WO2019183943A1

WO2019183943A1 - Automatic amplitude control device and method

Info

Publication number: WO2019183943A1
Application number: PCT/CN2018/081402
Authority: WO
Inventors: 周涵超; 王明贵; 陈永权; 戴惜时; 秦鹏; 叶刘晓; 宋翔; 张�成; 何钰娟
Original assignee: 华为技术有限公司
Priority date: 2018-03-30
Filing date: 2018-03-30
Publication date: 2019-10-03
Also published as: CN111566937A

Abstract

Provided in an embodiment of the present invention are an automatic amplitude control device and method. The device comprises: an oscillator and a current source array, wherein one terminal of the current source array is coupled with a source terminal of a cross-coupling tube in the oscillator, and another terminal of the current source array is coupled with the ground. The device further comprises: a comparator that is used for comparing an amplitude detection signal of the oscillator to a reference voltage signal so as to obtain a comparison result; and a controller that is used for controlling, according to the comparison result, a current of the current source array coupled with the source terminal. In the embodiment of the present invention, the design is simple, the area expenses are low, and power consumption is low.

Description

Automatic amplitude control device and method

Technical field

The present application relates to the field of circuits, and in particular, to an automatic amplitude control apparatus and method.

Background technique

Under the current process conditions, the variation of the process voltage temperature (PVT) has a great influence on the amplitude of the Voltage Controlled Oscillator (VCO). For the same configuration condition, the fast NMOS fast PMOS (Fast The NMOS Fast PMOS, FF) corner swing may be large enough to affect the reliability of the circuit, but at the Slow NMOS Slow PMOS (SS) corner, there may be a problem that the VCO cannot oscillate, and at the same time At high temperatures, due to the decrease in the tank quality factor (Q), the starting ability is much worse than the low temperature. If you need to configure it separately for each scene, the following problems exist: The configuration according to the simulation Depending on the model conditions during simulation, it does not exactly match the actual situation; monitoring the working environment and process angle requires adding additional circuitry, increasing chip redundancy, test time and test cost.

Figure 1 is a circuit diagram of a resonant signal that uses an analog feedback scheme to regulate the VCO. The entire control process is a negative feedback process.

In the above analog feedback scheme, on the one hand, since the system is not an ideal linear system, to ensure the stability of the system negative feedback, the actual phase margin of the Opamp is difficult to design; on the other hand, the reference voltage Vref, the amplitude of the VCO, Vpeak and The noise of the op amp Opamp is mostly low-frequency flicker noise, which requires a large RC filter to eliminate, resulting in large area overhead and not easy to solve. On the other hand, the loop is in real-time working state. There is a certain amount of power consumption.

Summary of the invention

The embodiment of the invention provides an automatic amplitude control device and method, which has simple design, small area overhead and low power consumption.

In a first aspect, an automatic amplitude control apparatus is provided, the apparatus comprising: an oscillator and a current source array, one end of the current source array being coupled to a source of a cross-coupling tube in the oscillator, the current source The other end of the array is coupled to the ground, respectively; the device further includes: a comparator for comparing the amplitude detection signal of the oscillator with a reference voltage signal to obtain a comparison result; and a controller for performing the comparison result according to the comparison And controlling a current coupled to the source terminal by the current source array.

In the embodiment of the present invention, a digital feedback calibration process is introduced, and the amplitude detection signal of the oscillator is compared with the reference voltage signal by a comparator to obtain a comparison result, and then the controller controls the current source array to be coupled to the oscillator according to the comparison result. The current at the source of the cross-coupling tube. Due to the digital domain design, the circuit design is simplified, the design is simple, no filtering is required, and the area overhead is small, and after the calibration is completed, the circuit is in a silent state, does not contribute power consumption and noise, and thus consumes less power.

In a possible implementation, the current source array includes N parallel branches, each of which includes a series of switches and current sources, where N is an integer greater than 2; The comparison results respectively control the on and off of the switches in the respective branches to control the current coupled to the source terminal by the current source array. According to this embodiment, the on/off of the switch is controlled by the controller to control the current coupled to the source terminal by the current source array, which is simple in design.

In a possible implementation manner, the values of the current sources in the N branches of the current source array form a geometric progression, and the controller is configured to generate an N-bit control signal by using a binary search method to separately control the The switching of the switches in the N branches is described. According to this embodiment, the efficiency of the amplitude control is high by employing the binary search method.

