Crystal oscillator driving system capable of rapidly starting oscillation and method thereof

Abstract

The invention discloses a crystal oscillator driving system capable of rapidly starting oscillation, which comprises an OSC circuit connected to a crystal and used for charging the crystal, a crystal oscillator connected to the crystal and used for driving the crystal to generate a sine clock signal, and an energy injection control circuit connected to the OSC circuit, the detection circuit is connected with the crystal oscillator and the energy injection control circuit; the energy injection control circuit sends a control signal to the OSC circuit to control the output frequency of the OSC circuit, so that the output frequency of the OSC circuit is sequentially increased from low to high; the detection circuit receives the detection signal sent by the energy injection control circuit so as to detect whether the crystal oscillator outputs a clock signal. The output frequency of the OSC circuit is sequentially and gradually increased through the energy injection control circuit, so that the requirement that the crystal is not subjected to PVT conditions, and rapid oscillation starting is realized under different driving currents and different crystal types when energy is injected in advance can be met.

Description

Technical Field

[0001] The invention relates to the field of CMOS integrated circuit design, and in particular to a fast-starting crystal oscillator driving system and a method thereof. Background Art

[0002] Since the advent of crystal drivers in the 1920s, their theoretical research and manufacturing levels have developed rapidly, and various performance indicators have been significantly improved. As a clock frequency source, compared with other types of oscillators, crystal oscillators are widely used in military and civilian consumer electronics fields with their excellent Q value, frequency accuracy, stability, etc. As a high-quality clock source, the crystal oscillator clock is a necessary reference clock for generating high-quality high-frequency clocks. Its response speed is directly related to the response time of the subsequent frequency multiplication circuit (such as the phase-locked loop PLL), thereby affecting the response speed of the system. The research and development of fast-starting crystal oscillator circuits is crucial.

[0003] Crystals are high-Q components that need to accumulate energy to start oscillating. Conventional crystal drive circuits, such as 25MHz crystal oscillators, sometimes take 1 to 5ms or even longer to start oscillating under different PVT (Process, Voltage, Temperature) conditions, different drive currents, and different crystal types. In order to achieve fast oscillation, the existing technology often uses OSC (Oscillator) to inject energy into the crystal in advance.

[0004] However, to inject energy in advance, the accuracy of the OSC itself must be within ±1% to achieve fast oscillation without being restricted by PVT conditions, different drive currents, and different crystal types. Therefore, the existing technology is more dependent on the accuracy of the OSC itself. The better the energy injection effect, the faster the crystal oscillator circuit starts. Summary of the invention

[0005] The main purpose of the present invention is to provide a fast-starting crystal oscillator driving system and method thereof, aiming to reduce the crystal starting time.

[0006] To achieve the above-mentioned object, the present invention provides a fast-starting crystal oscillator driving system, comprising an OSC circuit connected to a crystal and charging it, and a crystal oscillator connected to the crystal and driving the crystal to generate a sinusoidal clock signal, and also comprising an energy injection control circuit connected to the OSC circuit, and a detection circuit connected to the crystal oscillator and the energy injection control circuit; The energy injection control circuit sends a control signal to the OSC circuit to control the output frequency of the OSC circuit, so that the output frequency of the OSC circuit increases from low to high; The OSC circuit is connected to the crystal via a switch tube, the energy injection control circuit is connected to the switch tube, and outputs a charging signal to the switch tube to control the switch tube to open / close, so that the OSC circuit disconnects / connects the crystal; The detection circuit receives a detection signal sent by the energy injection control circuit to detect whether the crystal oscillator has a clock signal output; when the crystal oscillator outputs a valid clock signal, the detection circuit sends an indication signal to the energy injection control circuit and the OSC circuit respectively to shut down the energy injection control circuit and the OSC circuit.

[0007] Preferably, the detection circuit includes a clock buffer and a counter, the clock buffer is connected to the crystal oscillator to drive the sinusoidal clock signal output by the crystal oscillator into a square wave clock signal; the counter counts the square wave clock signal, and when the count reaches a preset period, it is determined that the crystal has started to oscillate, and an indication signal is sent to turn off the energy injection control circuit and the OSC circuit; when the count does not reach the preset period, it is determined that the crystal has not started to oscillate, and an indication signal is sent to the energy injection control circuit to readjust the output frequency of the OSC circuit.

[0008] Preferably, the detection circuit further comprises an AND gate subcircuit, two input ends of the AND gate subcircuit are respectively connected to the output ends of the clock buffer and the counter, and the output end is used to output a stable clock signal.

