Oscillator circuit, integrated circuit, and electronic device
By using a constant current source and a reference voltage in the oscillator circuit, the instability problem of the PVT characteristics of traditional oscillator circuits is solved, and the stability and adjustability of frequency and duty cycle are achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHENGDU SHIDAI SUXIN TECH CO LTD
- Filing Date
- 2025-08-14
- Publication Date
- 2026-07-21
AI Technical Summary
Traditional oscillator circuits do not perform well in terms of PVT characteristics, which makes their frequency stability highly susceptible to environmental factors.
The design employs at least two RC charging/discharging circuits, a comparator circuit, and a trigger circuit. A constant current source is used to charge the capacitor. The trigger circuit controls the switching devices to turn on and off based on the output signal of the comparator circuit. Combined with a reference voltage, precise charging/discharging conversion is performed to ensure the stability of frequency and duty cycle.
By maintaining the stability of the oscillator period and frequency when PVT conditions change, the sensitivity to the external environment is reduced, and the adjustability and accuracy of the frequency and duty cycle are achieved.
Smart Images
Figure CN224538165U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electronic technology, and more specifically, to an oscillator circuit, integrated circuit, and electronic device. Background Technology
[0002] In modern electronic systems, oscillator circuits, as core components capable of generating periodic signals, are widely used in various fields such as communications, broadcasting, television, radar, instrumentation, and automatic control. With the continuous development of electronic technology, the performance requirements for oscillator circuits are also increasing, especially in terms of frequency stability and duty cycle adjustment. Frequency-adjustable and duty-cycle-adjustable oscillator circuits have emerged as a result, becoming one of the key technologies to meet diverse application needs.
[0003] Traditional oscillators, such as ring oscillators, have limitations in frequency adjustment and duty cycle control, especially in their poor performance in PVT (Process-Voltage-Temperature) characteristics. Their period is limited by the delay of each stage inverter, and their frequency stability is greatly affected by environmental factors. Utility Model Content
[0004] The main objective of this application is to provide an oscillator circuit, integrated circuit, and electronic device to at least solve the problem in the prior art where the poor performance of oscillator circuits in terms of PVT characteristics leads to significant influence of environmental factors on frequency stability.
[0005] To achieve the above objectives, according to one aspect of this application, an oscillator circuit is provided, comprising: at least two RC charging and discharging circuits, each RC charging and discharging circuit including a constant current source, a capacitor, and a switching device, wherein the output terminal of the constant current source is connected to a first terminal of the capacitor and a first terminal of the switching device, respectively; at least two comparator circuits, wherein the first input terminals of the comparator circuits are connected one-to-one with the first terminals of the capacitors in the RC charging and discharging circuits, and the second input terminals of the comparator circuits are used to receive a reference voltage; and a trigger circuit, including a first input terminal, a second input terminal, a first output terminal, and a second output terminal, wherein the first input terminal of the trigger circuit is connected to the output terminal of one of the comparator circuits, the second input terminal of the trigger circuit is connected to the output terminal of the other comparator circuit, the first output terminal of the trigger circuit is connected to the control terminal of the switching device in one of the RC charging and discharging circuits, and the second output terminal of the trigger circuit is connected to the control terminal of the switching device in the other RC charging and discharging circuit, wherein the trigger circuit outputs a first level signal or a second level signal according to the output signal of the comparator circuit, wherein the first level signal is a signal for controlling the switching device to turn on, and the second level signal is a signal for controlling the switching device to turn off.
[0006] Optionally, the oscillator circuit further includes an inverter, the input terminal of which is connected to the first output terminal or the second output terminal of the trigger circuit, and the output terminal of the inverter is the output terminal of the oscillator circuit.
[0007] Optionally, the two comparison circuits are a first comparison circuit and a second comparison circuit, and the trigger circuit includes an RS flip-flop, which includes a first NOR gate and a second NOR gate; the first input terminal of the first NOR gate is connected to the output terminal of the first comparison circuit, and the second input terminal of the first NOR gate is connected to the output terminal of the second NOR gate; the first input terminal of the second NOR gate is connected to the output terminal of the second comparison circuit, and the second input terminal of the second NOR gate is connected to the output terminal of the first NOR gate.
