CN113395059A - Triangular wave generating circuit applied to analog jitter frequency technology - Google Patents
Triangular wave generating circuit applied to analog jitter frequency technology Download PDFInfo
- Publication number
- CN113395059A CN113395059A CN202110635605.8A CN202110635605A CN113395059A CN 113395059 A CN113395059 A CN 113395059A CN 202110635605 A CN202110635605 A CN 202110635605A CN 113395059 A CN113395059 A CN 113395059A
- Authority
- CN
- China
- Prior art keywords
- module
- resistor
- electrically connected
- voltage
- capacitor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K4/00—Generating pulses having essentially a finite slope or stepped portions
- H03K4/06—Generating pulses having essentially a finite slope or stepped portions having triangular shape
- H03K4/08—Generating pulses having essentially a finite slope or stepped portions having triangular shape having sawtooth shape
- H03K4/48—Generating pulses having essentially a finite slope or stepped portions having triangular shape having sawtooth shape using as active elements semiconductor devices
Landscapes
- Manipulation Of Pulses (AREA)
Abstract
The invention discloses a triangular wave generating circuit applied to an analog jitter frequency technology. The circuit comprises a voltage division module, a comparison control module, a charge-discharge module and a processing output module, wherein the comparison control module is connected between the voltage division module and the charge-discharge module, the voltage division module divides a power supply through a resistor to obtain a first reference voltage and a second reference voltage, the comparison control module is used for controlling and selecting the first reference voltage or the second reference voltage to be compared with the charge-discharge voltage generated by the charge-discharge module and outputting a control signal according to a comparison result, the charge-discharge module is used for periodically charging and discharging according to the control signal to output an initial voltage with a triangular waveform, and the processing output module is used for processing the initial voltage to obtain a triangular wave voltage with driving capability and adjustable precision. The invention has the advantages of simple structure, high precision, small occupied chip area and low development cost.
Description
Technical Field
The invention relates to the technical field of jitter frequency, in particular to a triangular wave generating circuit applied to an analog jitter frequency technology.
Background
The current commonly used frequency jittering circuits are divided into digital control and analog control: the principle of the digitally controlled frequency jittering circuit is that a counter counts the switching frequency to obtain a series of binary signals converted along with a clock to control the current for charging and discharging a capacitor, so that the jitter of the output frequency is realized, the continuity is poor, and the circuit area of a chip is large. The analog control frequency jittering circuit principle is that a low-frequency triangular wave signal is provided for a voltage-controlled oscillator, the voltage-controlled oscillator can change the output frequency along with the change of input voltage, and the continuity is good.
In the prior art, the generation method of the triangular wave signal in the analog control frequency jittering circuit is as follows: firstly, generating a square wave circuit; the square wave circuit is used for controlling the charging and discharging of the switched capacitor to generate triangular waves, as shown in figure 2. According to the design, reference signals VH and VL need to be provided externally, the mode of controlling the switched capacitor by the high-frequency square wave is difficult to control in the period precision of the triangular wave, the precision of the triangular wave cannot be guaranteed, meanwhile, the area of a chip occupied by the square wave generating circuit and the two comparators is large, and the development cost is increased.
Disclosure of Invention
Therefore, it is desirable to provide a triangular wave generating circuit applied to the analog dither technique, which has high waveform precision, small chip area and low cost.
The technical scheme provided by the invention for achieving the purpose is as follows:
a triangular wave generating circuit applied to an analog dither technology comprises a voltage division module, a comparison control module, a charge-discharge module and a processing output module, wherein the comparison control module is electrically connected between the voltage division module and the charge-discharge module, the processing output module is electrically connected with the charge-discharge module, the voltage division module divides a power supply through a resistor to obtain a first reference voltage and a second reference voltage, the comparison control module is used for controlling and selecting the first reference voltage or the second reference voltage to be compared with the charge-discharge voltage generated by the charge-discharge module and outputting a control signal according to a comparison result, the charge-discharge module is used for periodically charging and discharging according to the control signal to output an initial voltage with a triangular waveform, and the processing output module is used for processing the initial voltage, so as to obtain the triangular wave voltage with driving capability and adjustable precision.
The triangular wave generating circuit applied to the analog dither technology is provided with a voltage division module to provide two different reference voltages through resistance voltage division, a comparison control module and a charge-discharge module, wherein the comparison control module selects the two reference voltages in turn to be compared with the charge-discharge voltage of the charge-discharge module, so that once the charge-discharge voltage reaches the compared reference voltage, a corresponding control signal is output to switch the charge-discharge direction of the charge-discharge module, an initial voltage with a triangular waveform is formed, and the initial voltage is processed through a processing output module, so that the triangular wave voltage with driving capability and adjustable precision is output. Compared with the traditional triangular wave generating circuit, the triangular wave generating circuit has the advantages of simple structure, high precision, small occupied chip area and low development cost.
