阅读说明：本技术 一种时钟信号生成电路及电子设备 (Clock signal generating circuit and electronic equipment ) 是由 杨家奇 黄正乙 于 2018-07-17 设计创作，主要内容包括：一种时钟信号生成电路及电子设备,所述电路包括：ROSC模块,适于生成时钟信号；参考时钟模块,连接所述ROSC模块,所述参考时钟模块适于提供参考时钟信号；温度传感器,连接所述ROSC模块,适于感测所述ROSC模块的工作温度；存储模块,连接所述温度传感器和所述ROSC模块,适于存储温度误差校正表,所述温度误差校正表中记录有针对所述工作温度的微调数据；所述ROSC模块初始化时或者所述工作温度超出预设温度范围时,所述ROSC模块利用所述参考时钟模块校正所述时钟信号的频率；否则,利用针对所述工作温度的微调数据校正所述时钟信号的频率。通过本发明提供的技术方案,可以在保证时钟精度的前提下,降低功耗。(A clock signal generation circuit and an electronic device, the circuit comprising: a ROSC module adapted to generate a clock signal; a reference clock module connected to the ROSC module, the reference clock module adapted to provide a reference clock signal; the temperature sensor is connected with the ROSC module and is suitable for sensing the working temperature of the ROSC module; the storage module is connected with the temperature sensor and the ROSC module and is suitable for storing a temperature error correction table, and fine tuning data aiming at the working temperature are recorded in the temperature error correction table; when the ROSC module is initialized or the working temperature exceeds a preset temperature range, the ROSC module utilizes the reference clock module to correct the frequency of the clock signal; otherwise, the frequency of the clock signal is corrected using the fine tuning data for the operating temperature. By the technical scheme provided by the invention, the power consumption can be reduced on the premise of ensuring the clock precision.)

1. A clock signal generation circuit, comprising:

a ROSC module adapted to generate a clock signal;

a reference clock module connected to the ROSC module, the reference clock module adapted to provide a reference clock signal;

the temperature sensor is connected with the ROSC module and is suitable for sensing the working temperature of the ROSC module;

the storage module is connected with the temperature sensor and the ROSC module and is suitable for storing a temperature error correction table, and fine tuning data aiming at the working temperature are recorded in the temperature error correction table;

when the ROSC module is initialized or the working temperature exceeds a preset temperature range, the ROSC module utilizes the reference clock module to correct the frequency of the clock signal; otherwise, the ROSC module corrects the frequency of the clock signal using the trim data for the operating temperature.

2. The clock signal generation circuit of claim 1, wherein the ROSC module is a current mode type ROSC module.

3. The clock signal generation circuit of claim 1, wherein the storage module further stores:

the system comprises a ROSC module, a process error correction table and a control module, wherein fine tuning data aiming at the process error of the ROSC module are recorded in the process error correction table;

when the ROSC module completes initialization and the working temperature falls into the preset temperature range, the ROSC module also utilizes the process error correction table to correct the frequency of the clock signal.

4. The clock signal generation circuit of claim 3, wherein a bit width of the trim data recorded by the process error correction table is adapted to a lowest clock precision of the ROSC module.

5. The clock signal generation circuit according to claim 1, wherein a bit width of the trimming data recorded in the temperature error correction table is adapted to a number of temperature sections into which the preset temperature range is divided.

6. The clock signal generation circuit of claim 1, wherein the storage module further stores: the temperature correction table records fine adjustment data aiming at errors caused by temperature changes;

and the ROSC module corrects the frequency of the clock signal by using the trimming data in the temperature error correction table and the temperature correction table.

7. The clock signal generation circuit according to any one of claims 1 to 6, wherein the storage module is a nonvolatile memory.

8. The clock signal generation circuit according to any one of claims 1 to 6, wherein the preset temperature range is 0 ℃ to 80 ℃.

9. The clock signal generation circuit of any of claims 1 to 6, wherein the reference clock module starts operating when the ROSC module is initialized or the operating temperature exceeds a preset temperature range, and otherwise the reference clock module stops operating.

10. An electronic device characterized by comprising the clock signal generation circuit of any one of claims 1 to 9.

Technical Field

The present invention relates to the field of electronic circuit technologies, and in particular, to a clock signal generation circuit and an electronic device.

