it outputs a high level, and the external power supply voltage charges the energy storage unit in the triangular wave generation circuit 2. The voltage across the energy storage unit gradually increases, causing the triangular wave generation circuit 2 to output a waveform with an upward slope. When the square wave generation circuit 1 is turned off, it outputs a low level, and the external power supply voltage stops charging the energy storage unit. The voltage across the energy storage unit gradually decreases as it discharges, causing the triangular wave generation circuit 2 to output a waveform with a downward slope, forming a triangular wave. After multiple cycles, the triangular wave generation circuit 2 outputs a continuous triangular wave.

[0029] Figure 1 In the process, the power supply terminal of the trapezoidal wave generation circuit 3 is input with a second power supply voltage. The trapezoidal wave generation circuit 3 is used to clip the triangular wave signal based on the second power supply voltage and output a trapezoidal wave signal. The external power supply voltage is greater than the second power supply voltage.

[0030] Specifically, Figure 1 In the process, since the second power supply voltage is less than the external power supply voltage, the saturation voltage of the trapezoidal wave generating circuit 3 is less than the peak value of the triangular wave output by the triangular wave generating circuit 2. After the triangular wave passes through the trapezoidal wave generating circuit 3, the peak is clipped, thus converting it into a trapezoidal wave output.

[0031] Optionally, the trapezoidal wave generation circuit 3 may include an operational amplifier.

[0032] The signal generation circuit provided in this embodiment generates a square wave by chopping DC current, generates a triangular wave based on the square wave, and then clips the triangular wave to generate a trapezoidal wave. The square wave generation circuit, triangular wave generation circuit, and trapezoidal wave generation circuit involved have high integration and high reliability, and occupy less circuit board area compared with traditional discrete circuits. They are especially suitable for multi-output scenarios and can effectively reduce product size.

[0033] In some alternative implementations, such as Figure 2 As shown, the triangular wave generating circuit 2 includes: a first voltage divider unit 21, a second voltage divider unit 22, a comparator unit 23, and a charging unit 24. The first end of the first voltage divider unit 21 is connected to the output end of the square wave generating circuit 1, the second end of the first voltage divider unit 21 is connected to the first input end of the comparator unit 23, and the third end of the first voltage divider unit 21 is connected to the output end of the comparator unit 23 and the first end of the second voltage divider unit 22. The second end of the second voltage divider unit 22 receives an external power supply voltage, and the third end of the second voltage divider unit 22 is connected to the second input end of the comparator unit 23, the first end of the charging unit 24, and the input end of the trapezoidal wave generating circuit 3. The second end of the charging unit 24 is grounded.

[0034] Specifically, Figure 2 The process for generating waveforms includes the following:

[0035] (1) When the square wave generating circuit 1 is turned on, it outputs a high level. The high level voltage is divided by the first voltage divider unit 21 and input to the first input terminal of the comparison unit 23. At this time, there is no charge in the charging unit 24, that is, the voltage of the second input terminal of the comparison unit 23 is less than the voltage of the first input terminal of the comparison unit 23. The comparison unit 23 outputs a high level so that the external power supply voltage charges the charging unit 24 through the second voltage divider unit 22. The voltage of the first terminal of the charging unit 24 gradually increases, so that the input terminal of the trapezoidal wave generating circuit 3 receives a waveform with an upward slope.

[0036] (2) When the square wave generating circuit 1 is turned off, it outputs a low level. The voltage of the first input terminal of the comparison unit 23 is 0V, which is less than the voltage of the second input terminal of the comparison unit 23. The low level output of the comparison unit 23 causes the external power supply voltage to stop charging the energy storage unit. Then the charging unit 24 starts to discharge, causing the voltage of the first terminal of the charging unit 24 to gradually decrease. The input terminal of the trapezoidal wave generating circuit 3 then receives a waveform with a falling slope.

[0037] Optionally, both the first voltage divider unit 21 and the second voltage divider unit 22 are composed of multiple resistors connected in series, in parallel, or in a series-parallel connection.

[0038] Specifically, Figure 3 In the first voltage divider unit 21, there are: a first resistor R1, a second resistor R2 and a third resistor R3. The first end of the first resistor R1 is connected to the output end of the square wave generating circuit 1. The second end of the first resistor R1 is connected to the first end of the second resistor R2, the first end of the third resistor R3 and the first input end of the comparison unit 23. The second end of the second resistor R2 is grounded. The second end of the third resistor R3 is connected to the output end of the comparison unit 23.

[0039] Specifically, Figure 3 In the second voltage divider unit 22, there are: a fourth resistor R4 and a fifth resistor R5. The first end of the fourth resistor R4 is connected to the external power supply voltage VDD24V. The second end of the fourth resistor R4 is connected to the first end of the fifth resistor R5 and the output end of the comparator unit 23. The second end of the fifth resistor R5 is connected to the second input end of the comparator unit 23.

[0040] Specifically, Figure 3In the circuit, the comparison unit 23 includes a voltage comparator U1A, whose power supply terminal is connected to a first power supply voltage VDD1; the charging unit 24 includes an energy storage capacitor C1; the trapezoidal wave generation circuit 3 includes an operational amplifier U2B, whose power supply terminal is connected to a second power supply voltage VDD2, meaning the saturation voltage of the operational amplifier U2B is the second power supply voltage VDD2, which is less than the peak voltage of the triangular wave output by the triangular wave generation circuit 2, thus clipping the triangular wave to output a trapezoidal wave. R0 represents the load driven by the trapezoidal wave, such as some glass-like loads.