Drawings
Fig. 1 is a block diagram of a preferred embodiment of a triangle wave generating circuit applied to analog jitter frequency technology according to the present invention.
Fig. 2 is a circuit diagram of a voltage division module, a comparison control module and a charge-discharge module in fig. 1 according to a preferred embodiment.
FIG. 3 is a circuit diagram of a preferred embodiment of the processing output module of FIG. 1.
Fig. 4 is a diagram illustrating voltage waveforms of a preferred embodiment of fig. 2.
Description of the main elements
Triangular wave generating circuit 100 applied to analog jitter frequency technology
Charging and discharging module 30
Power VCC
Resistors R1, R2, R3, R4, R5, R6,
R7、R8
Capacitors C1, C2, C3, C4 and C5
Nodes G1, G2, G3, G4, G5
Transmission gates TG1, TG2
Comparators A1, A2
Schmitt trigger T1
The following detailed description will further illustrate the invention in conjunction with the above-described figures.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1, a triangle wave generating circuit 100 for analog jitter frequency technique is provided. The triangular wave generating circuit 100 applied to the analog dither technique includes a voltage dividing module 10, a comparison control module 20, a charging/discharging module 30, and a processing output module 40. The comparison control module 20 is electrically connected between the voltage dividing module 10 and the charging and discharging module 30. The processing output module 40 is electrically connected to the charging and discharging module 30.
The voltage division module 10 divides a power supply through a resistor to obtain a first reference voltage and a second reference voltage. The comparison control module 20 is configured to control to select the first reference voltage or the second reference voltage to compare with the charge and discharge voltage generated by the charge and discharge module 30, and output a control signal according to a comparison result, and the charge and discharge module 30 is configured to periodically perform charging or discharging according to the control signal to output an initial voltage having a triangular waveform. The processing output module 40 is configured to process the initial voltage to obtain a triangular wave voltage with driving capability and adjustable precision.
Further, the comparison control module 20 controls to select the first reference voltage or the second reference voltage to be compared with the charge and discharge voltage generated by the charge and discharge module 30 according to the output control signal. In this way, two different reference voltages are provided by the resistor voltage division, and the comparison control module 20 selects the two reference voltages in turn to compare with the charging and discharging voltages generated by the charging and discharging module 30, so that once the charging and discharging voltages reach the compared reference voltages, corresponding control signals are output to switch the charging and discharging directions of the charging and discharging module 30, thereby forming an initial voltage with a triangular waveform, and the initial voltage is processed by the processing output module 40, thereby outputting a triangular waveform voltage with driving capability and adjustable precision, wherein the adjustable precision of the triangular waveform voltage includes a triangular fluctuation amplitude, a period and a central value.
Referring to fig. 2, in the present embodiment, the voltage dividing module 10 includes resistors R1-R4, capacitors C1-C2, and a power VCC. One end of the resistor R1 is electrically connected with the power supply VCC, and the other end of the resistor R1 is sequentially connected with the resistor R3, the resistor R4 and the resistor R2 in series and then is grounded. One end of the capacitor C1 is grounded, and the other end thereof is electrically connected to a node G1 between the resistor R1 and the resistor R3. One end of the capacitor C2 is grounded, and the other end thereof is electrically connected to a node G2 between the resistor R4 and the resistor R2. The voltage divider module 10 outputs a first reference voltage through the node G1. The voltage divider module 10 outputs a second reference voltage through the node G2. The first reference voltage and the second reference voltage are used for controlling the central value and the upper and lower fluctuation amplitudes of the initial voltage. Therefore, the resistors R1-R4 with different resistance values can be selected to adjust the magnitudes of the first reference voltage and the second reference voltage, and further adjust the central value and the amplitude of the fluctuation. The capacitor C1 and the capacitor C2 are used for stabilizing the first reference voltage and the second reference voltage.