[0009] Preferably, the control signal has 16 bits, and its value increases from low to high.

[0010] Preferably, the control signal has 32 bits, and its value increases from low to high.

[0011] The present invention also provides a crystal oscillator driving method for rapid oscillation start-up, comprising the following steps: S1, generate a control signal for adjusting the frequency of the OSC circuit: In the initial state, the output frequency of the OSC circuit is adjusted to the lowest frequency within its error output range by outputting a control signal through the energy injection control circuit; in subsequent cycle steps, the output frequency of the OSC circuit is sequentially increased by the control signal; S2. Charge the crystal and drive the crystal to generate a clock signal output: Generate a charging signal through an energy injection control circuit, connect the OSC circuit and the crystal, and charge the crystal through the OSC circuit; when a preset cycle is completed, turn off the charging; S3, generating a detection signal through the energy injection control circuit to detect whether there is a clock signal output: If a valid clock output is detected, it means that the crystal has started to oscillate, and the energy injection control circuit and the OSC circuit are turned off; If no valid clock output is detected, the process returns to step S1, the OSC circuit output frequency is increased in sequence, and steps S1-S3 are repeated until a valid clock output is detected.

[0012] Preferably, the control signal has 16 bits, and its value increases from low to high.

[0013] Preferably, the control signal has 32 bits, and its value increases from low to high.

[0014] Preferably, the clock detection circuit includes a clock buffer and a counter. The clock buffer drives the sine wave clock signal received from the crystal oscillation circuit into a square wave clock signal. The counter counts the square wave clock signal.

[0015] Preferably, step S3 also includes: timing the clock signal through the counter, and when the count reaches a preset period, judging that the current clock signal is a valid clock signal and the crystal has started to oscillate, and sending an indication signal through the counter to turn off the energy injection control circuit and the OSC circuit; when the count does not reach the preset period, judging that the crystal has not started to oscillate, and sending an indication signal to the energy injection control circuit to readjust the output frequency of the OSC circuit.

[0016] The technical solution of the present invention controls the output frequency of the OSC circuit through an energy injection control circuit, starting from the lowest frequency within the error range, and gradually increases the output frequency of the OSC circuit until the clock output is detected; the output frequency of the OSC circuit is gradually increased through the energy injection control circuit, which can meet the requirements of fast oscillation of the crystal under PVT conditions, different driving currents and different crystal types when energy is injected in advance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of the circuit principle of a crystal oscillator driving system for rapid oscillation start-up according to an embodiment of the present invention; Figure 2 Schematic diagram of the logical relationship among the control signal, OSC output frequency, charging signal, detection signal and indication signal in an embodiment of the present invention; Figure 3 A schematic diagram of the process flow of a crystal oscillator driving method for rapid oscillation start-up according to an embodiment of the present invention; Figure 4 It is a schematic diagram of the simulation of the oscillation time of the oscillation circuit in the prior art; Figure 5 The figure is a schematic diagram of the simulation of the start-up time of the crystal oscillator driving system with fast start-up according to the embodiment of the present invention.

[0018] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0019] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0020] The present invention is further described below in conjunction with the accompanying drawings.

[0021] A fast-starting crystal oscillator drive system, such as Figure 1 As shown, including: an OSC circuit and a crystal oscillator connected to the crystal, an energy injection control circuit connected to the OSC circuit, and a detection circuit connected to the crystal oscillator and the energy injection control circuit; The energy injection control circuit is connected to the OSC circuit and sends a control signal FT to the OSC circuit to control the output frequency CK_OSC of the OSC circuit so that the output frequency CK_OSC increases from low to high. The OSC circuit is connected to the crystal through the switch tube. When the energy injection control circuit outputs a charging signal to the switch tube to control its closing, the OSC circuit charges the crystal. When the energy injection control circuit outputs a charging signal EN_POWER to disconnect the switch tube, the OSC circuit disconnects from the crystal. A crystal oscillator is connected to the crystal and is used to drive the crystal to generate a sinusoidal clock signal; The detection circuit is connected to the crystal oscillator. When the detection circuit receives the detection signal EN_CHECK sent by the energy injection control circuit, it detects whether the crystal oscillator has a clock signal output; when the crystal oscillator outputs a valid clock signal, the detection circuit feeds back an indication signal CK_Cheek to turn off the energy injection control circuit and the OSC circuit.