Background

With the rapid development of the Internet of Things (IOT), the electronic device has higher and higher requirements for low power consumption. Since almost all modern electronic system designs are based on clock signals, which are the basis for the proper operation of the electronic device, the electronic device is usually provided with a clock signal generating circuit.

The Clock signal may be generated by a Real Time Clock (RTC) crystal oscillator or a Ring oscillator (Ring oscillator). The RTC crystal oscillator has the disadvantages of large power consumption, large volume and high price. The structure of the RTC crystal can be divided into a digital circuit part and an analog circuit part. In order to reduce the power consumption of the RTC crystal oscillator, the digital circuit portion may use a Low Dropout Linear Regulator (LDO) for voltage reduction; the power consumption of the analog circuit portion is still high, however, resulting in a current consumption of at least 350 nanoamps (i.e., nA). In addition, since the RTC chip requires a crystal (crystal) in addition to the RTC circuit, the price thereof is always high. ROSC has the disadvantage of low frequency accuracy and frequency instability. The existing ROSC optimization schemes mainly comprise two types: one is to use an external Bluetooth Low Energy (BLE) signal to periodically correct the frequency, but increase the current consumption in milliampere (mA) level; the other is to adopt a Process Voltage Temperature (PVT) sensor for correction, and the power consumption of the PVT sensor is also in milliamp level.

Currently, there is still a lack of clock signal generation circuits that meet both the accuracy and low power consumption requirements.

Disclosure of Invention

The invention solves the technical problem of reducing the power consumption of a clock signal generating circuit on the premise of ensuring the frequency precision.

To solve the above technical problem, an embodiment of the present invention provides a clock signal generation circuit, including: a ROSC module adapted to generate a clock signal; a reference clock module connected to the ROSC module, the reference clock module adapted to provide a reference clock signal; the temperature sensor is connected with the ROSC module and is suitable for sensing the working temperature of the ROSC module; the storage module is connected with the temperature sensor and the ROSC module and is suitable for storing a temperature error correction table, and fine tuning data aiming at the working temperature are recorded in the temperature error correction table; when the ROSC module is initialized or the working temperature exceeds a preset temperature range, the ROSC module utilizes the reference clock module to correct the frequency of the clock signal; otherwise, the ROSC module corrects the frequency of the clock signal using the trim data for the operating temperature.

Optionally, the ROSC module is a current mode type ROSC module.

Optionally, the storage module further stores: the system comprises a ROSC module, a process error correction table and a control module, wherein fine tuning data aiming at the process error of the ROSC module are recorded in the process error correction table; when the ROSC module completes initialization and the working temperature falls into the preset temperature range, the ROSC module also utilizes the process error correction table to correct the frequency of the clock signal.

Optionally, the bit width of the fine tuning data recorded by the process error correction table is adapted to the lowest clock precision of the ROSC module.

Optionally, the bit width of the fine tuning data recorded in the temperature error correction table is adapted to the number of the temperature intervals divided by the preset temperature range.

Optionally, the storage module further stores: the temperature correction table records fine adjustment data aiming at errors caused by temperature changes; and the ROSC module corrects the frequency of the clock signal by using the trimming data in the temperature error correction table and the temperature correction table.

Optionally, the storage module is a nonvolatile memory.

Optionally, the preset temperature range is 0 ℃ to 80 ℃.

Optionally, when the ROSC module is initialized or the operating temperature exceeds a preset temperature range, the reference clock module starts to operate, otherwise, the reference clock module stops operating.

In order to solve the above technical problem, an embodiment of the present invention further provides an electronic device, including the clock signal generating circuit.

Compared with the prior art, the technical scheme of the embodiment of the invention has the following beneficial effects:

an embodiment of the present invention provides a clock signal generating circuit, including: a ROSC module adapted to generate a clock signal; a reference clock module connected to the ROSC module, the reference clock module adapted to provide a reference clock signal; the temperature sensor is connected with the ROSC module and is suitable for sensing the working temperature of the ROSC module; the storage module is connected with the temperature sensor and the ROSC module and is suitable for storing a temperature error correction table, and fine tuning data aiming at the working temperature are recorded in the temperature error correction table; when the ROSC module is initialized or the working temperature exceeds a preset temperature range, the ROSC module utilizes the reference clock module to correct the frequency of the clock signal; otherwise, the ROSC module corrects the frequency of the clock signal using the trim data for the operating temperature. According to the technical scheme provided by the embodiment of the invention, the reference clock module providing the parameter clock signal is only used in the initialization process and when the temperature is too high or too low, the power consumption is reduced on the premise of ensuring the precision compared with the mode of completely using the reference clock module, the correction is carried out in the preset temperature range by combining the temperature sensor with the temperature error correction table, and compared with the mode of completely using the PVT sensor for correction, the temperature range applicable to the temperature sensor is smaller, the error of the clock signal is smaller, so that the temperature sensor can be realized by adopting the low-power-consumption design, and the power consumption is favorably saved.