[0008] Optionally, the two RC charging and discharging circuits are a first RC charging and discharging circuit and a second RC charging and discharging circuit. The first terminal of the capacitor in the first RC charging and discharging circuit is connected to the first input terminal of the first comparator circuit, and the first terminal of the capacitor in the second RC charging and discharging circuit is connected to the first input terminal of the second comparator circuit. Both the first input terminal of the first comparator circuit and the first input terminal of the second comparator circuit are positive input terminals. The second input terminal of the first comparator circuit and the second input terminal of the second comparator circuit are respectively used to receive the reference voltage. Both the second input terminal of the first comparator circuit and the second input terminal of the second comparator circuit are negative input terminals. The output terminal of the first NOR gate is connected to the control terminal of the switching device in the second RC charging and discharging circuit, and the output terminal of the second NOR gate is connected to the control terminal of the switching device in the first RC charging and discharging circuit.
[0009] Optionally, the two RC charging and discharging circuits are a first RC charging and discharging circuit and a second RC charging and discharging circuit. The first terminal of the capacitor in the first RC charging and discharging circuit is connected to the first input terminal of the first comparator circuit, and the first terminal of the capacitor in the second RC charging and discharging circuit is connected to the first input terminal of the second comparator circuit. Both the first input terminal of the first comparator circuit and the first input terminal of the second comparator circuit are negative input terminals. The second input terminal of the first comparator circuit and the second input terminal of the second comparator circuit are respectively used to receive the reference voltage. Both the second input terminal of the first comparator circuit and the second input terminal of the second comparator circuit are positive input terminals. The output terminal of the first NOR gate is connected to the control terminal of the switching device in the first RC charging and discharging circuit, and the output terminal of the second NOR gate is connected to the control terminal of the switching device in the second RC charging and discharging circuit.
[0010] Optionally, the input terminal of the constant current source is used to connect to a power supply, the second terminal of the capacitor is grounded, and the second terminal of the switching device is grounded.
[0011] Optionally, the two RC charging and discharging circuits are respectively a first RC charging and discharging circuit and a second RC charging and discharging circuit. The first RC charging and discharging circuit includes a first constant current source, a first capacitor, and a first switching device. There are multiple first capacitors connected in parallel. The first RC charging and discharging circuit further includes multiple first switching structures. The first terminal of each first switching structure is connected to the second terminal of the first capacitor in a corresponding manner. The second terminal of each first switching structure is grounded. The control terminal of each first switching structure is used to receive a first signal.
[0012] Optionally, the two RC charging and discharging circuits are respectively a first RC charging and discharging circuit and a second RC charging and discharging circuit. The second RC charging and discharging circuit includes a second constant current source, a second capacitor, and a second switching device. There are multiple second capacitors connected in parallel. The second RC charging and discharging circuit also includes multiple second switching structures. The first terminal of each second switching structure is connected to the second terminal of the second capacitor in a one-to-one correspondence. The second terminal of each second switching structure is grounded. The control terminal of each second switching structure is used to receive a second signal.
[0013] According to another aspect of this application, an integrated circuit is provided, comprising: any of the oscillator circuits described above.
[0014] According to another aspect of this application, an electronic device is provided, including the aforementioned integrated circuit.
[0015] Using the technical solution of this application, the oscillator circuit includes at least two RC charging and discharging circuits, at least two comparator circuits, and a trigger circuit. The RC charging and discharging circuit includes a constant current source, a capacitor, and a switching device. The output terminal of the constant current source is connected to the first terminal of the capacitor and the first terminal of the switching device, respectively. The first input terminal of the comparator circuit is connected to the first terminal of the capacitor in the RC charging and discharging circuit in a one-to-one correspondence. The second input terminal of the comparator circuit is used to receive a reference voltage. The two input terminals of the trigger circuit are connected to the output terminals of the two comparator circuits, respectively. The two output terminals of the trigger circuit are connected to the control terminals of the switching devices in the two RC charging and discharging circuits, respectively. The trigger circuit outputs a level signal according to the output signal of the comparator circuit to control the switching devices to turn on or off. The oscillator circuit of this application uses a constant current source to charge the capacitor. A constant current source means that the amount of charge passing through the capacitor is fixed within a given time and is not affected by changes in the power supply voltage. The charging time of the capacitor is determined only by the capacitance value and the current magnitude, ensuring that the charging time remains consistent even when PVT conditions change, thereby guaranteeing high stability of the oscillator's period and frequency. The trigger circuit responds quickly to the output signal of the comparator circuit and outputs a control signal to turn the switching device on or off, ensuring accurate and timely switching of the oscillator period. The use of the comparator circuit in conjunction with the reference voltage enables the trigger circuit to accurately trigger the charging and discharging transition when the capacitor voltage reaches a specific threshold. This reduces the uncertainty of delay and transition time, ensuring the stability and accuracy of the oscillator signal. Since the oscillator period is mainly determined by the magnitude of the current and the capacitance value inside the circuit, the sensitivity of the oscillator to the external environment, such as power supply fluctuations and temperature changes, is reduced, ensuring good frequency stability of the frequency-adjustable and duty-cycle-adjustable oscillator under various environmental conditions. Attached Figure Description
[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:
[0017] Figure 1 A schematic diagram of the circuit structure of an oscillator circuit provided in an embodiment of this application is shown;
[0018] Figure 2 A schematic diagram of the circuit structure of another oscillator circuit provided in an embodiment of this application is shown;
[0019] Figure 3 An embodiment provided according to this application is shown. Figure 1 The waveform diagram of each node when the oscillator circuit is working.