[0022] The detection circuit includes a clock buffer and a counter. The clock buffer is connected to the crystal oscillator and is used to drive the sinusoidal clock signal output by the crystal oscillator into a square wave clock signal. The counter counts the square wave clock signal. When the count reaches a preset period, it is determined that the crystal has started to oscillate, and an indication signal CK_Cheek is sent to turn off the energy injection control circuit and the OSC circuit. When the count does not reach the preset period, it is determined that the crystal has not started to oscillate, and an indication signal CK_Cheek is sent to the energy injection control circuit to readjust the output frequency CK_OSC of the OSC circuit. Specifically, the counter can be set to different counting periods, and the longer the counting period, the higher the clock stability or the more accurate the clock validity. For example, the counter can be set to count 128 / 256 / 512 periods of the square wave clock signal. The detection circuit also includes an AND gate subcircuit, and the two input ends of the AND gate subcircuit are respectively connected to the output ends of the clock buffer and the counter, and the output end is used to output a stable clock signal.

[0023] In a specific embodiment, the OSC circuit is used to generate a clock with the same frequency as the crystal, and can support any common frequency accuracy on the market, such as within ±10%, preferably ±3%, ±5%. The output frequency CK_OSC of the OSC circuit adjusted by the control signal FT of the energy injection control circuit is used to inject energy into the crystal.

[0024] The energy injection control circuit is implemented through digital logic to generate a control signal FT for adjusting the output frequency CK_OSC of the OSC circuit, generate an energy charging signal EN_POWER to turn on / off the switch between the OSC circuit and the crystal, and generate a detection signal EN_CHECK to the detection circuit to detect whether the crystal is oscillating.

[0025] Specifically, the number of bits of the control signal FT is 32 bits, and its value increases from low to high, that is, the control signal FT[4:0]=5b´00000→5b´11111.

[0026] The relationship between the control signal FT, the charging signal EN_POWER and the detection signal EN_CHECK satisfies the following: Figure 2 The logical relationship shown is: In the initial state, the energy injection control circuit outputs an initial control signal FT to the OSC circuit to control the output frequency CK_OSC of the OSC circuit; at the same time, the energy injection control circuit sends a charging signal EN_POWER to the switch tube to connect the OSC circuit and the crystal, so that the OSC circuit charges the crystal; after charging 128 cycles (or 256 cycles or 512 cycles, etc.) of the output frequency CK_OSC of the OSC circuit, the energy injection control circuit turns off the charging signal EN_POWER, and at the same time sends a detection signal EN_CHECK to the clock buffer and counter in the detection circuit to detect whether the charging completes the oscillation of the crystal; the cycle of the detection signal EN_CHECK can be set to 128 cycles, 256 cycles, or 512 cycles of the clock signal, etc. When the counter counts the preset cycle, it is judged that the crystal oscillator outputs a valid clock signal and the crystal has started to oscillate, and the indication signal CK_Cheek outputs a high level; when the counter does not count the preset cycle, it is judged that the crystal has not started to oscillate, and the indication signal CK_Cheek outputs a low level.

[0027] If the crystal does not oscillate, the energy injection control circuit outputs a control signal FT to increase the frequency of the OSC circuit, and cycles through the charging and detection process until it is detected that the crystal has oscillated. At this time, the indication signal CK_Cheek outputs a high level to the energy injection control circuit and the OSC circuit to shut down the energy injection control circuit and the OSC circuit.

[0028] The embodiment of the present invention also provides a crystal oscillator driving method for rapid oscillation start-up. Figure 3 As shown, the following steps are included: S1, generate a control signal FT for adjusting the frequency of the OSC circuit: In the initial state, the output frequency CK_OSC of the OSC circuit is adjusted to the lowest frequency within its output range through the energy injection control circuit; In subsequent cycle steps, the output frequency CK_OSC of the OSC circuit is increased in sequence, specifically: a control signal FT is sent through the energy injection control circuit to control the output frequency CK_OSC of the OSC circuit to increase the output frequency CK_OSC of the OSC circuit in sequence from the worst frequency within the error range, and the crystal is charged with energy through the increased output frequency CK_OSC in sequence until the crystal successfully starts to oscillate to output a clock signal.

[0029] Specifically, the output range of the OSC circuit refers to its own frequency deviation under different working conditions plus the adjustment range of the control signal.