In this embodiment, the comparison control module 20 includes transmission gates TG1-TG2, a comparator a1, and a schmitt trigger T1. An input terminal of the transmission gate TG1 is electrically connected to the node G1, and an output terminal of the transmission gate TG1 is electrically connected to an inverting input terminal of the comparator a 1. An input terminal of the transmission gate TG2 is connected to the node G2, and an output terminal of the transmission gate TG2 is electrically connected with an inverting input terminal of the comparator A1. The non-inverting input terminal of the comparator a1 is electrically connected to the charge and discharge module 30. The output end of the comparator A1 is electrically connected with the input end of the Schmitt trigger T1. The output end of the schmitt trigger T1 is electrically connected to the control ends of the transmission gate TG1 and the transmission gate TG 2. The output end of the schmitt trigger T1 is also electrically connected to the charge and discharge module 30. In this embodiment, the input and output of the schmitt trigger T1 are of the inverted type. The schmitt trigger T1 is configured to, after performing anti-interference processing on the comparison result of the comparator a1, control the transmission gate TG1 and the transmission gate TG2 to turn on and off in turn, so as to control the first reference voltage and the second reference voltage to be selected in turn for the reference voltage to be compared, further turn over the comparator a1 in turn, output different comparison results, and act on the charge and discharge module 30 to enable the charge and discharge module 30 to perform charging or discharging in turn, thereby forming an initial voltage v3 having a triangular waveform.
In the present embodiment, the charge/discharge module 30 includes a resistor R5 and a capacitor C3. One end of the capacitor C3 is grounded, the other end of the capacitor C3 is electrically connected to the non-inverting input terminal of the comparator a1, and the other end of the capacitor C3 is further connected to the output terminal of the schmitt trigger T1 through the resistor R5. The node G3 between the resistor R5 and the capacitor C3 serves as an output terminal of the charging and discharging module 30 and is electrically connected to the processing output module 40. By selecting the resistor R5 with different resistance values and the capacitor C3 with different capacitance values, the period of the initial voltage v3 generated by the charge/discharge module 30 can be adjusted correspondingly.
Referring to fig. 4, the specific principle of the present embodiment is as follows: after the power source VCC is divided by resistors R1-R4, the first reference voltage v1 ═ u1 × R2/(R1+ R2+ R3+ R4) and the second reference voltage v2 ═ u1 (R2+ R3+ R4)/(R1+ R2+ R3+ R4) are formed, where u1 is a voltage provided by the power source VCC, and R1-R4 are resistance values of resistors R1-R4, respectively. The amplitude Δ v-u 1 r3/(r1+ r2+ r3+ r4) or Δ v-u 1 r4/(r1+ r2+ r3+ r4) of the initial voltage v3, wherein r 3-r 4. The central value VM1 of the initial voltage v3 is u1 (r3+ r4)/(r1+ r2+ r3+ r 4). Referring to fig. 3, in a T1 period, when the initial voltage v3 is greater than the voltage v4 at the inverting input terminal of the comparator a1, i.e. v3 > v4, the comparator a1 outputs a high level, the transmission gate TG1 is closed, the transmission gate TG2 is turned on, the voltage v4 at the inverting input terminal of the comparator a1 becomes the first reference voltage v1, during which a low level continues to be output after inverting through the schmitt trigger T1, the low level discharges the capacitor C3 through the resistor R5, the initial voltage v3 drops, and at a moment after dropping to the first reference voltage v1, the comparator a1 flips, the comparator a1 outputs a low level, the transmission gate TG 7 is turned on, the transmission gate 3687458 is closed, the voltage v1 at the inverting input terminal of the comparator a1 becomes the second reference voltage v1, and at this moment, the inverse input terminal of the schmitt trigger T1 continues to the high level TG 36 1 2, the high level will charge the capacitor C3 through the resistor R5, the initial voltage v3 rises, and at a moment after rising to the second reference voltage v2, the comparator a1 flips again, the comparator a1 outputs high level, the transmission gate TG1 is closed, the transmission gate TG2 is turned on, the voltage v4 at the inverting input terminal of the comparator a1 becomes the first reference voltage v1, and the steps are repeated, so that the initial voltage v3 with a triangular waveform is formed. In the present embodiment, T1 ═ C3 ═ r5/v4, and T2 ═ C3 ═ r5/(u1-v4), where C3 is the capacitance value of capacitor C3.