Furthermore, the ROSC module is a current mode ROSC module, and the voltage effect can be eliminated by adopting the current mode ROSC module, so that the error caused by voltage is avoided, and the precision of a clock signal is improved.

Further, the storage module further stores: the system comprises a ROSC module, a process error correction table and a control module, wherein fine tuning data aiming at the process error of the ROSC module are recorded in the process error correction table; when the ROSC module completes initialization and the working temperature falls into the preset temperature range, the ROSC module also utilizes the process error correction table to correct the frequency of the clock signal. The frequency deviation of the ROSC module caused by the process error can be eliminated through the fine tuning data recorded by the process error correction table.

Furthermore, the bit width of the fine tuning data recorded in the temperature error correction table is adapted to the number of temperature intervals divided by the preset temperature range, and the temperature error correction table can eliminate the frequency deviation caused by the ROSC module due to temperature change, so as to correct the frequency of the clock signal.

Drawings

Fig. 1 is a schematic block diagram of a clock signal generation circuit according to an embodiment of the present invention;

FIG. 2 is a graph illustrating the frequency versus temperature of a clock signal output by an exemplary ROSC module;

FIG. 3 is a schematic diagram of frequency deviation of the clock signal generating circuit shown in FIG. 1 caused by temperature variation at different times;

fig. 4 is a block diagram showing an exemplary configuration of a clock signal generation circuit of the clock signal generation circuit shown in fig. 1.

Detailed Description

As background art, the existing clock signal generation circuit has high precision, high price and large power consumption; or the precision is low, the power consumption is small, and both the requirement of the electronic equipment on the low power consumption and the higher precision of the clock signal generating circuit are difficult to meet.

The inventor of the present application finds that, as electronic products are miniaturized and highly integrated, requirements of electronic devices on area and power consumption are higher and higher, and a clock signal generating circuit in the electronic device should reduce power consumption as much as possible on the premise of maintaining clock accuracy.

Among them, the Ring oscillator (Ring oscillator, ROSC for short) is particularly suitable for being applied to various electronic devices due to its simple structure, small area and low power consumption. However, since the ROSC is not feedback-controlled, the frequency of the output clock signal is easily affected by factors such as a process, an operating temperature, and a power supply voltage, and thus there are problems that the frequency is unstable and the clock accuracy is not high. Therefore, in the existing scheme, a trimming circuit is usually added in the design, so that the frequency after trimming meets the requirement of design precision.

A trimming circuit can use an external Bluetooth Low Energy (BLE) signal to periodically correct the frequency of a ROSC clock signal, but the BLE signal can increase current consumption, taking normally working BLE as an example, enabling the BLE will consume about 10mA current, and if the BLE is used for a long time, the Low power consumption benefit brought by ROSC will be offset by the BLE.

Another modification circuit may use a Process Voltage Temperature (PVT) sensor to correct the frequency of the clock signal. If a PVT sensor is used to correct the frequency of the ROSC clock signal, the PVT sensor must be continuously operated to ensure that the ROSC does not distort the frequency due to process, voltage, and temperature variations. However, the power consumption of the PVT sensor is also in the milliamp level, and it is difficult to meet the low power consumption requirement of the electronic device.

To solve the above technical problem, an embodiment of the present invention provides a clock signal generating circuit, including: a ROSC module adapted to generate a clock signal; a reference clock module connected to the ROSC module, the reference clock module adapted to provide a reference clock signal; the temperature sensor is connected with the ROSC module and is suitable for sensing the working temperature of the ROSC module; the storage module is connected with the temperature sensor and the ROSC module and is suitable for storing a temperature error correction table, and fine tuning data aiming at the working temperature are recorded in the temperature error correction table; when the ROSC module is initialized or the working temperature exceeds a preset temperature range, the ROSC module utilizes the reference clock module to correct the frequency of the clock signal; otherwise, the ROSC module corrects the frequency of the clock signal using the trim data for the operating temperature.

