A circuit structure and electronic device for sawtooth waveform control

Abstract

The present invention discloses a circuit structure and an electronic device. The circuit structure includes: a charging circuit, which is used to transmit the power supply current of a power supply circuit to a sawtooth wave generating circuit under a first pulse signal; a discharging circuit, which is used to adjust the voltage of the sawtooth wave generating circuit under a second pulse signal, and disconnect the power supply circuit from the sawtooth wave generating circuit during the second pulse signal; a comparison circuit, which is used to compare the voltage of the sawtooth wave generating circuit with a reference voltage and output a first level to an operational amplifier circuit; and an operational amplifier circuit, which is used to adjust the power supply current of the power supply circuit based on the first level.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuits, and in particular to a circuit structure and electronic equipment for sawtooth waveform control. Background Art

[0002] A sawtooth wave circuit refers to a circuit that can periodically generate a sawtooth signal. It controls a current to charge a capacitor through a control signal, and then controls the discharge of the capacitor by comparing the capacitor terminal with a reference voltage through a comparator, ultimately obtaining a sawtooth wave.

[0003] In conventional sawtooth waveform circuits, the charging current and capacitor capacitance determine the sawtooth waveform. However, these values ​​can vary depending on operating conditions such as manufacturing process, operating voltage, and operating temperature. Consequently, variations in the charging current and capacitor capacitance in conventional sawtooth waveform circuits can lead to larger deviations in the sawtooth waveform. Summary of the Invention

[0004] In view of this, the present invention proposes a circuit structure and electronic device for sawtooth waveform control, the main purpose of which is to reduce the deviation of the sawtooth waveform.

[0005] In order to achieve the above object, the present invention mainly provides the following technical solutions:

[0006] In a first aspect, the present invention provides a circuit structure for sawtooth waveform control, the circuit structure comprising: a charging circuit, a discharging circuit, a power supply circuit, a sawtooth wave generating circuit, a comparison circuit, and an operational amplifier circuit;

[0007] The charging circuit is configured to transmit the power supply current of the power supply circuit to the sawtooth wave generating circuit under a first pulse signal;

[0008] The discharge circuit is used to adjust the voltage of the sawtooth wave generating circuit under the second pulse signal, wherein the power supply circuit is disconnected from the sawtooth wave generating circuit when the second pulse signal is applied;

[0009] The comparison circuit is configured to compare the voltage of the sawtooth wave generating circuit with a reference voltage and output a first level to the operational amplifier circuit;

[0010] The operational amplifier circuit is configured to adjust a power supply current of the power supply circuit based on the first level.

[0011] In a second aspect, the present invention provides an electronic device, which includes: the circuit structure described in the first aspect.

[0012] By means of the above-mentioned technical solution, the circuit structure and electronic device provided by the present invention have the following characteristics: the charging circuit transmits the supply current of the power supply circuit to the sawtooth wave generating circuit under a first pulse signal. The comparison circuit compares the voltage of the sawtooth wave generating circuit with a reference voltage and outputs a first voltage level to the operational amplifier circuit. The operational amplifier circuit adjusts the supply current of the power supply circuit based on the first voltage level. After the first pulse signal is transmitted, the discharge circuit adjusts the voltage of the sawtooth wave generating circuit under a second pulse signal. The comparison circuit transmits the first voltage level to the operational amplifier circuit based on the voltage in the sawtooth wave generating circuit adjusted by the discharge circuit. The operational amplifier circuit adjusts the supply current of the power supply circuit based on the first voltage level. It can be seen that the solution provided by the embodiment of the present invention adjusts the supply current of the power supply circuit by feeding back a voltage level related to the sawtooth wave generating circuit voltage to the operational amplifier circuit through the comparison circuit, so that the supply current is maintained in a stable state, thereby enabling the sawtooth wave generating circuit to generate a sawtooth wave with a stable waveform under a stable supply current. Therefore, the solution provided by the embodiment of the present invention can achieve precise control of the sawtooth wave waveform and reduce sawtooth wave waveform deviation.

[0013] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are specifically listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0015] Figure 1 A schematic diagram showing a circuit structure provided by an embodiment of the present invention is shown;

[0016] Figure 2 A schematic diagram showing a circuit structure provided by another embodiment of the present invention;

[0017] Figure 3 A schematic diagram of a charging circuit provided by an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0018] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0019] like Figure 1 As shown, the embodiment of the present invention provides a circuit structure for sawtooth waveform control, which mainly includes: a charging circuit 11, a power supply circuit 12, a sawtooth wave generating circuit 13, a comparison circuit 14, an operational amplifier circuit 15, and a discharge circuit 16, wherein:

[0020] The charging circuit 11 is used to transmit the power supply current of the power supply circuit 12 to the sawtooth wave generating circuit 13 under the first pulse signal.

[0021] The discharge circuit 16 is used to adjust the voltage of the sawtooth wave generating circuit 13 under the second pulse signal, wherein the power supply circuit 12 is disconnected from the sawtooth wave generating circuit 13 under the second pulse signal.

[0022] The comparison circuit 14 is configured to compare the voltage of the sawtooth wave generating circuit 13 with a reference voltage and output a first level to the operational amplifier circuit 15 .