In a possible implementation, the oscillator further includes a resonant cavity, the cross-coupling tube adopts an NMOS transistor, and the device further includes: a peak detecting circuit, configured to detect a magnitude of the resonant signal generated by the oscillator a minimum value; two inputs of the peak detection circuit are respectively coupled to two differential outputs of the resonant cavity; an output of the peak detection circuit is coupled to an input of the comparator. According to this embodiment, a manner of acquiring an amplitude detection signal of an oscillator is provided.

In a possible implementation, the oscillator further includes a resonant cavity, the cross-coupling tube adopts a PMOS tube, and the device further includes: a peak detecting circuit, configured to detect a magnitude of the resonant signal generated by the oscillator a maximum value; two inputs of the peak detection circuit are respectively coupled to two differential outputs of the resonant cavity; an output of the peak detecting circuit is coupled to an input of the comparator. According to this embodiment, another way of acquiring the amplitude detection signal of the oscillator is provided.

In a possible implementation, the input of the comparator is coupled to the source of the oscillator. According to this embodiment, since the amplitude of the signal at the source of the oscillator is related to the amplitude of the resonant signal generated by the oscillator, another way of obtaining the amplitude detection signal of the oscillator is provided.

In a possible implementation, the apparatus further includes: an Auto Band Select (ABS) circuit, configured to, at the controller, control the current source array to be coupled to the source according to the comparison result Selecting an operating frequency of the oscillator before the current of the terminal; and, after the controller controls the current coupled to the source by the current source array according to the comparison result, selecting the operating frequency of the oscillator again point. According to this embodiment, since the current source array is coupled to the source of the cross-coupling tube in the oscillator during the amplitude calibration of the oscillator, the frequency is slightly affected, so the amplitude calibration is combined with the ABS algorithm. Amplitude calibration is added to the two ABSs to ensure accurate frequency and ideal amplitude after the frequency configuration.

In a second aspect, an automatic amplitude control apparatus is provided for controlling the amplitude of a resonant signal generated by an oscillator, one end of which is coupled to a source of a cross-coupling tube in the oscillator, the current The other end of the source array is coupled to the ground, and the device includes: a comparison module, configured to compare the amplitude detection signal of the oscillator with a reference voltage signal to obtain a comparison result; and a control module, configured to obtain, according to the comparison module, As a result of the comparison, the current source array is coupled to the current at the source.

In a possible implementation, the current source array includes N parallel branches, each of which includes a series of switches and a current source, wherein N is an integer greater than 2; As a result, controlling the current coupled to the source terminal by the current source array includes: controlling on and off of the switches in the respective branches according to the comparison result to control current coupled to the source terminal by the current source array .

In a possible implementation manner, the values of the current sources in the N branches of the current source array form a geometric progression; the control module is specifically configured to generate an N-bit control signal by using a binary search method, The switching of the switches in the N branches is controlled separately.

In a possible implementation, the oscillator further includes a resonant cavity, the cross-coupling tube adopts an NMOS transistor, and the device further includes: a detecting module, configured to detect a magnitude of the resonant signal generated by the oscillator The minimum value is the minimum value of the amplitude of the resonance signal as the amplitude detection signal of the oscillator.

In a possible implementation, the oscillator further includes a resonant cavity, the cross-coupling tube adopts a PMOS tube, and the device further includes: a detecting module, configured to detect a magnitude of the resonant signal generated by the oscillator The maximum value is the maximum value of the amplitude of the resonance signal as the amplitude detection signal of the oscillator.

In a possible implementation, the apparatus further includes: a detecting module, configured to use a signal of a source end of the oscillator as an amplitude detecting signal of the oscillator.

In a possible implementation, the apparatus further includes: a frequency point selection module, configured to select the current before the comparison module controls the current source array coupled to the source terminal according to the comparison result An operating frequency point of the oscillator; and, after the comparing module controls the current coupled to the source terminal by the current source array according to the comparison result, selecting an operating frequency point of the oscillator again.

In a third aspect, an automatic amplitude control method is provided, the method comprising: comparing an amplitude detection signal of an oscillator with a reference voltage signal to obtain a comparison result; and, according to the comparison result, coupling to the oscillator The current of the current source array at the source of the cross-coupling tube is controlled.