According to the technical scheme provided by the embodiment of the invention, the reference clock module providing the parameter clock signal is only used in the initialization process and when the temperature is too high or too low, the power consumption is reduced on the premise of ensuring the precision compared with the condition that the reference clock module is used completely, the correction is carried out in a preset temperature range by combining the temperature sensor with the temperature error correction table, and compared with the condition that the PVT sensor is used completely for correction, the temperature range applicable to the temperature sensor is smaller, the error of the clock signal is smaller, so that the temperature sensor can be realized by adopting a low-power-consumption design, and the power consumption is favorably saved.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

Fig. 1 is a clock signal generation circuit according to an embodiment of the present invention. The clock signal generation circuit 100 may include: a memory module 1, a ROSC module 2, a reference clock module 3 and a temperature sensor 4.

In particular, the ROSC module 2 is adapted to generate a clock signal. When the ROSC module 2 generates a clock signal, the generated current consumption is about 100nA, the power consumption is very low, and the ROSC module 2 has the advantages of simple structure, small area and the like, can replace a RTC module with relatively high price, and is applied to various electronic devices.

Preferably, the ROSC module 2 may be a current mode type ROSC module. The conventional ROSC module may affect the clock accuracy due to the voltage drift, and in the conventional scheme, a voltage sensor may be added to sense the voltage and compensate the frequency deviation caused by the voltage drift, but sensing the voltage in real time not only increases the volume of the clock signal generating circuit 100, but also is difficult to meet the requirement of low power consumption. The current mode type ROSC module can keep stable voltage, cannot cause output voltage oscillation due to input voltage change, and is not easily influenced by voltage, so that the ROSC module 2 cannot influence clock precision due to voltage change, can solve the problem of voltage drift, and is suitable for low-power-consumption design.

Further, the temperature sensor 4 may be connected to the ROSC module 2 and the reference clock module 3, and adapted to sense an operating temperature of the ROSC module 2. In particular, the temperature sensor 4 may be configured to sense a wafer (die) temperature of the ROSC module 2, thereby obtaining the operating temperature. After determining the operating temperature, the clock signal generation circuit 100 may determine to control the ROSC module 2 to generate the clock signal using the reference clock module 3 or the memory module 1.

Further, the reference clock module 3 may be connected to the ROSC module 2. When the ROSC module 2 is initialized or the operating temperature of the ROSC module 2 exceeds a preset temperature range, the ROSC module 2 can correct the frequency of the clock signal by using the reference clock module 3. When the ROSC module 2 is initialized or the working temperature exceeds a preset temperature range, the reference clock module 3 starts to work. If the operating temperature is within the preset temperature range, the reference clock module 3 may stop operating to save power consumption.

Preferably, the preset temperature range may be 0 ℃ to 80 ℃. As shown in FIG. 2, the prior art (H.Asano, T.Hirose, T.Miyoshi, K.Tsubaki, Sub-1-mus Start-up Time,32-MHz Relay cooler for Low-Power Intermitent VLSI systems design Automation conference,35-36,2017) indicates that the change of the ROSC operating temperature curve is relatively smooth between 0 ℃ and 80 ℃ and has less influence on the clock precision of the ROSC output; the ROSC operating temperature profile is relatively severe at the remaining temperatures (e.g., -20 ℃ to 0 ℃ and 80 ℃ to 125 ℃) and has a large effect on clock accuracy. In addition, 0 ℃ to 80 ℃ is also a common temperature range in a typical application scenario of the clock generation circuit, and thus, 0 ℃ to 80 ℃ can be used as the preset temperature.

Preferably, the reference clock module 3 may be a BLE module. The reference clock module 3 may also be selected from a Zigbee (Zigbee) module, a Near Field Communication (NFC) module, a Wi-Fi module, and the like. The reference clock module 3 can be connected to the internet or other wireless communication networks to obtain a network clock signal as a reference clock signal. As is well known, the network clock signal is a clock signal with high clock accuracy, and can be used to correct the frequency of the clock signal generated by the ROSC module 2.

As a non-limiting example, the ROSC module 2 outputs a ROSC clock signal according to a BLE signal (which may be, for example, a clock signal generated by the BLE module), that is, the BLE signal controls the clock signal generation circuit 100 to generate the clock signal.

As a non-limiting example, the reference clock module 3 may be an internal module of an electronic device, independently present in the ROSC module 2; or may be integrated with the ROSC module 2.