[0023] The operational amplifier circuit 15 is configured to adjust the power supply current of the power supply circuit 12 based on the first level.

[0024] Each circuit in the circuit structure mainly operates through multiple pulse cycles to maintain the power supply current transmitted by the power supply circuit 12 to the sawtooth wave generating circuit 13 at a stable value, so that the sawtooth wave generating circuit 13 generates a sawtooth wave under a stable current, reducing the deviation of the sawtooth wave waveform.

[0025] The working process of each circuit in the circuit structure is the same in each pulse cycle. Therefore, the working process of each circuit in the circuit structure is described below using one pulse cycle as an example:

[0026] The working process of each circuit under the first pulse signal is:

[0027] Under the first pulse signal of the current pulse cycle, the charging circuit 11 transmits the supply current from the power supply circuit 12 to the sawtooth wave generating circuit 13. The sawtooth wave generating circuit 13 generates a linear rising edge waveform of the sawtooth wave under the supply current. The comparison circuit 14 compares the voltage of the sawtooth wave generating circuit 13 with a reference voltage and outputs a first voltage level to the operational amplifier circuit 15. At this point, the voltage of the sawtooth wave generating circuit 13 is generated by the supply current being transmitted to the sawtooth wave generating circuit 13. The operational amplifier circuit 15 then adjusts the supply current of the power supply circuit 12 based on the first voltage level transmitted by the comparison circuit 14.

[0028] The working process of each circuit under the second pulse signal is:

[0029] When the first pulse signal of the current pulse cycle ends and the second pulse signal of the current pulse cycle begins, the charging circuit 11 disconnects the power supply circuit 12 from the sawtooth wave generating circuit 13 in response to the second pulse signal of the current pulse cycle. Simultaneously, the discharge circuit 16 adjusts the voltage of the sawtooth wave generating circuit in response to the second pulse signal. Under the adjustment of the discharge circuit 16, the sawtooth wave generating circuit 13 generates a linear falling end waveform of the sawtooth wave. The comparison circuit 14 compares the voltage of the sawtooth wave generating circuit 13 with a reference voltage and outputs a first voltage level to the operational amplifier circuit 15. At this point, the voltage of the sawtooth wave generating circuit 13 is the voltage adjusted by the discharge circuit 16. The operational amplifier circuit 15 then adjusts the supply current of the power supply circuit 12 based on the first voltage level transmitted by the comparison circuit 14.

[0030] Through the working conditions of each circuit in the circuit structure under the above-mentioned first pulse signal and second pulse signal, it can be seen that when the current pulse cycle is the first pulse cycle, the power supply current transmitted by the charging circuit 11 to the sawtooth wave generating circuit 13 under the first pulse signal is the current in the initial state of the power supply circuit 12. When the current pulse cycle is not the first pulse cycle, the power supply current transmitted by the charging circuit 11 to the sawtooth wave generating circuit 13 under the first pulse signal is the power supply current adjusted by the operational amplifier circuit 15 under the second pulse signal of the previous pulse cycle adjacent to the current pulse cycle.

[0031] The following is a detailed description of each circuit in the circuit structure and the relationship between the circuits:

[0032] Charging circuit 11:

[0033] To enable sawtooth wave generating circuit 13 to generate a sawtooth wave, the timing and duration of the supply current transmitted by charging circuit 11 to sawtooth wave generating circuit 13 are controlled by a pulse signal. In other words, charging circuit 11 is turned on and off by a periodic pulse signal. A pulse cycle includes a first pulse signal and a second pulse signal. In response to the first pulse signal, charging circuit 11 transmits the supply current from power supply circuit 12 to sawtooth wave generating circuit 13. In response to the second pulse signal, charging circuit 11 disconnects power supply circuit 12 from sawtooth wave generating circuit 13.

[0034] In practical applications, the charging circuit 11 needs to be connected to a narrow pulse generator to receive the pulse signal sent by the narrow pulse generator and perform actions corresponding to the pulse signal it receives. In one cycle, the narrow pulse generator sends two pulse signals, one of which is a rising edge pulse signal when it jumps from a low level to a high level, and conversely, the other pulse signal is a falling edge pulse signal when it jumps from a high level to a low level. For example, the first pulse signal in this embodiment is a falling edge pulse signal, that is, a low level signal. The second pulse signal in this embodiment is a rising edge pulse signal, that is, a high level signal.

[0035] The specific structure of the charging circuit 11 can be set based on specific business requirements and is not specifically limited in this embodiment. For example, the specific results of the charging circuit 11 include the following two:

[0036] The first one, such as Figure 2 As shown, the charging circuit 11 includes a second inverter 111, a first switch element 112, and a second switch element 113. The connection relationship between the second inverter 111, the first switch element 112, and the second switch element 113 is as follows:

[0037] The first switching element 112 has a first terminal a1 connected to a fifth node A5, a second terminal a2 connected to the sawtooth wave generating circuit 13, and a third terminal a3 connected to a sixth node A6. The second switching element 113 has a first terminal b1 connected to a fifth node A5, a second terminal b2 connected to a target potential terminal, i.e., ground GND, and a third terminal b3 connected to an output terminal c2 of the second inverter 111. The input terminal c1 of the second inverter 111 is connected to a sixth node A6. The fifth node A5 is connected to the power supply circuit 11, and the sixth node A6 is used to receive the first pulse signal or the second pulse signal.