[0020] The above figures include the following reference numerals:
[0021] 10. RC charging and discharging circuit; 11. Constant current source; 12. Capacitor; 13. Switching device; 14. Comparator circuit; 15. Trigger circuit; 16. Inverter; 141. First comparator circuit; 142. Second comparator circuit; 101. First RC charging and discharging circuit; 102. Second RC charging and discharging circuit; 17. RS flip-flop; 171. First NOR gate; 172. Second NOR gate; 111. First constant current source; 121. First capacitor; 131. First switching device; 18. First switching structure; 112. Second constant current source; 122. Second capacitor; 132. Second switching device; 19. Second switching structure. Detailed Implementation
[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.
[0023] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.
[0024] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.
[0025] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.
[0026] It should be understood that when an element (such as a layer, film, region, or substrate) is described as being "on" another element, the element may be directly on the other element, or there may be an intermediate element present. Furthermore, in the specification and claims, when an element is described as being "connected" to another element, the element may be "directly connected" to the other element, or "connected" to the other element via a third element.
[0027] As described in the background section, the oscillator circuits in the prior art have poor performance in terms of PVT characteristics, resulting in frequency stability being greatly affected by environmental factors. In order to solve the above problems, the embodiments of this application provide an oscillator circuit, integrated circuit and electronic device.
[0028] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.
[0029] This application provides an oscillator circuit, such as... Figure 1 and Figure 2 As shown, it includes:
[0030] At least two RC charging and discharging circuits 10, each RC charging and discharging circuit 10 including a constant current source 11, a capacitor 12 and a switching device 13, wherein the output terminal of the constant current source 11 is connected to the first terminal of the capacitor 12 and the first terminal of the switching device 13 respectively.
[0031] Specifically, switching devices may include transistors.
[0032] In practical applications, those skilled in the art can flexibly select the current value of the constant current source and the capacitance value of the capacitor according to actual needs, and this application does not impose specific restrictions on this.
[0033] At least two comparison circuits 14, the first input terminal of the comparison circuit 14 is connected to the first terminal of the capacitor 12 in the RC charging and discharging circuit 10 in a one-to-one correspondence, and the second input terminal of the comparison circuit 14 is used to receive the reference voltage.
[0034] Specifically, the comparison circuit may include a comparator.
[0035] In practical applications, those skilled in the art can set the above-mentioned reference voltage based on experience, or it can be obtained through multiple experiments; this application does not impose specific limitations in this regard. In the embodiments of this application, the above-mentioned reference voltage is 1V.
[0036] The trigger circuit 15 includes a first input terminal, a second input terminal, a first output terminal, and a second output terminal. The first input terminal of the trigger circuit 15 is connected to the output terminal of one of the comparator circuits 14, and the second input terminal of the trigger circuit 15 is connected to the output terminal of the other comparator circuit 14. The first output terminal of the trigger circuit 15 is connected to the control terminal of the switching device 13 in one of the RC charging and discharging circuits 10, and the second output terminal of the trigger circuit 15 is connected to the control terminal of the switching device 13 in the other RC charging and discharging circuit 10. The trigger circuit 15 outputs a first-level signal or a second-level signal according to the output signal of the comparator circuit. The first-level signal is a signal to control the switching device 13 to be turned on, and the second-level signal is a signal to control the switching device 13 to be turned off.