In a possible implementation manner, the controlling, according to the comparison result, a current of a current source array coupled to a source end of the cross-coupling tube of the oscillator, comprising: coupling the pair according to the comparison result The switching of the switches in the respective branches of the current source array at the source of the cross-coupling tube of the oscillator is controlled to control the current coupled to the source terminal by the current source array.

In a possible implementation, the controlling the on and off of the switches in the respective branches of the current source array coupled to the source of the cross-coupling tube of the oscillator includes: generating a N by using a binary search method The bit control signal controls the switching of the switches in the N branches of the current source array coupled to the source of the cross-coupled tube of the oscillator, wherein N is an integer greater than two.

In a possible implementation manner, the method further includes: detecting a minimum value of the amplitude of the resonant signal generated by the oscillator, and using a minimum value of the amplitude of the resonant signal as the amplitude detecting signal of the oscillator.

In a possible implementation, the method further includes: detecting a maximum value of the amplitude of the resonant signal generated by the oscillator, and using a maximum value of the amplitude of the resonant signal as the amplitude detecting signal of the oscillator.

In a possible implementation, the method further includes: using a signal of a source end of the oscillator as an amplitude detection signal of the oscillator.

In a possible implementation, the method further includes: selecting a working frequency of the oscillator before the controlling the current source array coupled to the source according to the comparison result; and After controlling the current coupled to the source terminal by the current source array according to the comparison result, the operating frequency of the oscillator is selected again.

In a fourth aspect, an embodiment of the present invention provides a chip, where the chip can be disposed in a terminal, where the chip includes a processor and an interface. The processor is configured to support the chip to perform the corresponding functions of the method of the third aspect described above. This interface is used to support communication between the chip and other chips or other network elements. The chip can also include a memory for coupling with the processor that holds the necessary program instructions and data for the chip.

In a fifth aspect, an embodiment of the present invention provides a computer storage medium for storing computer software instructions used by the terminal, including a program designed to execute the foregoing third aspect.

In a sixth aspect, an embodiment of the present invention provides a computer program product, comprising instructions, which, when executed by a computer, cause a computer to perform the functions performed by the terminal in the method design of the third aspect above.

DRAWINGS

1 is a circuit diagram of a conventional resonant feedback scheme for adjusting the amplitude of a resonant signal of a VCO;

2A is a schematic structural diagram of an automatic amplitude control apparatus according to an embodiment of the present invention;

2B is a schematic structural diagram of another automatic amplitude control apparatus according to an embodiment of the present invention;

3 is a schematic structural diagram of another automatic amplitude control apparatus according to an embodiment of the present invention;

4 is a schematic diagram of relationship between automatic frequency band selection and automatic amplitude calibration according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of another automatic amplitude control apparatus according to an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of another automatic amplitude control apparatus according to an embodiment of the present invention;

FIG. 7 is a schematic structural diagram of another automatic amplitude control apparatus according to an embodiment of the present invention;

FIG. 8 is a flowchart of an automatic amplitude control method according to an embodiment of the present invention.

detailed description

2A is a schematic structural diagram of an automatic amplitude control apparatus according to an embodiment of the present invention. The apparatus includes an oscillator 201 (eg, a VCO) and a current source array 202. One end of the current source array 202 is coupled to the oscillator 201. a source end of the cross-coupling tube (also referred to as a common mode end), the other end of the current source array 202 being coupled to ground, respectively; the apparatus further comprising: a comparator 203 for using the oscillator 201 The amplitude detection signal is compared with the reference voltage signal to obtain a comparison result; the controller 204 is configured to control the current coupled to the source terminal by the current source array according to the comparison result.

It can be understood that the cross-coupling tube, which is the negative resistance generator of the VCO, can adjust the negative resistance of the VCO and adjust the amplitude of the VCO by adjusting the current coupled to the source end of the cross-coupling tube.

It can be understood that the values of the current sources in the N branches of the current source array may be the same or different. It is not necessary that the values of the current sources in the N branches of the current source array form a geometric progression, and are merely an alternative embodiment, exemplarily, in the N branches of the current source array The value of the current source can also constitute an arithmetic progression, or other form of sequence. It should be understood that when the values of the current sources in the N branches of the current source array are in an arithmetic progression, or other forms of series, the algorithm used by the controller in generating the N-bit control signal can refer to the prior art. , will not repeat them here.