[0030] In order to meet the requirement that the output of the OSC circuit is adjusted from the lowest frequency to the highest frequency in sequence, the embodiment of the present invention sets the number of bits of the control signal FT of the energy injection control circuit to 16 bits or 32 bits, that is, the control signal FT[3:0]=4b´0000→4b´1111, or FT[4:0]=5b´00000→5b´11111. Meanwhile, in other embodiments, the designer can also design other numbers of bits of the control signal FT, such as 8 bits, 64 bits, etc., according to the accuracy of the OSC circuit output frequency CK_OSC.

[0031] In a specific embodiment, the OSC circuit generates a clock with the same frequency as the crystal, and after calibration, the output frequency accuracy is between ±5%, and supports the actual output frequency to be adjusted within the range of -5% to +5%. The adjustable accuracy range of the OSC circuit is 10%. If the number of bits of the control signal FT is set to 16 bits, in order to enable the energy injection control circuit to proportionally control the OSC circuit to increase the output frequency CK_OSC, the value of the control signal FT[3:0] is increased by 1, and FT[3:0]=4b´0000 becomes FT[3:0]=4b´0001, so that the output frequency CK_OSC can be adjusted to +0.625% each time, that is, 0.625% is increased based on the output frequency CK_OSC of the previous round of the OSC circuit; if the number of bits of the control signal FT is set to 32 bits, the value of the control signal FT[4:0 ] plus 1, from FT[4:0]=5b´00000 to FT[4:0]=5b´00001, which can make the output frequency adjusted each time +0.3125%, that is, increase the output frequency CK_OSC of the previous OSC circuit by 0.3125%; in this way, the output frequency CK_OSC of the OSC circuit is gradually increased through the energy injection control circuit, and the frequency increase each time does not exceed 1%, so it can meet the requirements of fast oscillation of the crystal under PVT conditions, different drive currents and different crystal types when energy is injected in advance.

[0032] At the same time, if the accuracy of the output frequency CK_OSC of the OSC circuit is between ±8% and supports the adjustment of the actual output frequency within the range of -8% to +8%, the adjustable accuracy range of the OSC circuit is 16%. In order to enable the energy injection control circuit to increase the output frequency CK_OSC of the OSC circuit in proportion, the number of bits of the control signal FT is set to 16 bits, and the output frequency is adjusted by +1% each time; the number of bits of the control signal FT is set to 32 bits, and the output frequency is adjusted by +0.5% each time.

[0033] At the same time, if the accuracy of the output frequency CK_OSC of the OSC circuit is between ±3% and supports the adjustment of the actual output frequency within the range of -3% to +3%, the adjustment accuracy of the OSC circuit is 6%. In order to make the control circuit proportionally increase the output frequency CK_OSC of the OSC circuit, if the number of bits of the control signal FT is set to 16 bits, the output frequency is adjusted by +0.375% each time; if the number of bits of the control signal FT is set to 32 bits, the output frequency is adjusted by +0.1875% each time; or if the number of bits of the control signal FT is set to 8 bits, the output frequency is adjusted by +0.75% each time, and the control signal FT[2:0]=3b´000→ 3b´111.

[0034] Since the accuracy of the output frequency CK_OSC of a common OSC circuit is ±5%, the preferred control signal FT bit number of the embodiment of the present invention is set to 32 bits, that is, FT[4:0]=5b´00000→ 5b´11111. In a specific embodiment, the number of bits of the control signal FT is set to 32 bits, which also supports the OSC circuits on the market with an output frequency accuracy within ±10%. If the output frequency is in other accuracy ranges, the output frequency can be adjusted by setting the control signal FT with other bits. In actual situations, designers can design the number of bits of the control signal FT according to the specific output frequency accuracy range of the OSC circuit.

[0035] S2, charge the crystal and drive the crystal to generate clock output: The energy injection control circuit generates a charging signal EN_POWER, connects the OSC circuit and the crystal, and generates an oscillation signal to start the crystal through the OSC circuit to charge the crystal; when the preset cycle is fully completed, the charging is turned off.

[0036] In some embodiments, the charging signal EN_POWER can be set to charge the crystal for 128, 256, 512 or other cycles before disconnecting the charging. Different cycles can be set according to actual circuit conditions. Specifically, the charging cycle is 128, 256 or 512 cycles of the OSC circuit output frequency.

[0037] In some embodiments, a crystal is driven by a crystal oscillator circuit to generate a sinusoidal clock, and the structure of the crystal oscillator circuit can be implemented by a conventional structure, such as an inverter architecture, a Pierce oscillator, and the like.