[0038] The first switching element 112 is turned on by the first pulse signal and transmits the power supply current of the power supply circuit 11 received by the fifth node A5 to the sawtooth wave generating circuit 13. Simultaneously, the second inverter 111 inverts the first pulse signal by the first pulse signal and transmits the inverted first pulse signal to the second switching element 113. The second switching element 113 is turned off by the inverted first pulse signal.

[0039] The first pulse signal in one cycle is a low level signal, which is used to trigger the first switch element 112 to turn on and the second switch element 113 to turn off. The first pulse signal is provided by a narrow pulse generator, such as Figure 2 The B in it is the narrow pulse signal provided by the narrow pulse generator. The falling edge pulse signal when it jumps from high level to low level is the first pulse signal.

[0040] When the first pulse signal is transmitted to the first switching element 112, triggering the first switching element 112 to turn on, the second inverter 111 inverts the first pulse signal, and the second switching element 113 is turned off by the inverted first pulse signal. This prevents the supply current from flowing to the target potential end during the process of transmitting the supply current to the sawtooth wave generating circuit 13 when the first switching element 112 is turned on. The target potential end here can be set based on specific business needs. For example, the target potential end is the ground line.

[0041] After the first pulse signal is input and sent within a cycle, the second pulse signal within the cycle begins to be input. The second pulse signal is a high-level signal. The first switch element 112 is closed by the second pulse signal. At the same time, the second inverter 111 inverts the second pulse signal under the second pulse signal and transmits the inverted second pulse signal to the second switch element 113. The second switch element 113 is turned on by the inverted second pulse signal.

[0042] When the second pulse signal is transmitted to the first switch element 112, triggering the first switch element 112 to close, the second inverter 111 inverts the second pulse signal, and the second switch element 113 is turned on under the inverted first pulse signal. Therefore, when the first switch element 112 is closed, the current provided by the power supply circuit 12 can be transmitted to the target potential end "ground line", thereby achieving the purpose of freewheeling.

[0043] The first switch element 112 and the second switch element 113 are both P-type MOS transistors or P-type transistors.

[0044] The second type, such as Figure 3 As shown, Figure 3 Only the components included in the charging circuit 11, as well as the power supply circuit 12 and the sawtooth wave generating circuit 13 connected to the charging circuit 11 are shown. The charging circuit 11 includes a controller 114, a first target switch 115, and a second target switch 116. The connection relationship between the controller 114, the first target switch 115, and the second target switch 116 is as follows:

[0045] A first end of the first target switch 115 is connected to the power supply circuit 12, and a second end is connected to the sawtooth wave generating circuit 13. A first end of the second target switch 116 is connected to the power supply circuit 12, and a second end is connected to the target potential terminal, i.e., ground line GND. A first end of the controller 114 is connected to the target node B. The target node B is configured to receive the first pulse signal or the second pulse signal.

[0046] The controller 114 controls the first target switch 115 to turn on under the first pulse signal, transmitting the power supply current of the first power circuit 11 to the sawtooth wave generating circuit 13. At the same time, the controller 114 controls the second target switch 116 to turn off under the first pulse signal, thereby preventing the power supply current from flowing to the target potential end during the process of transmitting the power supply current to the sawtooth wave generating circuit 13 when the first target switch 115 is turned on. The target potential end here can be set based on specific business needs. For example, the target potential end is the ground line.

[0047] After the first pulse signal is input and sent within a cycle, the second pulse signal of the cycle begins to be input. This second pulse signal is a high-level signal. In response to the second pulse signal, the controller 114 controls the first target switch 115 to be closed. Simultaneously, in response to the second pulse signal, the controller 114 controls the second target switch 116 to be open. This allows the current provided by the power supply circuit 12 to be transferred to the target potential terminal "ground" when the first target switch 115 is closed, thereby achieving the purpose of freewheeling.

[0048] Power supply circuit 12:

[0049] The power supply circuit 12 is used to provide power supply current to the sawtooth wave generating circuit 13. The power supply circuit 12 is connected to the charging circuit 11, and its power supply current needs to be transmitted to the sawtooth wave generating circuit 13 under the transmission of the charging circuit 11. Figure 2 As shown, the power supply circuit 12 includes a first capacitor 121 and a target element 122 . The connection relationship between the first capacitor 121 and the target element 122 will be described below.

[0050] The first end of the first capacitor 121 is connected to a preset power supply, and the second end is connected to a first node A1. The first end d1 of the target element 122 is connected to a preset power supply V, the second end d2 is connected to the charging circuit 11, and the third end d3 is connected to the first node A1. The first node A1 is connected to the operational amplifier circuit 15. The first current provided by the target element to the charging circuit 11 can vary with the adjustment of the operational amplifier circuit 15, which can be a P-type MOS transistor or a P-type transistor.

[0051] In the continuous multiple pulse cycles, the power supply current of the power supply circuit 12 is always in the dynamic adjustment process and will eventually be maintained in a steady state range. The adjustment process includes the current increase process and the current decrease process. The increase process occurs in Figure 2 Point F in the equation is lower than vref, and the reduction process occurs when point F is higher than vref.

[0052] The first capacitor 121 is used to stabilize Figure 2 The voltage at point A1 is the main pole, so first capacitor 121 serves as a compensation capacitor. Operational amplifier circuit 15 adjusts the voltage at first node A1 throughout the entire cycle. After the voltage at first node A1 is adjusted by operational amplifier circuit 15, the supply current ireg transmitted by target element 121 changes, ultimately maintaining the average value of supply current ireg unchanged.

[0053] When the received first level is a low level, the operational amplifier circuit 15 decreases the voltage of the first node A1, wherein the supply current transmitted by the target component 122 to the charging circuit 11 increases as the voltage of the first node A1 decreases. Similarly, when the received first level is a high level, the operational amplifier circuit 15 increases the voltage of the first node A1, wherein the supply current transmitted by the target component 122 to the charging circuit 11 decreases as the voltage of the first node A1 increases.

[0054] Sawtooth wave generating circuit 13:

[0055] The sawtooth wave generating circuit 13 is used to generate a sawtooth wave. The obvious characteristic of a sawtooth wave is that the voltage or current first increases linearly with time, then decreases rapidly, then increases linearly again, then decreases rapidly again, and so on. The obvious characteristic of the sawtooth wave is achieved by controlling the charge and discharge of the capacitor.

[0056] The sawtooth wave generating circuit 13 includes a third target circuit 131 and a fourth capacitor 132. The third target circuit 131 and the fourth capacitor 132 are connected as follows: a first end of the third target circuit 131 is connected to the charging circuit 11 and the discharging circuit 16, respectively, and a second end is connected to a ninth node A9. A first end of the fourth capacitor 132 is connected to the ninth node A9, and a second end is connected to the target potential terminal, i.e., the ground line GND. The ninth node A9 is connected to the comparison circuit 14.

[0057] When the third target circuit 131 receives the supply current from the charging circuit 11, it transmits the supply current to the fourth capacitor 132, charging the fourth capacitor 132. The charging process of the fourth capacitor 132 causes the voltage to slowly rise. When the charging circuit 11 stops transmitting the supply current and the discharge circuit 16 is turned on, the fourth capacitor 132 discharges to the target potential end, i.e., the ground line GND, causing the voltage to drop rapidly, thus forming a sawtooth waveform.

[0058] Comparison circuit 14:

[0059] The comparison circuit 14 is used to compare the voltage of the sawtooth wave generating circuit 13 with the reference voltage and output a first level to the operational amplifier circuit 15 , so that the operational amplifier circuit 14 can adjust the power supply current of the power supply circuit 12 based on the first level.

[0060] Comparison circuit 14 includes a comparator 141. Comparator 141 is connected as follows: its positive input is connected to sawtooth wave generator circuit 13, and its negative input is connected to a circuit providing a reference voltage vref. Comparator 141 compares the voltage of sawtooth wave generator circuit 13 with the reference voltage and outputs a first level to op amp circuit 15.

[0061] Op amp circuit 15:

[0062] The operational amplifier circuit 15 is mainly used to adjust the supply current of the power supply circuit 12 according to the first level provided by the comparator circuit 14. The operational amplifier circuit 15 includes an amplifier 151, a first inverter 152, a first target circuit 153, and a second target circuit 154. The connection relationship between the amplifier 151, the first inverter 152, the first target circuit 153, and the second target circuit 154 is described below:

[0063] The first input terminal e1 of the amplifier 151 is connected to the output terminal f2 of the first inverter 152 via the first target circuit 153. The second input terminal e2 is connected to the second node A2 via the second target circuit 154. The output terminal e3 is connected to the power supply circuit 12. The input terminal f1 of the first inverter 152 is connected to the second node A2. The second node A2 is connected to the comparison circuit 14.

[0064] Under the first pulse signal, the comparison circuit 14 transmits a first level to the second node A2. Upon receiving the first level transmitted by the comparison circuit 14 to the second node A2, the first inverter 152 inverts the first level. The first level is transmitted to the amplifier 151 via the first destination circuit 153. Similarly, upon receiving the first level transmitted by the comparison circuit 14 to the second node A2, the second destination circuit 154 transmits the first level to the amplifier 151 via the second destination circuit 154. Amplifier 151 performs an amplification operation based on the first level inverted by the first inverter 152 and the first level transmitted by the second destination circuit, and outputs the result to the power supply circuit 12. The result is used to adjust the current in the power supply circuit.

[0065] In order to disperse the voltage of the amplifier 151 , the first target circuit 153 is provided with a first resistor 1531 and a second capacitor 1532 . The second target circuit 154 is provided with a second resistor 1541 and a third capacitor 1542 .

[0066] The first end of the first resistor 1531 is connected to the output terminal f2 of the first inverter 152, and the second end is connected to the third node A3. The first end of the second capacitor 1532 is connected to the third node A3, and the second end is connected to the target potential terminal, that is, the ground line GND. The third node A3 is connected to the first input terminal e1 of the amplifier 151.

[0067] When the comparison circuit 14 transmits a first level to the second node A2 that exceeds the tolerance of the amplifier 151, the first resistor 1531 will carry a voltage that exceeds the tolerance of the amplifier 151 and transmit the carried voltage to the target potential terminal through the second capacitor 1532. The target potential terminal is the ground line.

[0068] The second target circuit 154 includes a second resistor 1541 and a third capacitor 1542. The first end of the second resistor 1541 is connected to the second node A2, and the second end is connected to the fourth node A4. The first end of the third capacitor 1542 is connected to the fourth node A4, and the second end is connected to the target potential terminal, i.e., the ground line GND. The fourth node A4 is connected to the second input terminal e2 of the amplifier 151.

[0069] In order to reduce the ripple of the operation result output by the amplifier 151 to the power supply circuit 12 , the operational amplifier circuit 151 further includes a first diode 155 and a second diode 156 .

[0070] The first diode 155 and the second diode 156 are disposed between the first target circuit 153 and the second target circuit 154. The cathode of the first diode 155 is connected to the second target circuit 154, and the anode is connected to the first target circuit 153. The cathode of the second diode 156 is connected to the first target circuit 153, and the anode is connected to the second target circuit 154.

[0071] The comparison circuit 14 transmits the first level to the second node A2. Since the comparison circuit 14 has a low-resistance output, the second resistor 1541 is connected to the third capacitor 1542 for low-pass filtering.

[0072] Discharge circuit 16:

[0073] The sawtooth wave generating circuit 13 is used to generate a sawtooth wave. A sawtooth wave's defining characteristic is that the voltage or current first increases linearly over time, then rapidly decreases, then increases linearly again, then rapidly decreases, and so on. These distinct characteristics of a sawtooth wave are achieved by controlling the charge and discharge of a capacitor. The charging circuit 11 is used to charge the capacitor of the sawtooth wave generating circuit 13, while the discharging circuit 16 is used to control the discharge of the capacitor of the sawtooth wave generating circuit 13.

[0074] The discharge circuit 16 includes a third switching element 161;

[0075] The third switch element 161 has a first terminal g1 connected to a seventh node A7, a second terminal g2 connected to a target potential terminal, i.e., ground GND, and a third terminal g3 connected to an eighth node A8. The seventh node A7 is connected to the charging circuit 11 and the sawtooth wave generating circuit 13, respectively. The eighth node A8 is used to receive the first pulse signal or the second pulse signal.

[0076] In order to ensure the generation of the sawtooth wave in the sawtooth wave generating circuit 13 , the control of the discharge circuit 16 and the charging circuit 11 are opposite.

[0077] Under the first pulse signal, when the charging circuit 11 charges the sawtooth wave generating circuit 13, the third switch element 161 is turned off. Under the second pulse signal, when the charging circuit 11 stops charging the sawtooth wave generating circuit 13, the third switch element 161 is turned on, thereby pulling the voltage of the sawtooth wave generating circuit 13 down to the target potential end. The target potential end is the ground line.

[0078] Further, another embodiment of the present invention is described below. Figure 2 The specific working process of the circuit structure shown is explained as follows:

[0079] Figure 2 The working process of the circuit structure shown is:

[0080] The initial state of the circuit structure:

[0081] In the initial state of the circuit structure, that is, when the narrow pulse controller does not initiate a pulse cycle, the voltage in the sawtooth wave generating circuit 13 is zero, that is, Figure 2 The initial level of point F is zero. Due to the presence of the first capacitor 121, the voltage of the first node A1 is the voltage of the preset power supply V. The supply current ireg is zero at this time.

[0082] The first stage of loop establishment is when the pulse controller initiates the pulse cycle to Figure 2 The voltage at point F is higher than the reference voltage vref:

[0083] The working process of the circuit structure is basically the same in each pulse cycle of this stage, so one pulse cycle is used as an example to illustrate:

[0084] D11. For the charging circuit 11, the first switch element 112 is turned on by the first pulse signal of the current pulse cycle, ie, the low-level pulse signal. The second switch element 113 is turned off by the first pulse signal of the current pulse cycle.

[0085] D12. For the discharge circuit 16, the third switch element 161 is turned off under the first pulse signal of the current pulse cycle.

[0086] D13. For the power supply circuit 12, when the first switch element 112 is turned on, its power supply current ireg is transmitted to the sawtooth wave generating circuit 13 through the charging circuit 11, the fourth capacitor 132 starts to charge, and the third target circuit 131 generates a first voltage corresponding to the power supply current ireg, that is, Figure 2 The voltage corresponding to point F.

[0087] D14. For the sawtooth wave generating circuit 13, the fourth capacitor 132 is charged under the supply current, and the third target circuit 131 generates a linear rising end waveform of the sawtooth wave.

[0088] D15 . For the comparison circuit 14 , since the voltage at point F is lower than the reference voltage vref, the first level transmitted by the comparator 141 to the operational amplifier circuit 15 is a low level.

[0089] D16, for the operational amplifier circuit 15, due to the existence of the first inverter 152, when the first level is transmitted to the amplifier 151, Figure 2 When the voltage at point M in the circuit is higher than the voltage at point N, the amplifier 151 reduces the voltage at the first node A1. The supply current ireg increases as the voltage at the first node A1 decreases.