[0037] In the above embodiments, the oscillator circuit includes at least two RC charging and discharging circuits, at least two comparator circuits, and a trigger circuit. The RC charging and discharging circuit includes a constant current source, a capacitor, and a switching device. The output terminal of the constant current source is connected to the first terminal of the capacitor and the first terminal of the switching device, respectively. The first input terminal of the comparator circuit is connected to the first terminal of the capacitor in the RC charging and discharging circuit, respectively. The second input terminal of the comparator circuit is used to receive a reference voltage. The two input terminals of the trigger circuit are connected to the output terminals of the two comparator circuits, respectively. The two output terminals of the trigger circuit are connected to the control terminals of the switching devices in the two RC charging and discharging circuits, respectively. The trigger circuit outputs a level signal according to the output signal of the comparator circuit to control the switching devices to turn on or off. The oscillator circuit of this application uses a constant current source to charge the capacitor. A constant current source means that the amount of charge passing through the capacitor is fixed within a given time and is not affected by changes in the power supply voltage. The charging time of the capacitor is determined only by the capacitance value and the current magnitude, ensuring that the charging time remains consistent even when PVT conditions change, thereby guaranteeing high stability of the oscillator's period and frequency. The trigger circuit responds quickly to the output signal of the comparator circuit and outputs a control signal to turn the switching device on or off, ensuring accurate and timely switching of the oscillator period. The use of the comparator circuit in conjunction with the reference voltage enables the trigger circuit to accurately trigger the charging and discharging transition when the capacitor voltage reaches a specific threshold. This reduces the uncertainty of delay and transition time, ensuring the stability and accuracy of the oscillator signal. Since the oscillator period is mainly determined by the magnitude of the current and the capacitance value inside the circuit, the sensitivity of the oscillator to the external environment, such as power supply fluctuations and temperature changes, is reduced, ensuring good frequency stability of the frequency-adjustable and duty-cycle-adjustable oscillator under various environmental conditions.
[0038] Specifically, by controlling the current magnitude and capacitance value of the constant current sources in the two RC charging and discharging circuits, the frequency and duty cycle of the oscillator can be adjusted independently. This design allows users to flexibly adjust the frequency of the output signal and the ratio of the high to low level durations according to specific application requirements, thereby achieving adjustable duty cycle.
[0039] Specifically, in the RC charging and discharging circuit, the capacitor and the constant current source work together. The capacitor charges under the action of a constant current. When the voltage across the capacitor reaches the reference voltage set by the comparator circuit, the trigger circuit receives a signal from the comparator circuit, thereby changing the state of the switching device and starting the capacitor's discharge process. This process repeats continuously, forming a stable oscillation waveform. By adjusting the current value of the constant current source or the size of the capacitor, the oscillation frequency of the circuit can be changed, overcoming the limitations of traditional oscillators in frequency adjustment. Furthermore, the use of a comparator circuit combined with a reference voltage ensures high precision in the oscillation frequency, maintaining frequency stability even under different process conditions, voltage fluctuations, and temperature environments. This is achieved through the precise control of the constant current source and the sensitive response of the comparator circuit.
[0040] In one alternative, such as Figure 1 and Figure 2 As shown, the oscillator circuit further includes an inverter 16. The input terminal of the inverter 16 is connected to either the first or second output terminal of the trigger circuit 15, and the output terminal of the inverter 16 is the output terminal of the oscillator circuit. In this embodiment, the inverter can be used as a signal shaping and amplification tool to ensure that the waveform quality of the signal output from the trigger circuit at the output terminal of the oscillator circuit is good. The inverter can also adjust the level of the output signal of the oscillator circuit to match the input requirements of other parts of the system or the target circuit. For example, if the signal level output by the trigger circuit does not match the operating level of the system, the inverter can perform level conversion to ensure that the output signal can be correctly identified and processed.
[0041] In one exemplary embodiment, such as Figure 1 and Figure 2As shown, the two comparison circuits 14 are a first comparison circuit 141 and a second comparison circuit 142, respectively. The trigger circuit 15 includes an RS flip-flop 17, which includes a first NOR gate 171 and a second NOR gate 172. The first input terminal of the first NOR gate 171 is connected to the output terminal of the first comparison circuit 141, and the second input terminal of the first NOR gate 171 is connected to the output terminal of the second NOR gate 172. The first input terminal of the second NOR gate 172 is connected to the output terminal of the second comparison circuit 142, and the second input terminal of the second NOR gate 172 is connected to the output terminal of the first NOR gate 171. In this embodiment, the RS flip-flop receives signals from two comparator circuits. When the comparator circuit detects that the capacitor voltage has reached the reference voltage, it sends a signal to the RS flip-flop. The special logic structure of the RS flip-flop (i.e., the flip-flop state changes when either the R or S terminal is high) ensures precise control of the charging and discharging process, that is, switching the charging and discharging state of the capacitor at appropriate times, thereby maintaining the stable operation of the oscillator. Furthermore, the RS flip-flop is a basic storage unit that can maintain or switch the logic state until the next valid R or S signal is received. This means that once the oscillator circuit starts working, the RS flip-flop will stably output high and low level signals. This stable output is crucial to the reliability of the entire circuit.
[0042] Specifically, in the RS flip-flop, two NOR gates can also be replaced with two NAND gates, and this application does not impose any specific restrictions on this.
[0043] In other embodiments, such as Figure 1 and Figure 2As shown, the two RC charging and discharging circuits 10 are a first RC charging and discharging circuit 101 and a second RC charging and discharging circuit 102, respectively. The first end of the capacitor 12 in the first RC charging and discharging circuit 101 is connected to the first input terminal of the first comparator circuit 141, and the first end of the capacitor 12 in the second RC charging and discharging circuit 102 is connected to the first input terminal of the second comparator circuit 142. Both the first input terminals of the first comparator circuit 141 and the second input terminal of the second comparator circuit 142 are positive input terminals. The second input terminals of the first comparator circuit 141 and the second input terminals of the second comparator circuit 142 are used to receive the reference voltage, and both the second input terminals of the first comparator circuit 141 and the second input terminal of the second comparator circuit 142 are negative input terminals. The output terminal of the first NOR gate 171 is connected to the control terminal of the switching device 13 in the second RC charging and discharging circuit 102, and the output terminal of the second NOR gate 172 is connected to the control terminal of the switching device in the first RC charging and discharging circuit 101. In this embodiment, the output of the first NOR gate is connected to the control terminal of the switching device in the second RC charging and discharging circuit, while the output of the second NOR gate is connected to the control terminal of the switching device in the first RC charging and discharging circuit. This interlocking mechanism ensures that at any given time, only one RC charging and discharging circuit is charging while the other is discharging, reducing the situation of simultaneous charging or discharging and further maintaining the normal operation of the oscillator and the periodicity and stability of the output signal.
[0044] Specifically, Figure 1 and Figure 2 In the circuit, the positive input terminal of the first comparator circuit 141 is point P, the positive input terminal of the second comparator circuit 142 is point N, the output terminal of the first comparator circuit 141 is point R, the output terminal of the second comparator circuit 142 is point S, the output terminal of the first NOR gate 171 is point Q, the output terminal of the second NOR gate 172 is point QN, and CLK is the output signal of the oscillator circuit.
[0045] Specifically, Figure 3 for Figure 1 The waveforms of each node in the oscillator circuit during operation are shown. For example... Figure 2As shown, the oscillator circuit operates as follows: Initially, points P (the positive input of the first comparator circuit), N (the positive input of the second comparator circuit), R (the output of the first comparator circuit), and S (the output of the second comparator circuit) are all at low levels, while point Q (the output of the first NOR gate) is at a high level, and point QN (the output of the second NOR gate) is at a low level. The constant current source in the first RC charging / discharging circuit begins charging the capacitor in the first RC charging / discharging circuit. When the voltage at point P exceeds the reference voltage, the level at point R flips to high, and the level at point Q... When the voltage at point P flips to low, the voltage at point QN flips to high, and the switching device in the first RC charging and discharging circuit begins to discharge. When the voltage at point P is less than the reference voltage, the voltage at point R flips to low, completing the first half of a cycle. Simultaneously, the constant current source in the second RC charging and discharging circuit charges the capacitor in the second RC charging and discharging circuit. When the voltage at point N is greater than the reference voltage, the voltage at point S flips to high, the voltage at point QN flips to low, and the voltage at point Q flips to high, completing the second half of a cycle. CLK is the output signal of the oscillator circuit.
[0046] Specifically, during the operating cycle of the oscillator circuit, the constant current source is always working. When the switching device is turned on, the capacitor begins to discharge. The capacitor discharges very quickly and for a very short time.