[0038] S3, the energy injection control circuit generates a detection signal EN_CHECK to detect whether there is a clock output: If the clock output is detected, it means that the crystal has started to oscillate, and the energy injection control circuit and OSC circuit are turned off; If the clock output is not detected, the process returns to step S1, the output frequency of the OSC circuit is increased in sequence, and steps S1-S3 are repeated until the clock output is detected.

[0039] In some embodiments, after the charging is turned off, the energy injection control circuit outputs a detection signal EN_CHECK to detect the output clock. If the clock output is still not detected after a preset period, it means that the crystal has not started to oscillate, then return to step S1, increase the output frequency of the OSC circuit, charge the crystal again, and drive the crystal to generate a clock output. When the charging is completed, it is detected whether there is a clock output at the same time until the clock output is detected.

[0040] In a specific embodiment, the system detects whether the crystal outputs a valid clock through a clock detection circuit, and outputs an indication signal CK_Cheek to the energy injection control circuit. When the indication signal CK_Cheek indicates that there is no valid clock, the energy injection control circuit sends a control signal FT to increase the output frequency CK_OSC of the OSC circuit, and recharges the crystal to detect whether a valid clock is output; when the indication signal CK_Cheek indicates that a valid clock is output, the energy injection control circuit and the OSC circuit are turned off, and at the same time, the energy injection control circuit disconnects the OSC circuit and the crystal, so that the clock detection circuit remains normally open.

[0041] Specifically, the clock detection circuit includes a clock buffer and a counter. The clock buffer drives the sinusoidal clock signal received from the crystal oscillator circuit into a square wave clock signal. The counter counts the square wave clock signal. The counting period of the counter is the detection period. The counter is set to 128 or 256 or 512 or other periods of the clock signal, and can be flexibly set according to the reliability of the detection.

[0042] The detection cycle is 128, 256 or 512 cycles of the clock signal. When the counter is full, the output indication signal CK_Cheek is high level "1" and the crystal oscillator clock is output at the same time; if the counter is not full, the indication signal CK_Cheek is low level "0" and the crystal oscillator clock is low level "0".

[0043] Taking a 25MHz crystal and an OSC circuit output frequency accuracy of ±5% as an example, the working process of the embodiment of the present invention is described in detail as follows: In the initial state, the crystal is not oscillating, and the clock output CK_OUT is 0. At this time, the clock detection circuit outputs the indication signal CK_Cheek as a low level; the OSC circuit receives the control signal FT[4:0]=5b´00000 sent by the energy injection control circuit, controls the OSC circuit output frequency CK_OSC to -5%, and the energy injection control circuit outputs the charging signal EN_POWER=“1” to charge the crystal; After charging for 128 cycles of the OSC circuit output frequency, the charging signal EN_POWER is set to "0" to turn off charging. At this time, the detection signal EN_CHECK is set to "1" to detect the output clock. If the indication signal CK_Cheek remains at a low level "0" after 256 cycles of the square wave clock signal, it means that the clock detection circuit has not detected the crystal oscillator starting.

[0044] The clock detection circuit feeds the indication signal CK_Cheek back to the energy injection control circuit. The energy injection control circuit controls the OSC circuit to adjust its output frequency by 0.3125% by adding 1 to the control signal FT[4:0] to 5b´00001. At the same time, the energy injection control circuit outputs the charging signal EN_POWER from "0" to "1", charging the crystal again, and repeating the previous charging and detection until the indication signal CK_Cheek detects a stable crystal oscillator clock and sends a "1" logic. At this time, the indication signal CK_Cheek outputs a high level "1" to the OSC circuit and the energy injection control circuit, so that: the OSC circuit turns off the output, that is, CK_OSC outputs 0; the energy injection control circuit outputs a low level charging signal EN_POWER to disconnect the crystal and the OSC circuit, that is, to turn off the crystal charging. At the same time, the energy injection control circuit outputs a high level detection signal EN_CHECK to keep the clock detection circuit normally open, and the clock output CK_OUT sends a stable 24MHz crystal oscillator clock.

[0045] In other embodiments, the crystal oscillator driving system of the present invention may use other types of crystals commonly available in the market.

[0046] According to the simulation results, when the crystal oscillator drive system of the present invention is not used to start the crystal, it usually takes 1 to 5 mS to start the crystal. Figure 4 As shown in the figure, without the introduction of fast start-up, it takes nearly 1.6mS to start oscillation; Figure 5 As shown, under the same conditions, the fast-starting crystal oscillator driving system of the present invention can start oscillating within 0.2 mS, which greatly reduces the crystal start-up time.

[0047] It should be understood that the above are only preferred embodiments of the present invention, and the patent scope of the present invention cannot be limited thereto. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A fast-starting crystal oscillator driving system, comprising an OSC circuit connected to a crystal and charging it, and a crystal oscillator connected to the crystal and driving the crystal to generate a sinusoidal clock signal, characterized in that: Also includes an energy injection control circuit connected to the OSC circuit, and a detection circuit connected to the crystal oscillator and the energy injection control circuit; The energy injection control circuit sends a control signal to the OSC circuit to control the output frequency of the OSC circuit, so that the output frequency of the OSC circuit increases from low to high; The OSC circuit is connected to the crystal via a switch tube, the energy injection control circuit is connected to the switch tube, and outputs a charging signal to the switch tube to control the switch tube to open / close, so that the OSC circuit disconnects / connects the crystal; The detection circuit receives a detection signal sent by the energy injection control circuit to detect whether the crystal oscillator has a clock signal output; when the crystal oscillator outputs a valid clock signal, the detection circuit sends an indication signal to the energy injection control circuit and the OSC circuit respectively to shut down the energy injection control circuit and the OSC circuit.

2. The fast-starting crystal oscillator drive system according to claim 1, characterized in that: The detection circuit includes a clock buffer and a counter, wherein the clock buffer is connected to the crystal oscillator to drive the sinusoidal clock signal output by the crystal oscillator into a square wave clock signal; The counter counts the square wave clock signal, and when the count reaches a preset period, it is determined that the crystal has started to oscillate, and an indication signal is sent to turn off the energy injection control circuit and the OSC circuit; when the count does not reach the preset period, it is determined that the crystal has not started to oscillate, and an indication signal is sent to the energy injection control circuit to readjust the output frequency of the OSC circuit.

3. The fast-starting crystal oscillator drive system according to claim 2, characterized in that: The detection circuit also includes an AND gate subcircuit, two input ends of the AND gate subcircuit are respectively connected to the output end of the clock buffer and the counter, and the output end is used to output a stable clock signal.

4. The fast-starting crystal oscillator drive system according to claim 2, characterized in that: The number of bits of the control signal is 16 bits, and its value increases from low to high.

5. The fast-starting crystal oscillator drive system according to claim 2, characterized in that: The number of bits of the control signal is 32 bits, and its value increases from low to high.

6. A crystal oscillator driving method for rapid oscillation start-up, characterized in that: The following steps are involved: S1, generate a control signal for adjusting the frequency of the OSC circuit: In the initial state, the energy injection control circuit outputs a control signal to adjust the output frequency of the OSC circuit to the lowest frequency within its output range; in subsequent cycle steps, the output frequency of the OSC circuit is sequentially increased by the control signal; S2. Charge the crystal and drive the crystal to generate a clock signal output: Generate a charging signal through an energy injection control circuit, connect the OSC circuit and the crystal, and charge the crystal through the OSC circuit; when a preset cycle is completed, turn off the charging; S3, generating a detection signal through the energy injection control circuit to detect whether there is a clock signal output: If a valid clock output is detected, it means that the crystal has started to oscillate, and the energy injection control circuit and the OSC circuit are turned off; If no valid clock output is detected, the process returns to step S1, the OSC circuit output frequency is increased in sequence, and steps S1-S3 are repeated until a valid clock output is detected.

7. The crystal oscillator driving method for rapid oscillation start-up according to claim 6, characterized in that: The number of bits of the control signal is 16 bits, and its value increases from low to high.

8. The crystal oscillator driving method for rapid oscillation start-up according to claim 6, characterized in that: The number of bits of the control signal is 32 bits, and its value increases from low to high.

9. The crystal oscillator driving method for rapid oscillation start-up according to claim 6, characterized in that: The clock detection circuit includes a clock buffer and a counter. The clock buffer drives the sine wave clock signal received from the crystal oscillation circuit into a square wave clock signal, and the counter counts the square wave clock signal.

10. The crystal oscillator driving method for rapid oscillation start-up according to claim 9, characterized in that: The step S3 further comprises: The clock signal is timed by the counter, and when the count reaches a preset period, it is determined that the current clock signal is a valid clock signal and the crystal has started to oscillate, and an indication signal is sent through the counter to turn off the energy injection control circuit and the OSC circuit; when the count does not reach the preset period, it is determined that the crystal has not started to oscillate, and an indication signal is sent to the energy injection control circuit to readjust the output frequency of the OSC circuit.

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