[0090] After the first pulse signal of the current pulse cycle is sent, and the second pulse signal of the current pulse cycle is sent, the working process of each circuit is as follows:

[0091] D21. For the charging circuit 11, the first switch element 112 is turned off under the second pulse signal of the current pulse cycle, ie, the high-level pulse signal. The second switch element 113 is turned on under the second pulse signal of the current pulse cycle.

[0092] D22: For the discharge circuit 16, the third switch element 161 is turned on under the second pulse signal of the current pulse cycle and pulls down the fourth capacitor 132 in the sawtooth wave generating circuit 13 to the target potential end, ie, the ground line GND.

[0093] D23. For the sawtooth wave generating circuit 13, the voltage of the fourth capacitor 132 is pulled down to the target potential end by the opening of the third switch element 161, and the third target circuit 131 generates a rapidly falling end waveform of the sawtooth wave.

[0094] D24. For the comparison circuit 14, since the voltage of the third target circuit 131 is pulled down, the voltage at point F is lower than the reference voltage vref. At this time, the first level transmitted by the comparator 141 to the operational amplifier circuit 15 is a low level.

[0095] D25, for the operational amplifier circuit 15, due to the existence of the first inverter 152, when the first level is transmitted to the amplifier 151, Figure 2When the voltage at point M in the circuit is higher than the voltage at point N, the amplifier 151 reduces the voltage at the first node A1. The supply current ireg increases as the voltage at the first node A1 decreases.

[0096] In the first stage of loop establishment, each circuit repeats the above work until Figure 2 The voltage at point F is higher than the reference voltage vref.

[0097] The second stage of the loop establishment, that is, from the voltage at point F being higher than the reference voltage vref to the peak voltage at point F being twice the reference voltage vref:

[0098] The working process of the circuit structure is basically the same in each cycle of this stage, so we will take one cycle as an example to illustrate:

[0099] P11. For the charging circuit 11, the first switch element 112 is turned on by the first pulse signal of the current pulse cycle, ie, the low-level pulse signal. The second switch element 113 is turned off by the first pulse signal of the current pulse cycle.

[0100] P12. For the discharge circuit 16, the third switch element 161 is turned off under the first pulse signal of the current pulse cycle.

[0101] P13. For the power supply circuit 12, when the first switch element 112 is turned on, its power supply current ireg is transmitted to the sawtooth wave generating circuit 13 through the charging circuit 11, the fourth capacitor 132 starts to charge, and the third target circuit 131 generates a first voltage corresponding to the power supply current ireg, that is, Figure 2 The voltage corresponding to point F.

[0102] P14. For the sawtooth wave generating circuit 13, the fourth capacitor 132 is charged under the supply current, and the third target circuit 131 generates a linear rising end waveform of the sawtooth wave.

[0103] P15. For the comparison circuit 14, since the supply current has increased sufficiently, the voltage at point F is higher than the reference voltage vref, and the first level transmitted by the comparator 141 to the operational amplifier circuit 15 is a high level.

[0104] P16. For the operational amplifier circuit 15, due to the presence of the first inverter 152, when the first level is transmitted to the amplifier 151, Figure 2 When the voltage at point M in the circuit is lower than the voltage at point N, the amplifier 151 increases the voltage at the first node A1. The supply current ireg decreases as the voltage at the first node A1 increases.

[0105] After the first pulse signal of the current pulse cycle is sent, and the second pulse signal of the current pulse cycle is sent, the working process of each circuit is as follows:

[0106] P21. For the charging circuit 11, the first switch element 112 is turned off under the second pulse signal of the current pulse cycle, that is, the high-level pulse signal. The second switch element 113 is turned on under the second pulse signal of the current pulse cycle.

[0107] P22: For the discharge circuit 16, the third switch element 161 is turned on under the second pulse signal of the current pulse cycle, and pulls down the fourth capacitor 132 in the sawtooth wave generating circuit 13 to the target potential end.

[0108] P23. For the sawtooth wave generating circuit 13, the voltage of the fourth capacitor 132 is pulled down to the target potential end by the turning on of the third switch element 161, and the third target circuit 131 generates a linear falling end waveform of the sawtooth wave.

[0109] P24. For the comparison circuit 14, since the voltage of the third target circuit 131 is pulled down, the voltage at point F is lower than the reference voltage vref, and the first level transmitted by the comparator 141 to the operational amplifier circuit 15 is a low level.

[0110] P25. For the operational amplifier circuit 15, due to the presence of the first inverter 152, when the first level is transmitted to the amplifier 151, Figure 2 The voltage at point M in the circuit is higher than the voltage at point N, and amplifier 151 decreases the voltage at first node A1. The supply current ireg increases as the voltage at first node A1 decreases. The decrease in the voltage at first node A1 during the current pulse cycle is greater than the increase in the voltage at first node A1 during the previous pulse cycle. This occurs until the voltage at point F exceeds the reference voltage vref for the same amount of time that point F remains below the reference voltage vref, meaning that the peak value of the reference voltage at point F reaches twice the reference voltage vref. This completes the voltage modulation at first node A1, and the supply current remains stable.

[0111] In the second stage of loop establishment, each circuit repeats the above operation in each cycle until the peak voltage at point F is twice the reference voltage vref.