Further, referring to FIG. 3, the processing output module 40 includes a comparator A2, resistors R6-R8, and capacitors C4-C5. The non-inverting input terminal of the comparator A2 is electrically connected to the node G3 between the resistor R5 and the capacitor C3. The inverting input terminal of the comparator A2 is electrically connected with the output terminal of the comparator A2. The output terminal of the comparator a2 is electrically connected to the output terminal of the triangular wave generating circuit 100 applied to the analog dither technique through the resistor R6. One end of the resistor R7 is electrically connected to the power VCC, and a node G4 at the other end of the resistor R7 is connected in series with the resistor R8 and then grounded. One end of the capacitor C4 is electrically connected to the power VCC, and a node G5 at the other end of the capacitor C4 is connected in series with the capacitor C5 and then grounded. The node G4 is electrically connected with the node G5. The node G5 is electrically connected with the node G3. The comparator a2 is used as a follower to convert the initial voltage v3 output by the charge and discharge module 30 into a triangular wave voltage vref with driving capability, and the resistor R6 is used to charge or discharge the post-stage capacitor C4 and the capacitor C5, so as to reduce the amplitude of the triangular wave. The resistor R7, the resistor R8, the capacitor C4 and the capacitor C5 are further used for forming a center point bias unit, and the center point bias unit is used for keeping the finally output triangular wave voltage vref consistent with the center point of the initial voltage v3, namely VM-VM 1.
The triangular wave generating circuit 100 applied to the analog dither technology is provided with the voltage dividing module 10 to provide two different reference voltages through resistance voltage division, and further provided with the comparison control module 20 and the charge and discharge module 30 to select the two reference voltages in turn through the comparison control module 20 to compare with the charge and discharge voltages generated by the charge and discharge module 30, so that once the charge and discharge voltages reach the compared reference voltages, corresponding control signals are output to switch the charge and discharge directions of the charge and discharge module 30, an initial voltage with a triangular waveform is formed, and the initial voltage is processed through the processing output module 40, so that a triangular wave signal with driving capability and adjustable precision is obtained. Compared with the traditional triangular wave generating circuit, the triangular wave generating circuit has the advantages of simple structure, high precision, small occupied chip area and low development cost.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (7)
1. A triangular wave generating circuit applied to an analog jitter frequency technology is characterized by comprising a voltage division module, a comparison control module, a charge-discharge module and a processing output module, wherein the comparison control module is electrically connected between the voltage division module and the charge-discharge module, the processing output module is electrically connected with the charge-discharge module, the voltage division module divides a power supply through a resistor to obtain a first reference voltage and a second reference voltage, the comparison control module is used for controlling and selecting the first reference voltage or the second reference voltage to be compared with the charge-discharge voltage generated by the charge-discharge module and outputting a control signal according to a comparison result, the charge-discharge module is used for periodically charging and discharging according to the control signal to output an initial voltage with a triangular waveform, and the processing output module is used for processing the initial voltage to obtain triangular wave voltage with driving capability and adjustable precision.
2. The triangle wave generating circuit applied to analog dither technique according to claim 1, wherein the comparing control module controls to select the first reference voltage or the second reference voltage to compare with the charging and discharging voltage generated by the charging and discharging module according to the outputted control signal.
3. The triangular wave generating circuit applied to the analog dither technique of claim 1, wherein the voltage dividing module comprises a resistor (R1), a resistor (R2), a resistor (R3), a resistor (R4), a capacitor (C1), a capacitor (C2) and a power supply (VCC), one end of the resistor (R1) is electrically connected to the power supply (VCC), the other end of the resistor (R1) is sequentially connected in series with the resistor (R3), the resistor (R4) and the resistor (R2) to ground, one end of the capacitor (C1) is connected to ground, the other end of the capacitor is electrically connected to a node (G1) between the resistor (R1) and the resistor (R3), one end of the capacitor (C2) is connected to ground, the other end of the capacitor (R2) is electrically connected to a node (G2) between the resistor (R4) and the resistor (R2), and the voltage dividing module outputs a first reference voltage through the node (G1), the voltage divider module outputs a second reference voltage through the node (G2).
4. The triangle wave generating circuit applied to analog frequency jitter technique of claim 3, wherein said comparison control module comprises a transmission gate (TG1), a transmission gate (TG2), a comparator (A1) and a Schmitt trigger (T1), an input terminal of said transmission gate (TG1) is electrically connected to said node (G1), an output terminal of said transmission gate (TG1) is electrically connected to an inverting input terminal of said comparator (A1), an input terminal of said transmission gate (TG2) is connected to said node (G2), an output terminal of said transmission gate (TG2) is electrically connected to an inverting input terminal of said comparator (A1), a non-inverting input terminal of said comparator (A1) is electrically connected to said charge-discharge module, an output terminal of said comparator (A1) is electrically connected to an input terminal of said Schmitt trigger (T1), an output terminal of said Schmitt trigger (T1) is electrically connected to said transmission gate (TG 29) and a control terminal of said transmission gate (TG2), the output end of the Schmitt trigger (T1) is also electrically connected with the charging and discharging module, and the input end and the output end of the Schmitt trigger (T1) are of a reverse type.