In one example, the values of the current sources in the N branches of the current source array form a geometric progression and the ratio is 2, the controller is a Successive Approximation Register (SAR), and the SAR is used for An N-bit control signal is generated by a binary search method to respectively control the on and off of the switches in the N branches.

FIG. 2B is a schematic structural diagram of another automatic amplitude control apparatus according to an embodiment of the present invention. The apparatus includes: a comparator 211, configured to compare a magnitude of an amplitude detection signal and a reference voltage signal, where the amplitude detection signal may be a resonance of a VCO. The signal is either a signal related to the resonant signal of the VCO; the SAR 212 is configured to generate an N-bit control signal according to the output result of the comparator 211; the current source array 213 includes N current sources, wherein N is greater than two; The current source array 204 includes N current sources connected to the source end of the VCO through N switches; each of the N-bit control signals is used to control one of the N switches to be turned on. Or shut down.

In the embodiment of the present invention, a digital feedback calibration process is introduced, and the current source connected to the source end of the VCO is continuously adjusted by the SAR dichotomy, and the amplitude error of the VCO can be controlled to the least significant bit by successive approximation (Least Within the resolution range of Significant Bit (LSB), the design of the digital domain simplifies the circuit design, the design is simple, no filtering is required, and the area overhead is small, and the circuit is in a silent state after the calibration is completed, and does not contribute. Power consumption and noise, so power consumption is small.

It can be understood that the currents provided by the N current sources included in the current source array 204 may be the same or different. The number N of current sources may be any integer greater than or equal to 2. In actual design, the number N of current sources may be determined according to the accuracy of the amplitude of the resonant signal generated by the VCO. In one example, N=6, the ratio of the currents provided by any two of the N current sources is a multiple of 2, for example, the currents provided by the six current sources are ¹ unit, ² unit, 2 ² unit, respectively. 2 ³ unit, 2 ⁴ unit, 2 ⁵ unit, where the unit can be regarded as the unit of current magnitude, the accuracy of the amplitude control of the VCO can reach the accuracy of the current source control of the current of 1 unit, the current provided by the six current sources The ratio is 1:2:2 ² :2 ³ :2 ⁴ :2 ⁵ . According to this embodiment, the amplitude of the resonance signal generated by the VCO can be precisely controlled.

Among them, the algorithm adopted by SAR is the binary search method, and the algorithm is more efficient than other algorithms. SAR uses the "half-point search method" to generate digital quantities. Taking the 8-bit digital quantity as an example, the SAR first generates half of the 8-bit digital quantity, that is, 10000000B. The size of the analog quantity Vi (reference voltage) is tested, and the first voltage is represented by Vo. If Vo>Vi, clear the highest bit, if Vo<Vi, keep the highest bit. After the highest bit is determined, the SAR determines the second highest bit by the binary search method, that is, the size of the analog Vi is tested by half of the lower 7 bits y1000000B (y is the determined bit). After bit 6 is determined, the SAR determines the bit 5 bits by the binary search method, that is, the size of the analog quantity is tested by half of the lower 6 bits yy100000B (y is the determined bit). This process is repeated until the lowest bit 0 is determined and the automatic amplitude control ends.

Assuming that the amplitude detection signal Vpeak=0.4V, the reference voltage signal Vref=0.312V, and the voltage resolution corresponding to one current bit is 0.005V, the working process is roughly as follows:

The first step: i[5:0]=100000, (Vpeak=0.4V)>(Vref=0.312V), the comparator output 1;

The second step: i[5:0]=110000, (Vpeak=0.32V)>(Vref=0.312V), the comparator output 1;

The third step: i[5:0]=111000, (Vpeak=0.28V<(Vref=0.312V), the comparator outputs 0;

The fourth step: i[5:0]=110100, (Vpeak=0.32V)>(Vref=0.312V), the comparator output 1;

The fifth step: i[5:0]=110110, (Vpeak=0.315V)>(Vref=0.312V), the comparator output 1;

The sixth step: i[5:0]=110111, (Vpeak=0.31V)<(Vref=0.312V), the comparator outputs 0.

At this point, the comparison process is completed, and the obtained Vpeak and Vref deviation is smaller than the voltage resolution corresponding to one current bit. If a higher precision comparison result is required, the bit position can be increased and the resolution can be improved.

FIG. 3 is a schematic structural diagram of another automatic amplitude control apparatus according to an embodiment of the present invention. The apparatus includes: a comparator 301, configured to compare magnitudes of an amplitude detection signal and a reference voltage signal, where the amplitude detection signal is a resonant signal of a VCO. The controller 302 is configured to generate an N-bit control signal according to the output result of the comparator 301. In this embodiment, the controller 302 is a SAR; the current source array 303 includes N current sources, where N is greater than two; The N current sources included in the current source array 303 are connected to the source end of the VCO through N switches; one of the N-bit control signals is used to control one of the N switches to be turned on or Shutdown status.

It can be understood that the embodiment of the present invention does not limit the composition of the VCO. The composition of the VCO shown in Figure 3 is only an example. Referring to FIG. 3, the VCO includes a resonant cavity 304 and a cross-coupling tube 305, and the cross-coupling tube 305 employs an NMOS transistor. The apparatus further includes: a peak detection circuit 306 for detecting a minimum value of a magnitude of a resonance signal generated by the VCO (also referred to as an amplitude of a VCO); two inputs of the peak detection circuit 306 are respectively coupled to the Two differential outputs of the resonant cavity 304; the output of the peak detecting circuit 306 is coupled to the input of the comparator 301. According to this embodiment, one possible implementation of obtaining the magnitude of the VCO is provided.

In a possible implementation, the device further includes: an Auto Band Select (ABS) circuit 307, configured to select a working frequency of the VCO; the ABS circuit 307 has a state output terminal. The status output of the ABS circuit 307 is used to indicate the number of times the selection of the operating frequency of the VCO is completed, and the status output of the ABS circuit 307 is connected to the enable end of the controller 302; the controller 302 Having a status output, the status output of the controller 302 is used to indicate whether the automatic amplitude control of the VCO is completed, and the status output of the controller 302 is connected to the enable end of the ABS circuit 307; When the status output of the ABS circuit 307 indicates that the number of times the selection of the operating frequency of the VCO is completed is one, the enable end of the controller 302 is valid; when the status output of the controller 302 indicates completion When the automatic amplitude control of the VCO is described, the enable end of the ABS circuit 307 is valid. According to this embodiment, since the amplitude calibration of the VCO changes the tail current to have a slight influence on the frequency, the amplitude calibration is combined with the ABS algorithm, and the amplitude calibration is added to the two ABSs to ensure accurate frequency and frequency after the frequency point configuration. The ideal range.

It can be understood that the ABS circuit can adjust the operating frequency of the VCO after determining the operating frequency of the VCO, for example, by controlling the closed or open state of the switch connected in series with the capacitor in the VCO, thereby controlling the capacitance in the VCO. Correspondingly, the purpose of adjusting the working frequency of the VCO is achieved.

FIG. 4 is a schematic diagram of relationship between automatic frequency band selection and automatic amplitude calibration according to an embodiment of the present invention. Referring to Figure 4, the overall calibration process is described as follows:

When the VCO working frequency point is selected, the system needs to perform the ABS process first. When the first ABS is completed, the state machine enters the Auto Amplitude Calibration (AAC). After the AAC ends, the state machine returns to the initial state. State, the second ABS is performed until the ABS process is completed and the state machine exits. Since the amplitude calibration needs to adjust the tail current, this action will have a slight influence on the oscillation frequency of the VCO. In order to ensure the optimal band selection in the system application, the algorithm adopts an ABS process (ABS_ST1). Effective), the amplitude calibration is performed after the process is completed (AAC_END is effective), and the ABS (ABS_ST2 effective) is performed once the calibration is completed.

AAC process description: The peak detection circuit detects the lowest level of the resonance voltage, and obtains the output of 0/1 by comparison with the reference voltage Vref. The controller of the SAR generates a 6-bit control word according to the 0/1 signal to control. The switch of the current source at the tail of the VCO, the tail current source array adopts a binary ratio, that is, 1-2-4-8-16-32, and the dichotomy successive comparison process is completed 6 times. The size of Vpeak and Vref is compared by the comparator, and the output is 0/1. If the output is =0, the SAR uses the dichotomy to change Bit<5:0> downward. Otherwise, the dichotomy is upward, and the corresponding current source switch is turned on or off with Bit<5:0>, and the VCO swing is also With the increase or decrease, the process of successive comparisons finally makes the difference between Vpeak and Vref less than 1LSB.

Since the amplitude calibration changes the tail current of the VCO to slightly affect the resonant frequency of the VCO, the amplitude calibration is combined with the ABS algorithm, and the amplitude calibration is added to the two ABSs to ensure accurate frequency and ideal frequency after the frequency configuration. Amplitude.

FIG. 5 is a schematic structural diagram of another automatic amplitude control apparatus according to an embodiment of the present invention. The apparatus includes: a comparator 501, configured to compare a magnitude of an amplitude detection signal and a reference voltage signal, where the amplitude detection signal is a resonant signal of a VCO. The controller 502 is configured to generate an N-bit control signal according to the output result of the comparator 501. In this embodiment, the controller 302 is a SAR; the current source array 503 includes N current sources, where N is greater than two; The current source array 503 includes N current sources connected to the source end of the VCO through N switches; one of the N-bit control signals is used to control one of the N switches to be turned on or Shutdown status.

It can be understood that the embodiment of the present invention does not limit the composition of the VCO. The composition of the VCO shown in Fig. 5 is only an example. Referring to FIG. 5, the VCO includes a resonant cavity 504 and a cross-coupling tube 505. The cross-coupling tube 505 employs a PMOS transistor. The device further includes a peak detecting circuit 506 for detecting a maximum resonant signal generated by the VCO. The two inputs of the peak detecting circuit 506 are respectively connected to two differential outputs of the resonant cavity 504; the output of the peak detecting circuit 506 is connected to the input of the comparator 501. According to this embodiment, another possible implementation for obtaining the magnitude of the VCO is provided.

In a possible implementation, the device further includes: an ABS circuit 507 for selecting a working frequency of the VCO; the ABS circuit 507 has a state output, and the state output of the ABS circuit 507 is used. The number of times the selection of the operating frequency of the VCO is completed, the status output of the ABS circuit 507 is coupled to the enable end of the controller 502; the controller 502 has a status output, the controller The status output of the 502 is used to indicate whether the automatic amplitude control of the VCO is completed, the status output of the controller 502 is connected to the enable end of the ABS circuit 507; when the status output of the ABS circuit 507 is indicating When the number of times of selecting the operating frequency of the VCO is one, the enable end of the controller 502 is valid; when the status output of the controller 502 indicates that the automatic amplitude control of the VCO is completed, The enable end of the ABS circuit 507 is valid. According to this embodiment, since the amplitude calibration of the VCO changes the tail current to have a slight influence on the frequency, the amplitude calibration is combined with the ABS algorithm, and the amplitude calibration is added to the two ABSs to ensure accurate frequency and frequency after the frequency point configuration. The ideal range.

The relationship between the automatic band selection and the automatic amplitude calibration can be referred to FIG. 4 and the corresponding text description, and details are not described herein.

FIG. 6 is a schematic structural diagram of another automatic amplitude control apparatus according to an embodiment of the present invention. The apparatus includes: a comparator 601, configured to compare magnitudes of an amplitude detection signal and a reference voltage signal, where the amplitude detection signal is a source of a VCO The signal of the terminal is a signal related to the resonant signal; the controller 602 is configured to generate an N-bit control signal according to the output result of the comparator 601. In this embodiment, the controller 602 is a SAR; the current source array 603 Include N current sources, where N is greater than two; the current source array 603 includes N current sources connected to the source end of the VCO through N switches; one of the N-bit control signals is used for control signals One of the N switches is controlled to be in an on or off state.

It can be understood that the embodiment of the present invention does not limit the composition of the VCO. The composition of the VCO shown in Fig. 6 is only an example. In a possible implementation, the input of the comparator 601 is connected to the source end of the VCO. According to this embodiment, since the voltage at the source of the VCO is related to the magnitude of the VCO, yet another possible implementation for obtaining the magnitude of the VCO is provided. Since the peak detecting circuit is omitted in this manner, the occupied area can be further reduced.

In a possible implementation, the device further includes: an ABS circuit 604, configured to select a working frequency of the VCO; the ABS circuit 604 has a state output, and the state output of the ABS circuit 604 is used. The number of times the selection of the operating frequency of the VCO is completed, the status output of the ABS circuit 604 is coupled to the enable end of the controller 602; the controller 602 has a status output, the controller The status output of the 602 is used to indicate whether the automatic amplitude control of the VCO is completed, the status output of the controller 602 is connected to the enable end of the ABS circuit 604; when the status output of the ABS circuit 604 is indicating When the number of times of selecting the operating frequency of the VCO is one, the enabled end of the controller 602 is valid; when the status output of the controller 602 indicates that the automatic amplitude control of the VCO is completed, The enable end of the ABS circuit 604 is active. According to this embodiment, since the amplitude calibration of the VCO changes the tail current to have a slight influence on the frequency, the amplitude calibration is combined with the ABS algorithm, and the amplitude calibration is added to the two ABSs to ensure accurate frequency and frequency after the frequency point configuration. The ideal range.

In the embodiment of the present invention, the automatic amplitude calibration of the VCO is completed by the feedback method of the digital domain, the implementation manner is simple, the expandability is good, and the process node can be continuously evolved according to the process node, and the calibration circuit does not introduce additional noise, so the Large device area and RC filtering, no additional power consumption after the calibration process.

FIG. 7 is a schematic structural diagram of another automatic amplitude control apparatus according to an embodiment of the present invention. The apparatus is configured to control an amplitude of a resonant signal generated by an oscillator, and one end of the current source array is coupled to a cross-coupling tube in the oscillator. At the source end, the other end of the current source array is coupled to the ground, respectively, the device includes:

The comparison module 701 is configured to compare the amplitude detection signal of the oscillator with a reference voltage signal to obtain a comparison result;

The control module 702 is configured to control, according to the comparison result obtained by the comparison module 701, a current coupled to the source terminal by the current source array.

In one example, the current source array includes N parallel branches, each of which includes a series of switches and current sources, where N is an integer greater than two;

The control module 702 is specifically configured to control the on and off of the switches in the respective branches according to the comparison result obtained by the comparison module 701 to control the current coupled to the source terminal by the current source array.

In a possible implementation, the values of the current sources in the N branches of the current source array form a geometric progression; the control module 702 is specifically configured to generate an N-bit control signal by using a binary search method. To control the on and off of the switches in the N branches, respectively.

In a possible implementation, the apparatus further includes: a frequency point selection module, configured to select, before the comparison module 701 controls the current source array to be coupled to the source according to the comparison result An operating frequency point of the oscillator; and, after the comparing module controls the current coupled to the source terminal by the current source array according to the comparison result, selecting an operating frequency point of the oscillator again.

8 is a flowchart of an automatic amplitude control method according to an embodiment of the present invention, where the method is used to control the amplitude of a resonant signal generated by an oscillator, and one end of the current source array is coupled to a cross-coupling tube in the oscillator. At the source end, the other end of the current source array is coupled to the ground, respectively, the method includes:

Step 801, comparing the amplitude detection signal of the oscillator with a reference voltage signal to obtain a comparison result.

Step 802, according to the comparison result, controlling a current coupled to the source terminal by the current source array.

In a possible implementation manner, the values of the current sources in the N branches of the current source array form a geometric progression; the respectively controlling the switching of the switches in each branch, including: using a binary search The method generates an N-bit control signal to control the on and off of the switches in the N branches, respectively.

In a possible implementation, the oscillator further includes a resonant cavity, the cross-coupling tube adopts an NMOS transistor, and the method further includes: detecting a minimum value of a amplitude of the resonant signal generated by the oscillator, The minimum value of the amplitude of the resonant signal is used as the amplitude detection signal of the oscillator.

In a possible implementation, the oscillator further includes a resonant cavity, the cross-coupling tube adopts a PMOS transistor, and the method further includes: detecting a maximum value of a amplitude of the resonant signal generated by the oscillator, The maximum value of the amplitude of the resonant signal is used as the amplitude detection signal of the oscillator.

In a possible implementation, the signal at the source of the oscillator is used as the amplitude detection signal of the oscillator.

The embodiment of the invention further provides a chip device, the chip comprising a processing unit for performing the method shown in FIG. 8 above.

The embodiment of the invention further provides a chip device, which comprises a processor and a memory. The memory includes instructions that are executed by the processor for performing the method illustrated in FIG. 8 above.

In each of the above embodiments of the present invention, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in accordance with embodiments of the present invention are generated in whole or in part. The computer can be a general purpose computer, a special purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer readable storage medium or transferred from one computer readable medium to another computer readable medium, for example, the computer instructions can be wired from a website site, computer, server or data center (for example, coaxial cable, fiber, Digital Subscriber Line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) to another website, computer, server or data center. The computer readable storage medium can be any available media that can be accessed by a computer or a data storage device such as a server, data center, or the like that includes one or more available media. The usable medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a DVD), or a semiconductor medium (eg, a Solid State Disk (SSD)) or the like.

The specific embodiments of the present invention have been described in detail with reference to the preferred embodiments of the present invention. The scope of the protection, any modifications, equivalent substitutions, improvements, etc., which are made on the basis of the technical solutions of the present invention, are included in the scope of the present invention.

Claims

An automatic amplitude control device, characterized in that the device comprises:

An array of oscillators and current sources, one end of the current source array being coupled to a source of a cross-coupling tube in the oscillator, the other end of the current source array being coupled to ground, respectively; the apparatus further comprising:

a comparator, configured to compare an amplitude detection signal of the oscillator with a reference voltage signal to obtain a comparison result;

And a controller for controlling a current coupled to the source terminal by the current source array according to the comparison result.
The apparatus of claim 1 wherein said array of current sources comprises N parallel branches, each branch comprising a series of switches and current sources, wherein N is an integer greater than two; The controller is configured to respectively control the on and off of the switches in the respective branches according to the comparison result to control the current coupled to the source terminal by the current source array.
The apparatus according to claim 2, wherein values of current sources in the N branches of said current source array form a geometric progression, said controller for generating an N-bit control signal by a binary search method, To control the on and off of the switches in the N branches, respectively.
The device according to any one of claims 1 to 3, wherein the oscillator further comprises a resonant cavity, the cross-coupling tube adopts an NMOS transistor, and the device further comprises:

a peak detecting circuit for detecting a minimum value of a amplitude of a resonant signal generated by the oscillator;

Two input ends of the peak detecting circuit are respectively coupled to two differential outputs of the resonant cavity;

An output of the peak detection circuit is coupled to an input of the comparator.
The device according to any one of claims 1 to 3, wherein the oscillator further comprises a resonant cavity, the cross-coupling tube uses a PMOS tube, and the device further comprises:

a peak detecting circuit for detecting a maximum value of a amplitude of a resonant signal generated by the oscillator;

Two input ends of the peak detecting circuit are respectively coupled to two differential outputs of the resonant cavity;

An output of the peak detection circuit is coupled to an input of the comparator.
Apparatus according to any one of claims 1 to 3 wherein the input of the comparator is coupled to the source of the oscillator.
The device according to any one of claims 1 to 6, wherein the device further comprises:

An automatic band selection ABS circuit for selecting a working frequency of the oscillator before the controller controls the current coupled to the source terminal according to the comparison result; and

After the controller controls the current coupled to the source terminal by the current source array according to the comparison result, the operating frequency of the oscillator is selected again.
An automatic amplitude control method, the method comprising:

Comparing the amplitude detection signal of the oscillator with the reference voltage signal to obtain a comparison result;

Based on the comparison, the current of the current source array coupled to the source of the cross-coupled tube of the oscillator is controlled.
The method of claim 8 wherein:

The controlling, according to the comparison result, the current of the current source array coupled to the source end of the cross-coupled tube of the oscillator, comprising:

Controlling on and off of switches in respective branches of the current source array coupled to the source of the cross-coupled tube of the oscillator to control current coupled to the source terminal by the current source array based on the comparison .
The method of claim 9 wherein said controlling switching of switches in respective branches of the current source array coupled to the source of the cross-coupled tube of said oscillator comprises:

Generating an N-bit control signal using a binary search method to control switching of switches in N branches of a current source array coupled to a source of the cross-coupled tube of the oscillator, wherein N is greater than two Integer.
The method of any of claims 8 to 10, further comprising:

A minimum value of the amplitude of the resonance signal generated by the oscillator is detected, and a minimum value of the amplitude of the resonance signal is used as an amplitude detection signal of the oscillator.
The method of any of claims 8 to 10, further comprising:

A maximum value of the amplitude of the resonance signal generated by the oscillator is detected, and a maximum value of the amplitude of the resonance signal is used as an amplitude detection signal of the oscillator.
The method according to any one of claims 8 to 10, further comprising: using a signal of a source of the oscillator as an amplitude detection signal of the oscillator.
The method according to any one of claims 8 to 13, wherein the method further comprises:

Selecting an operating frequency point of the oscillator before controlling the current source array coupled to the source terminal according to the comparison result; and controlling the current source array coupling according to the comparison result After the current to the source, the operating frequency of the oscillator is again selected.