As an embodiment, when the wafer temperature (i.e., the operating temperature) of the clock signal generation circuit 100 is 0 ℃ to 80 ℃, the reference clock module 3 stops operating, and when the wafer temperature reaches 100 ℃ or more, the ROSC module 2 generates a ROSC clock signal according to the clock signal of the reference clock module 3.

Further, the memory module 1 may connect the ROSC module 2 and the temperature sensor 4. The storage module 1 stores trimming data, and may be a non-volatile memory. The trimming data stored therein does not disappear after the power is turned off.

Further, the storage module 1 stores a process error correction table (not shown). The process error correction table records therein fine adjustment data for the process error of the ROSC module 2. When the ROSC module 2 completes initialization and the operating temperature falls within the preset temperature range, the ROSC module 2 may further correct the frequency of the clock signal by using the process error correction table.

In particular, the ROSC module 2 can configure associated devices to compensate for frequency deviations according to the process error correction table. The process error refers to a clock signal with frequency change generated by ROSC due to the error generated by the fast and slow running of the device. However, under certain circumstances, the process error of the fixed device operation, the fixed wafer, will be a deterministic value, and the frequency variation of the clock signal of the ROSC will also be determined as a deterministic value. Thus, based on the determined process error, the frequency of the clock signal of the ROSC can be determined under the process error. Based on the determined frequency deviation introduced by the process error, compensation information of the frequency deviation for different conditions, i.e. fine tuning data for the process error of the ROSC module 2, can be recorded in a process error correction table.

As a non-limiting example, the bit width of the trim data recorded by the process error correction table may be adapted to the lowest clock precision of the ROSC module 2 to meet the precision requirements of the clock signal. The ROSC module 2 may output a clock signal based on the trim data in the process error correction table.

Further, the storage module 1 is further adapted to store a temperature error correction table (not shown), in which the fine tuning data for the operating temperature is recorded. The ROSC module 2 can correct the frequency of the clock signal with the fine tuning data for the operating temperature.

As a non-limiting example, the trim data for the operating temperature may include any number of bits, may represent any temperature range, and may be subdivided into any number of smaller (or larger) steps.

Preferably, the working temperature may be a preset temperature of 0 ℃ to 80 ℃, and the fine tuning data may be corresponding fine tuning data between 0 ℃ and 80 ℃. In a specific implementation, the operating temperature of the ROSC module 2 is considered to vary smoothly within a preset temperature range between 0 ℃ and 80 ℃, so that real-time sensing of the operating temperature is not required. In addition, the temperature sensor 4 may adopt a low power consumption design, the detected temperature range is much smaller than that of the prior art, so that the low power consumption design is possible, and the frequency error of the clock signal is smaller in the temperature range, for example, the temperature sensor may be a 3 μ a operating current, and the operating temperature may be sensed every 5 seconds or 10 seconds.

In one non-limiting embodiment, the bit width of the fine tuning data recorded in the temperature error correction table may be adapted to the number of temperature intervals into which the preset temperature range is divided. For example, 2 bits of data are used to respectively represent the fine tuning data corresponding to the following 4 temperature intervals: 0 ℃ to 30 ℃, 31 ℃ to 50 ℃, 51 ℃ to 70 ℃ and 71 ℃ to 80 ℃.

As a non-limiting example, if the temperature sensed by the temperature sensor 4 for the first time is 15 ℃, the ROSC module 2 corrects the frequency of the generated clock signal according to the trimming data corresponding to the temperature interval of 0 ℃ to 30 ℃.

As a further non-limiting example, if the temperature sensed by the temperature sensor 4 for the first time is 44 ℃, the ROSC module 2 corrects the frequency of the generated clock signal according to the trimming data corresponding to the temperature interval of 31 ℃ to 50 ℃.

Those skilled in the art will appreciate that other numbers of bits may be used to characterize trim data for different temperature ranges and that many more embodiments may be varied in practice.

After the temperature sensor 4 senses the current working temperature, obtaining fine tuning data of a temperature error correction table associated with the current working temperature according to the temperature range of the current working temperature; the ROSC module 2 may correct the frequency of the clock signal based on the trimming data stored in each of the process error correction table and the temperature error correction table.