[0041] In some alternative implementations, such as Figure 3 As shown, the signal generation circuit also includes a control unit 4, wherein the power supply terminal of the control unit 4 is input with a third power supply voltage VCC1, the output terminal of the control unit 4 is connected to the input terminal of the square wave generation circuit 1, and the control unit 4 is used to output a drive signal.

[0042] Specifically, the control unit 4 is a processor control chip such as MCU or DSP, which integrates mature control software from existing technologies and can output expected high and low level drive signals according to the operator's settings.

[0043] In some alternative implementations, such as Figure 3 As shown, the signal generation circuit also includes a voltage conversion circuit 5, wherein the input terminal of the voltage conversion circuit 5 receives an external power supply voltage VDD24V, the first output terminal of the voltage conversion circuit 5 outputs a second power supply voltage VDD2, and the second output terminal of the voltage conversion circuit 5 outputs a third power supply voltage VCC1.

[0044] Optionally, the voltage conversion circuit includes two DC-DC converters, DCDC1 and DCDC2, which are used to convert the external power supply voltage VDD24V into a second supply voltage VDD2 and a third supply voltage VCC1 of different voltage levels, respectively. The second supply voltage VDD2 supplies power to the comparator unit, and the third supply voltage VCC1 supplies power to the control unit.

[0045] In some alternative implementations, such as Figure 3 As shown, the signal generation circuit also includes a filter unit 6, wherein the first end of the filter unit 6 is connected to the first power supply terminal of the triangular wave generation circuit 2 and is connected to the external power supply voltage VDD24V, and the second end of the filter unit 6 is grounded.

[0046] Optionally, the filter unit can be composed of capacitors, resistors and inductors, used to filter out the interference of VDD24V in the external power supply voltage and output the first power supply voltage VDD1.

[0047] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A signal generation circuit, characterized in that, include: Square wave generation circuit, triangle wave generation circuit and trapezoidal wave generation circuit, among which, The power supply terminal of the square wave generating circuit receives an external power supply voltage, the input terminal of the square wave generating circuit receives a driving signal, and the output terminal of the square wave generating circuit is connected to the input terminal of the triangular wave generating circuit. The square wave generating circuit is used to chop the external power supply voltage based on the driving signal and output a square wave signal. The output terminal of the triangular wave generating circuit is connected to the input terminal of the trapezoidal wave generating circuit. The first power supply terminal of the triangular wave generating circuit receives a first power supply voltage, and the second power supply terminal of the triangular wave generating circuit receives an external power supply voltage. The triangular wave generating circuit is used to output a triangular wave signal based on the square wave signal. The trapezoidal wave generation circuit receives a second power supply voltage at its power supply terminal, and the trapezoidal wave generation circuit is used to clip the triangular wave signal based on the second power supply voltage and output a trapezoidal wave signal. The external power supply voltage is greater than the second power supply voltage.

2. The signal generating circuit according to claim 1, characterized in that, The triangular wave generation circuit includes: a first voltage divider unit, a second voltage divider unit, a comparator unit, and a charging unit, wherein... The first end of the first voltage divider unit is connected to the output end of the square wave generating circuit, the second end of the first voltage divider unit is connected to the first input end of the comparator unit, and the third end of the first voltage divider unit is connected to the output end of the comparator unit and the first end of the second voltage divider unit. The second terminal of the second voltage divider unit receives an external power supply voltage, and the third terminal of the second voltage divider unit is connected to the second input terminal of the comparator unit, the first terminal of the charging unit, and the input terminal of the trapezoidal wave generation circuit. The second terminal of the charging unit is grounded.

3. The signal generating circuit according to claim 2, characterized in that, The first voltage divider unit includes: a first resistor, a second resistor, and a third resistor, wherein, The first end of the first resistor is connected to the output end of the square wave generating circuit, and the second end of the first resistor is connected to the first end of the second resistor, the first end of the third resistor, and the first input end of the comparison unit. The second terminal of the second resistor is grounded; The second end of the third resistor is connected to the output end of the comparison unit.

4. The signal generating circuit according to claim 2, characterized in that, The second voltage divider unit includes: a fourth resistor and a fifth resistor, wherein, The first terminal of the fourth resistor is input to an external power supply voltage, and the second terminal of the fourth resistor is connected to the first terminal of the fifth resistor and the output terminal of the comparison unit. The second end of the fifth resistor is connected to the second input end of the comparison unit.

5. The signal generating circuit according to claim 2, characterized in that, The comparison unit includes a voltage comparator.

6. The signal generating circuit according to claim 2, characterized in that, The charging unit includes an energy storage capacitor.

7. The signal generating circuit according to claim 1, characterized in that, The trapezoidal wave generation circuit includes an operational amplifier.

8. The signal generating circuit according to claim 1, characterized in that, Also includes: Control unit, wherein, The power supply terminal of the control unit receives a third power supply voltage, the output terminal of the control unit is connected to the input terminal of the square wave generating circuit, and the control unit is used to output the drive signal.

9. The signal generating circuit according to claim 1, characterized in that, Also includes: Voltage conversion circuit, in which, The voltage conversion circuit receives an external power supply voltage at its input terminal, outputs a second power supply voltage at its first output terminal, and outputs a third power supply voltage at its second output terminal.

10. The signal generating circuit according to claim 1, characterized in that, Also includes: Filtering unit, wherein, The first terminal of the filter unit receives an external power supply voltage and is connected to the first power supply terminal of the triangular wave generating circuit. The second terminal of the filter unit is grounded. The filter unit is used to filter out interference in the external power supply voltage and output the first power supply voltage.

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