[0112] After the second phase of loop establishment is completed, it enters the stable working process:

[0113] When the first node A1 is adjusted to a stable value, the supply current ireg remains stable, and the peak voltage at point F is twice the reference voltage vref. During the stable operating phase, the operating logic of each circuit is as follows: If the peak voltage at point F is lower than twice the reference voltage vref, the average value at point N is lower than that at point M. In this case, the voltage at first node A1 is adjusted to decrease, ultimately causing the average value of the maximum voltage at point F to equal the reference voltage vref. Conversely, if the peak voltage at point F is higher than twice the reference voltage vref, the average value at point N is higher than that at point M. In this case, the voltage at first node A1 is adjusted to increase, ultimately causing the average value of the minimum voltage at point F to also equal the reference voltage vref.

[0114] In summary, Figure 2 From the working process of the circuit structure shown in FIG, the specific working principle of this circuit structure is:

[0115] exist Figure 2 When the voltage at point F in the circuit is lower than the reference voltage vref, the supply current ireg starts to increase from zero current and is transmitted to the sawtooth wave generating circuit 13. After the supply current ireg is transmitted to the sawtooth wave generating circuit 13, the fourth capacitor 132 begins to charge until the discharge circuit 16 directly lowers the voltage at point F in response to the second pulse signal, i.e., the high pulse.

[0116] If the current pulse cycle is the first pulse cycle, the corresponding first voltage at point F is lower than the reference voltage vref throughout the entire charging process, so the supply current ireg increases throughout the charging process. When the second pulse signal, i.e., a high pulse, arrives, the voltage at point F is pulled down but still lower than the reference voltage vref, and the supply current ireg continues to increase. When the first pulse signal of the next pulse cycle arrives, the charging circuit 11 turns on, and the second power supply circuit supplies power to the sawtooth wave generating circuit 13. Point F continues to charge from zero potential, and the charging current at this time continues to increase from the value of the previous pulse cycle. This cycle repeats for several cycles, and point F remains lower than the reference voltage vref throughout the entire cycle, so the supply current ireg continues to increase until the charging within one pulse cycle reaches the point where point F is higher than the reference voltage vref. Once the first voltage at point F is higher than the reference voltage vref, the supply current ireg begins to decrease. As long as the time when the first voltage at point F is higher than the reference voltage vref is less than the time when the first voltage at point F is lower than the reference voltage vref, the time when the supply current ireg increases in each pulse cycle is longer than the time when it decreases, until the time when the supply current ireg increases is equal to the time when it decreases. At this time, the time when the first voltage at point F is higher than the reference voltage vref is equal to the time when point F is lower than vref. The circuit establishment process is completed and enters a steady state, that is, the voltage at point F is higher than the reference voltage vref for half of the entire pulse cycle and lower than the reference voltage vref for half of the time, and the time when the supply current ireg increases is equal to the time when it decreases, that is, the average value of ireg remains unchanged, thereby achieving constant current charging.

[0117] In the circuit structure provided by the embodiment of the present invention, the charging circuit transmits the supply current of the power supply circuit to the sawtooth wave generating circuit under the first pulse signal. The comparison circuit compares the voltage of the sawtooth wave generating circuit with the reference voltage and outputs a first level to the operational amplifier circuit. The operational amplifier circuit adjusts the supply current of the power supply circuit based on the first level. After the first pulse signal is transmitted, the discharge circuit adjusts the voltage of the sawtooth wave generating circuit under the second pulse signal. The comparison circuit transmits the first level to the operational amplifier circuit based on the voltage in the sawtooth wave generating circuit adjusted by the discharge circuit. The operational amplifier circuit adjusts the supply current of the power supply circuit based on the first level. It can be seen that the solution provided by the embodiment of the present invention adjusts the supply current of the power supply circuit by feeding back a level related to the voltage of the sawtooth wave generating circuit to the operational amplifier circuit through the comparison circuit, so that the supply current is maintained in a stable state, thereby enabling the sawtooth wave generating circuit to generate a sawtooth wave with a stable waveform under a stable supply current. Therefore, the solution provided by the embodiment of the present invention can achieve precise control of the sawtooth wave waveform and reduce sawtooth wave waveform deviation.

[0118] Furthermore, according to the above method embodiment, another embodiment of the present invention further provides an electronic device, the electronic device comprising: Figure 1or Figure 2 The circuit structure.

[0119] The embodiment of the present invention does not specifically limit the type of the electronic device. Exemplarily, the electronic device is a PWM (Pulsewidth modulation) driving device or a PWM display device.

[0120] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0121] It is understood that the relevant features of the above methods and devices can be referenced to each other. In addition, the terms "first" and "second" in the above embodiments are used to distinguish between the embodiments, and do not represent the advantages and disadvantages of the embodiments.