Further, the storage module 1 may further store a temperature correction table (not shown). The temperature correction table may have recorded therein fine adjustment data for an error caused by a temperature change. Specifically, since a frequency deviation may be introduced due to a temperature change simply by storing the time by the past time and the current time, and when the introduced frequency deviation reaches a certain threshold, the accuracy of the clock signal generated by the ROSC module 2 is low, and therefore, the frequency deviation information introduced by sensing the temperature twice can be represented by adding the temperature correction information. In consideration of the fact that the temperature variation within the preset temperature range is smooth, a 1-bit temperature correction table may be used to characterize the frequency deviation.

Specifically, the temperature correction table may be configured such that, after the ROSC module 2 is initialized, the temperature sensor 4 senses the temperature, calculates a frequency deviation caused by a temperature change due to a temperature change in two temperature sensing times from a temperature change initially sensed by the temperature sensor 4, and records the frequency deviation in the temperature correction table.

More specifically, after the temperature sensor 4 first senses the temperature, a temperature error correction value may be determined from the sensed temperature, and a clock signal may be generated in conjunction with the trim data for the process error. Thereafter, after sensing the temperature a second time, the frequency deviation introduced by the temperature change may be determined from the two sensed temperatures. If the temperature sensed by the temperature sensor at the current time and the last sensed temperature change, and the temperature change causes an error generated by the frequency of the clock signal to be greater than a preset threshold, the frequency of the clock signal can be corrected based on the temperature correction table.

Because the temperature change in the preset temperature range approaches to linear change, the temperature correction table is adopted to store related data, and the frequency deviation caused by each temperature change can be determined by only once calculation, so that the calculation operation can be reduced, and the power consumption can be saved.

As a non-limiting example, the frequency deviation of the clock signal caused by the temperature change may be calculated by the pythagorean theorem. Specifically, as shown in fig. 3, the shaded area is a frequency deviation from the past time T1 to the current time T2 due to a temperature change. The count value corresponding to the current time T2 can be determined according to the temperature of the current time T2 sensed by the temperature sensor 4, and similarly, the count value corresponding to the past time T1 can also be determined. Due to the fact that the temperature change curve is smooth, the frequency deviation can be approximately calculated by means of the Pythagorean theorem, and the frequency deviation caused by temperature change can be represented by the correction information of the floating point number of 1 bit so as to correct the clock signal.

The temperature correction table may be represented by a 1-bit floating point number. In practical applications, based on the bit information, the clock signal generating circuit 100 can configure the associated device to compensate the frequency deviation, so that the ROSC module 2 is not affected by temperature and outputs a clock signal meeting the precision requirement.

Then, according to the temperature variation condition, combining the accumulated error of the temperature correction table and combining the temperature error correction table, when the accumulated error exceeds the preset threshold, the ROSC module 2 corrects the frequency of the clock signal by using the fine tuning data in the temperature error correction table and the temperature correction table; otherwise, the ROSC module 2 still corrects the frequency of the clock signal using the fine tuning data in the temperature error correction table.

Accordingly, the ROSC module 2 can configure the associated device in combination with the trimming data recorded in the process error correction table, the temperature error correction table, and the temperature correction table to correct the frequency of the clock signal, so that the ROSC module 2 is not affected by temperature and process and outputs the clock signal meeting the precision requirement.

The process error correction table, the temperature error correction table, and the temperature correction table stored in the storage module 1 will be described below by taking a permanent calendar with an average monthly error of only one second and a half second precision as an example.

As shown in fig. 4, the clock signal generation circuit 200 may include a memory module 1, a ROSC module 2, a reference clock module 3, and a temperature sensor 4. The external load module 5 receives the clock signal from the clock signal generating circuit 200.

Wherein the temperature sensor 4 is connected with the ROSC module 2; the storage module 1 is connected with the ROSC module 2 and the temperature sensor 4; the storage module 1 stores a temperature error correction table 12, and the temperature error correction table 12 records fine tuning data for the working temperature; the storage module 1 further stores a process error correction table 11, and fine tuning data for a process error of the ROSC module is recorded in the process error correction table 11; the storage module 1 further stores a temperature correction table 13, and the temperature correction table 13 records fine adjustment data for errors caused by temperature changes. It should be noted that the memory module 1, the ROSC module 2, the reference clock module 3, and the temperature sensor 4 shown in fig. 4 can refer to the memory module 1, the ROSC module 2, the reference clock module 3, and the temperature sensor 4 shown in fig. 1, respectively, and are not described herein again.