[0047] From the working process of the oscillator circuit, the oscillator's working period T = ΔV*C1 / I1 + ΔV*C2 / I2, where ΔV = 1V (i.e., the reference voltage), and the duty cycle = (C1 / I1) / (C1 / I1 + C2 / I2). C1 is the capacitance value of the capacitor in the first RC charging and discharging circuit, I1 is the current value of the constant current source in the first RC charging and discharging circuit, C2 is the capacitance value of the capacitor in the second RC charging and discharging circuit, and I2 is the current value of the constant current source in the second RC charging and discharging circuit. According to the period formula and the duty cycle formula, changing the charging current and changing the size of the charging capacitor can change the period and the duty cycle. Therefore, to obtain an oscillator circuit with adjustable frequency and adjustable duty cycle, it is only necessary to change the charging current and the size of the capacitor.
[0048] As can be seen from the formula, the period of the oscillator circuit in this application is only related to the magnitude of the current source current and the capacitance value. Compared with the traditional ring oscillator, it has better PVT characteristics. The period of the traditional ring oscillator is related to the delay of each stage inverter.
[0049] According to some exemplary embodiments of this application, the two RC charging and discharging circuits are respectively a first RC charging and discharging circuit and a second RC charging and discharging circuit. In the first RC charging and discharging circuit, the first end of the capacitor is connected to the first input terminal of the first comparator circuit, and in the second RC charging and discharging circuit, the first end of the capacitor is connected to the first input terminal of the second comparator circuit. Both the first input terminal of the first comparator circuit and the first input terminal of the second comparator circuit are negative input terminals. The second input terminal of the first comparator circuit and the second input terminal of the second comparator circuit are respectively used to receive the reference voltage. Both the second input terminal of the first comparator circuit and the second input terminal of the second comparator circuit are positive input terminals. The output terminal of the first NOR gate is connected to the control terminal of the switching device in the first RC charging and discharging circuit, and the output terminal of the second NOR gate is connected to the control terminal of the switching device in the second RC charging and discharging circuit. In this embodiment, the output of the first NOR gate controls the switch of the first RC charging and discharging circuit, and the output of the second NOR gate controls the switch of the second RC charging and discharging circuit, forming an alternating charging and discharging mechanism. This means that in one cycle, when one circuit is charging, the other circuit is discharging, and then the roles are reversed and repeated. This mechanism ensures the continuous operation of the oscillator and avoids the possibility of two circuits charging and discharging at the same time, further enhancing the stability and reliability of the circuit.
[0050] According to some other exemplary embodiments of this application, the input terminal of the constant current source is connected to a power supply, the second terminal of the capacitor is grounded, and the second terminal of the switching device is grounded. In this embodiment, the input terminal of the constant current source is directly connected to the power supply, and the second terminals of the capacitor and the switching device are grounded. This simplifies the circuit layout, reduces interference, and further ensures better circuit stability and reliability.
[0051] In some of the alternative solutions of this application, such as Figure 2 As shown, the two RC charging and discharging circuits 10 are a first RC charging and discharging circuit 101 and a second RC charging and discharging circuit 102, respectively. The first RC charging and discharging circuit 101 includes a first constant current source 111, a first capacitor 121, and a first switching device 131. There are multiple first capacitors 121 connected in parallel. The first RC charging and discharging circuit 101 also includes multiple first switching structures 18, the first terminals of which are connected to the second terminals of the first capacitors 121 respectively. The second terminals of each first switching structure 18 are grounded, and the control terminals of each first switching structure 18 are used to receive a first signal. In this embodiment, the design of multiple first capacitors connected in parallel allows users to adjust the charging time of the circuit by selecting the number of capacitors participating in the charging and discharging, thereby indirectly adjusting the frequency and duty cycle of the oscillator.
[0052] Specifically, the first signal is used to control the on or off state of the first switching structure, which can be a transistor. The first signals corresponding to each first switching structure can be the same or different.
[0053] According to some further exemplary embodiments of this application, such as Figure 2 As shown, the two RC charging and discharging circuits 10 are a first RC charging and discharging circuit 101 and a second RC charging and discharging circuit 102, respectively. The second RC charging and discharging circuit 102 includes a second constant current source 112, a second capacitor 122, and a second switching device 132. There are multiple second capacitors 122 connected in parallel. The second RC charging and discharging circuit 102 also includes multiple second switching structures 19, the first terminals of which are connected to the second terminals of the second capacitors 122 respectively. The second terminals of each second switching structure 19 are grounded, and the control terminals of each second switching structure 19 are used to receive a second signal. In this embodiment, the design of multiple second capacitors connected in parallel allows users to adjust the charging time of the circuit by selecting the number of capacitors participating in the charging and discharging, thereby indirectly adjusting the frequency and duty cycle of the oscillator.
[0054] Specifically, the second signal is used to control the on or off state of the second switching structure, which can be a transistor. The second signals corresponding to each second switching structure can be the same or different.
[0055] In summary, this application utilizes a dual-channel RC charging / discharging circuit and a reference voltage for comparison, controlling the high and low levels of the square wave respectively; it uses an RS flip-flop to reset the voltage of the RC charging / discharging circuit; and it uses a constant current source to charge the capacitor. Compared with traditional ring oscillators, this application has better PVT characteristics; the oscillator circuit structure of this application allows for adjustment of frequency and duty cycle; and the oscillator circuit of this application uses a reference voltage for comparison, resulting in more accurate frequency.
[0056] This application also provides an integrated circuit, including any of the above-described oscillator circuits.
[0057] This application also provides an electronic device, including the integrated circuit described above.
[0058] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0059] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, article, or apparatus that includes that element.
[0060] As can be seen from the above description, the embodiments of this application achieve the following technical effects:
[0061] In the oscillator circuit of this application, the oscillator circuit includes at least two RC charging and discharging circuits, at least two comparator circuits, and a trigger circuit. The RC charging and discharging circuit includes a constant current source, a capacitor, and a switching device. The output terminal of the constant current source is connected to the first terminal of the capacitor and the first terminal of the switching device, respectively. The first input terminal of the comparator circuit is connected to the first terminal of the capacitor in the RC charging and discharging circuit in a one-to-one correspondence. The second input terminal of the comparator circuit is used to receive a reference voltage. The two input terminals of the trigger circuit are connected to the output terminals of the two comparator circuits, respectively. The two output terminals of the trigger circuit are connected to the control terminals of the switching devices in the two RC charging and discharging circuits, respectively. The trigger circuit outputs a level signal according to the output signal of the comparator circuit to control the switching devices to turn on or off. The oscillator circuit of this application uses a constant current source to charge the capacitor. A constant current source means that the amount of charge passing through the capacitor is fixed within a given time and is not affected by changes in the power supply voltage. The charging time of the capacitor is determined only by the capacitance value and the current magnitude, ensuring that the charging time remains consistent even when PVT conditions change, thereby guaranteeing high stability of the oscillator's period and frequency. The trigger circuit responds quickly to the output signal of the comparator circuit and outputs a control signal to turn the switching device on or off, ensuring accurate and timely switching of the oscillator period. The use of the comparator circuit in conjunction with the reference voltage enables the trigger circuit to accurately trigger the charging and discharging transition when the capacitor voltage reaches a specific threshold. This reduces the uncertainty of delay and transition time, ensuring the stability and accuracy of the oscillator signal. Since the oscillator period is mainly determined by the magnitude of the current and the capacitance value inside the circuit, the sensitivity of the oscillator to the external environment, such as power supply fluctuations and temperature changes, is reduced, ensuring good frequency stability of the frequency-adjustable and duty-cycle-adjustable oscillator under various environmental conditions.
[0062] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. An oscillator circuit, characterized in that, include: At least two RC charging and discharging circuits, each RC charging and discharging circuit including a constant current source, a capacitor and a switching device, wherein the output terminal of the constant current source is connected to the first terminal of the capacitor and the first terminal of the switching device, respectively. At least two comparator circuits, wherein the first input terminal of each comparator circuit is connected to the first terminal of the capacitor in the RC charging and discharging circuit, and the second input terminal of each comparator circuit is used to receive a reference voltage; A trigger circuit includes a first input terminal, a second input terminal, a first output terminal, and a second output terminal. The first input terminal of the trigger circuit is connected to the output terminal of one of the comparator circuits, and the second input terminal of the trigger circuit is connected to the output terminal of the other comparator circuit. The first output terminal of the trigger circuit is connected to the control terminal of the switching device in one of the RC charging and discharging circuits, and the second output terminal of the trigger circuit is connected to the control terminal of the switching device in the other RC charging and discharging circuit. The trigger circuit outputs a first level signal or a second level signal according to the output signal of the comparator circuit. The first level signal is a signal to control the switching device to turn on, and the second level signal is a signal to control the switching device to turn off.
2. The oscillator circuit according to claim 1, characterized in that, The oscillator circuit also includes: An inverter, the input terminal of which is connected to the first output terminal or the second output terminal of the trigger circuit, and the output terminal of which is the output terminal of the oscillator circuit.
3. The oscillator circuit according to claim 1, characterized in that, The two comparison circuits are a first comparison circuit and a second comparison circuit, respectively. The triggering circuit includes an RS flip-flop, which includes a first NOR gate and a second NOR gate; The first input terminal of the first NOR gate is connected to the output terminal of the first comparator circuit, and the second input terminal of the first NOR gate is connected to the output terminal of the second NOR gate. The first input terminal of the second NOR gate is connected to the output terminal of the second comparator circuit, and the second input terminal of the second NOR gate is connected to the output terminal of the first NOR gate.
4. The oscillator circuit according to claim 3, characterized in that, The two RC charging and discharging circuits are a first RC charging and discharging circuit and a second RC charging and discharging circuit, respectively. In the first RC charging and discharging circuit, the first end of the capacitor is connected to the first input terminal of the first comparator circuit, and in the second RC charging and discharging circuit, the first end of the capacitor is connected to the first input terminal of the second comparator circuit. Both the first input terminal of the first comparator circuit and the first input terminal of the second comparator circuit are positive input terminals. The second input terminal of the first comparator circuit and the second input terminal of the second comparator circuit are respectively used to receive the reference voltage, wherein the second input terminal of the first comparator circuit and the second input terminal of the second comparator circuit are both negative input terminals; The output terminal of the first NOR gate is connected to the control terminal of the switching device in the second RC charging and discharging circuit, and the output terminal of the second NOR gate is connected to the control terminal of the switching device in the first RC charging and discharging circuit.
5. The oscillator circuit according to claim 3, characterized in that, The two RC charging and discharging circuits are a first RC charging and discharging circuit and a second RC charging and discharging circuit, respectively. In the first RC charging and discharging circuit, the first end of the capacitor is connected to the first input terminal of the first comparator circuit, and in the second RC charging and discharging circuit, the first end of the capacitor is connected to the first input terminal of the second comparator circuit. Both the first input terminal of the first comparator circuit and the first input terminal of the second comparator circuit are negative input terminals. The second input terminal of the first comparator circuit and the second input terminal of the second comparator circuit are respectively used to receive the reference voltage, wherein the second input terminal of the first comparator circuit and the second input terminal of the second comparator circuit are both positive input terminals; The output terminal of the first NOR gate is connected to the control terminal of the switching device in the first RC charging and discharging circuit, and the output terminal of the second NOR gate is connected to the control terminal of the switching device in the second RC charging and discharging circuit.
6. The oscillator circuit according to claim 1, characterized in that, The input terminal of the constant current source is used to connect to the power supply, the second terminal of the capacitor is grounded, and the second terminal of the switching device is grounded.
7. The oscillator circuit according to claim 6, characterized in that, The two RC charging and discharging circuits are a first RC charging and discharging circuit and a second RC charging and discharging circuit, respectively. The first RC charging and discharging circuit includes a first constant current source, a first capacitor, and a first switching device; There are multiple first capacitors, and the multiple first capacitors are connected in parallel; The first RC charging and discharging circuit also includes: Multiple first switch structures are provided, with the first end of each first switch structure connected to the second end of the first capacitor in a corresponding manner. The second end of each first switch structure is grounded, and the control end of each first switch structure is used to receive a first signal.
8. The oscillator circuit according to claim 1, characterized in that, The two RC charging and discharging circuits are a first RC charging and discharging circuit and a second RC charging and discharging circuit, respectively. The second RC charging and discharging circuit includes a second constant current source, a second capacitor, and a second switching device; There are multiple second capacitors, and these multiple second capacitors are connected in parallel; The second RC charging and discharging circuit also includes: Multiple second switch structures are provided, with the first end of each second switch structure connected to the second end of the second capacitor in a one-to-one correspondence. The second end of each second switch structure is grounded, and the control end of each second switch structure is used to receive a second signal.
9. An integrated circuit, characterized in that, include: The oscillator circuit according to any one of claims 1 to 8.
10. An electronic device, characterized in that, Including the integrated circuit described in claim 9.