[0122] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A circuit structure for sawtooth waveform control, characterized in that: The circuit structure includes: a charging circuit, a discharging circuit, a power supply circuit, a sawtooth wave generating circuit, a comparison circuit, and an operational amplifier circuit; The charging circuit is configured to transmit the power supply current of the power supply circuit to the sawtooth wave generating circuit under a first pulse signal; The discharge circuit is used to adjust the voltage of the sawtooth wave generating circuit under the second pulse signal, wherein the power supply circuit is disconnected from the sawtooth wave generating circuit when the second pulse signal is applied; The comparison circuit is configured to compare the voltage of the sawtooth wave generating circuit with a reference voltage and output a first level to the operational amplifier circuit; The operational amplifier circuit is configured to adjust a power supply current of the power supply circuit based on the first level; The discharge circuit includes a third switching element; The first end of the third switch element is connected to the seventh node, the second end is connected to the target potential end, and the third end is connected to the eighth node; the seventh node is connected to the charging circuit and the sawtooth wave generating circuit respectively; the eighth node is used to receive the first pulse signal or the second pulse signal; The third switch element is used to turn on under the second pulse signal and pull down the voltage of the sawtooth wave generating circuit to the target potential end; and to turn off under the first pulse signal.

2. The circuit structure according to claim 1, wherein: The power supply circuit includes a first capacitor and a target element; The first end of the first capacitor is connected to a preset power supply, and the second end is connected to a first node; the first end of the target element is connected to the preset power supply, the second end is connected to the charging circuit, and the third end is connected to the first node; the first node is connected to the operational amplifier circuit.

3. The circuit structure according to claim 2, wherein: the operational amplifier circuit being configured to reduce the voltage of the first node when the first level is a low level, wherein the supply current transmitted by the target component to the charging circuit increases as the voltage of the first node decreases; or, The operational amplifier circuit is configured to increase the voltage of the first node when the first level is a high level, wherein the supply current transmitted by the target component to the charging circuit decreases as the voltage of the first node increases.

4. The circuit structure according to claim 1, wherein: The operational amplifier circuit includes an amplifier, a first inverter, a first target circuit and a second target circuit; The first input terminal of the amplifier is connected to the output terminal of the first inverter through the first target circuit, the second input terminal is connected to the second node through the second target circuit, and the output terminal is connected to the power supply circuit; the input terminal of the first inverter is connected to the second node; and the second node is connected to the comparison circuit; the first inverter is configured to invert the first level when receiving the first level transmitted by the comparison circuit to the second node; The amplifier is configured to perform an amplification operation based on the first level inverted by the first inverter and the first level transmitted by the second target circuit, and adjust the power supply current of the power supply circuit based on the operation result.

5. The circuit structure according to claim 4, characterized in that: The first target circuit includes a first resistor and a second capacitor; The first end of the first resistor is connected to the output end of the first inverter, and the second end is connected to the third node; the first end of the second capacitor is connected to the third node, and the second end is connected to the target potential end; the third node is connected to the first input end of the amplifier.

6. The circuit structure according to claim 4, characterized in that: The second target circuit includes a second resistor and a third capacitor; The first end of the second resistor is connected to the second node, and the second end is connected to the fourth node; the first end of the third capacitor is connected to the fourth node, and the second end is connected to the target potential end; the fourth node is connected to the second input end of the amplifier.

7. The circuit structure according to any one of claims 4 to 6, characterized in that: The operational amplifier circuit further includes a first diode and a second diode; The first diode and the second diode are arranged between the first target circuit and the second target circuit; wherein, the cathode of the first diode is connected to the second target circuit, and the anode is connected to the first target circuit; the cathode of the second diode is connected to the first target circuit, and the anode is connected to the second target circuit.

8. The circuit structure according to claim 1, wherein: The charging circuit includes a second inverter, a first switching element and a second switching element; The first end of the first switching element is connected to the fifth node, the second end is connected to the sawtooth wave generating circuit, and the third end is connected to the sixth node; the first end of the second switching element is connected to the fifth node, the second end is connected to the target potential terminal, and the third end is connected to the output terminal of the second inverter; the input terminal of the second inverter is connected to the sixth node; The fifth node is connected to the power supply circuit, and the sixth node is used to receive the first pulse signal or the second pulse signal; the first switching element is configured to be turned on under the first pulse signal and transmit the power supply current transmitted by the power supply circuit received by the fifth node to the sawtooth wave generating circuit; Under the second pulse signal, turn off; The second inverter is configured to invert the first pulse signal upon receiving the first pulse signal, and transmit the inverted first pulse signal to the second switching element; Upon receiving the second pulse signal, inverting the second pulse signal and transmitting the inverted second pulse signal to the second switching element; The second switch element is configured to be turned off under the inverted first pulse signal and turned on under the inverted second pulse signal.

9. The circuit structure according to claim 1, wherein: The sawtooth wave generating circuit includes: a third target circuit and a fourth capacitor; The first end of the third target circuit is connected to the charging circuit and the discharging circuit respectively, and the second end is connected to the ninth node; the first end of the fourth capacitor is connected to the ninth node, and the second end is connected to the target potential end; the ninth node is connected to the comparison circuit.

10. The circuit structure according to claim 1, wherein: The comparison circuit includes a comparator; The positive phase input terminal of the comparator is connected to the sawtooth wave generating circuit, and the negative phase input terminal is connected to the circuit providing the reference voltage; The comparator is configured to transmit the first level to the operational amplifier circuit based on the voltage of the sawtooth wave generating circuit and the reference voltage.

11. An electronic device, characterized in that: The electronic device comprises: the circuit structure for sawtooth waveform control according to any one of claims 1 to 10.

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