5. The triangle wave generating circuit applied to analog dither technology of claim 4, wherein said charge-discharge module includes a resistor (R5) and a capacitor (C3), one end of said capacitor (C3) is grounded, the other end of said capacitor (C3) is electrically connected to the non-inverting input terminal of said comparator (a1), the other end of said capacitor (C3) is further connected to the output terminal of said schmitt trigger (T1) through said resistor (R5), and a node (G3) between said resistor (R5) and said capacitor (C3) is used as the output terminal of said charge-discharge module and is electrically connected to said processing output module.
6. The triangle wave generating circuit applied to analog dither technique of claim 5, wherein said processing output module comprises a comparator (A2) and a resistor (R6), a non-inverting input terminal of said comparator (A2) is electrically connected to a node (G3) between said resistor (R5) and said capacitor (C3), an inverting input terminal of said comparator (A2) is electrically connected to an output terminal of said comparator (A2), and an output terminal of said comparator (A2) is electrically connected to an output terminal of said triangle wave generating circuit applied to analog dither technique through said resistor (R6).
7. The triangle wave generating circuit applied to analog dither technology of claim 6, wherein said processing output module further comprises a resistor (R7), a resistor (R8), a capacitor (C4) and a capacitor (C5), one end of said resistor (R7) is electrically connected to said power supply (VCC), a node (G4) at the other end of said resistor (R7) is connected in series with said resistor (R8) and then grounded, one end of said capacitor (C4) is electrically connected to said power supply (VCC), a node (G5) at the other end of said capacitor (C4) is connected in series with said capacitor (C5) and then grounded, and said node (G4) is electrically connected to said node (G5). The node (G5) is electrically connected to the output end of the triangular wave generating circuit applied to the analog jitter frequency technology.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110635605.8A CN113395059A (en) | 2021-06-08 | 2021-06-08 | Triangular wave generating circuit applied to analog jitter frequency technology |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110635605.8A CN113395059A (en) | 2021-06-08 | 2021-06-08 | Triangular wave generating circuit applied to analog jitter frequency technology |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113395059A true CN113395059A (en) | 2021-09-14 |
Family
ID=77618663
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110635605.8A Pending CN113395059A (en) | 2021-06-08 | 2021-06-08 | Triangular wave generating circuit applied to analog jitter frequency technology |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113395059A (en) |
-
2021
- 2021-06-08 CN CN202110635605.8A patent/CN113395059A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8350631B1 (en) | Relaxation oscillator with low power consumption | |
| CN107241098B (en) | Offset calibration circuit of comparator in asynchronous successive approximation type analog-to-digital converter | |
| US8884676B2 (en) | Clock generator with duty cycle control and method | |
| CN112234957B (en) | Analog oscillator circuit with negative feedback regulation function | |
| CN111697947B (en) | High-precision wide-range relaxation oscillator insensitive to temperature | |
| CN110518896B (en) | Clock generating circuit and chip for providing arbitrary frequency and duty ratio | |
| CN114336274B (en) | Laser driving circuit and laser | |
| JP3761858B2 (en) | Clock signal generation circuit | |
| EP2584719B1 (en) | Control circuit for reducing electromagnetic interference | |
| US7102405B2 (en) | Pulse-width modulation circuit and switching amplifier using the same | |
| CN112910446A (en) | Oscillator | |
| JPH10224186A (en) | Voltage-controlled oscillator | |
| US9973081B1 (en) | Low-power low-duty-cycle switched-capacitor voltage divider | |
| CN111900960B (en) | Phase interpolation system | |
| CN215581086U (en) | Triangular wave generating circuit applied to analog jitter frequency technology | |
| CN109302166A (en) | Pulse width modulation circuit and device | |
| CN210405226U (en) | RC oscillating circuit | |
| CN113395059A (en) | Triangular wave generating circuit applied to analog jitter frequency technology | |
| US7898311B2 (en) | Phase shifting circuit which produces phase shift signal regardless of frequency of input signal | |
| CN216794859U (en) | Charging and discharging circuit | |
| US9705480B2 (en) | Circuit and method for generating an output signal having a variable pulse duty factor | |
| CN114640324A (en) | Low-power-consumption periodic pulse generation circuit | |
| CN204145433U (en) | RC filter digital tuning circuitry | |
| CN110739937A (en) | switch type square wave generator using parallel reference voltage source | |
| JP3345209B2 (en) | Multiplier circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |