Current frequency conversion circuit, conversion method and inertial navigation device

Abstract

The application provides a current frequency conversion circuit, a conversion method and an inertial navigation device. The circuit comprises a current frequency conversion unit and a control unit. The current frequency conversion unit comprises an integration circuit, an ADC sampling circuit, a switch circuit and a constant current source circuit. The control unit comprises an ADC acquisition module, a constant current source control module, a pulse counting module, a temperature acquisition module, a temperature compensation processing module, a digital signal to pulse module and a pulse output module. The ADC acquisition module is connected with the ADC sampling circuit, the constant current source control module and the pulse counting module respectively. The constant current source control module is connected with the switch circuit. The temperature compensation processing module is connected with the pulse counting module, the temperature acquisition module and the digital signal to pulse module respectively. The pulse output module is connected with the digital signal to pulse module and a driving circuit respectively. The technical scheme of the application solves the technical problem that the system without the serial bus hardware condition cannot apply the software compensation and the hardware compensation precision cannot meet the requirement in the prior art.

Description

Technical Field

[0001] This invention relates to the field of current-frequency conversion technology, and in particular to a current-frequency conversion circuit, conversion method, and inertial navigation device. Background Technology

[0002] Current-to-frequency conversion circuits are increasingly widely used in inertial navigation. Their main function is to convert current signals into corresponding frequency signals, achieving pulse output. Traditional conversion circuits compensate for temperature drift using either hardware or software. Hardware compensation involves soldering a temperature-compensated current source and adjusting resistors to change the output current of the constant current source, thus adjusting the scaling factor. However, hardware compensation can only establish a linear compensation model based on the measured temperature point and has high requirements for the resistors themselves, making nonlinear compensation impossible. Software compensation establishes a temperature compensation model by collecting temperature sensor information. Currently, a full-temperature polynomial fitting formula is used for curve fitting. The compensation effect of this method depends on the order of the polynomial fitting formula; the higher the order, the better the compensation effect. Software compensation is superior to hardware compensation in terms of both accuracy and complexity. Because software compensation requires modeling the temperature information output, it uses a serial port for data output. However, some systems lack serial bus hardware and only support pulse-output current-to-frequency conversion circuits, but require high circuit compensation accuracy. Current hardware-compensated pulse-output current-to-frequency conversion circuits no longer meet the system requirements. Summary of the Invention

[0003] This invention provides a current-frequency conversion circuit, a conversion method, and an inertial navigation device, which can solve the technical problem in the prior art that systems without serial bus hardware conditions cannot apply software compensation while hardware compensation accuracy does not meet requirements.

[0004] According to one aspect of the present invention, a current-frequency conversion circuit is provided, the circuit comprising:

[0005] The current-frequency conversion unit includes an integrating circuit, an ADC sampling circuit, a switching circuit, and a constant current source circuit. The integrating circuit is connected to the output terminal of the accelerometer and the ADC sampling circuit, respectively, and the constant current source circuit is connected to the switching circuit and the integrating circuit, respectively.

[0006] The control unit includes an ADC acquisition module, a constant current source control module, a pulse counting module, a temperature acquisition module, a temperature compensation processing module, a digital signal to pulse conversion module, and a pulse output module. The ADC acquisition module is connected to the ADC sampling circuit, the constant current source control module, and the pulse counting module. The constant current source control module is connected to the switching circuit. The temperature compensation processing module is connected to the pulse counting module, the temperature acquisition module, and the digital signal to pulse conversion module. The pulse output module is connected to the digital signal to pulse conversion module and the drive circuit.

[0007] The system comprises the following components: an integrating circuit to convert the accelerometer's output current into an integrated voltage; an ADC sampling circuit to sample the integrated voltage; an ADC acquisition module to acquire the integrated voltage sampled by the ADC sampling circuit; a constant current source control module to compare the acquired integrated voltage with a preset threshold voltage, and to control the switching circuit to turn on the constant current source circuit to stabilize the current output when the acquired integrated voltage is higher than the threshold voltage; a pulse counting module to count output pulses based on the integrated voltage acquired by the ADC acquisition module; a temperature acquisition module to measure the current ambient temperature; a temperature compensation module to compensate the scaling factor based on the pulse count and the current ambient temperature to obtain a compensated scaling factor; a digital signal to pulse conversion module to convert the compensated scaling factor into a first pulse signal, extracting the decimal part of the compensated scaling factor for accumulation, converting it into a second pulse signal when an integer part appears in the accumulation, and performing a decimal operation on the accumulated value for subsequent accumulation; and a pulse output module to output the first and second pulse signals to the drive circuit.

[0008] Furthermore, the temperature compensation module is used to compensate the scaling factor based on the pulse count and the current ambient temperature using the following formula:

[0009]

[0010] K 拟合 =T 4 ×A4+T 3 ×A3+T 2 ×A2+T×A1+A0,

[0011] In the above formula, K 补 K is the compensated scaling factor. 拟合 K is the scaling factor fitted under the current ambient temperature. 标 K is the standard scaling factor at the current ambient temperature. 测 The pulse count values ​​are measured under the current temperature conditions, where T is the temperature and A0, A1, A2, A3, and A4 are the coefficients of each term.

[0012] Furthermore, the digital signal to pulse module is used to extract the decimal part of the compensated scaling factor according to the following formula:

[0013]

[0014] In the above formula, N 补 This refers to the decimal part of the scale factor after compensation.

[0015] Furthermore, the pulse output module is used to output a first pulse signal in the first half-cycle of the current signal conversion frequency and a second pulse signal in the second half-cycle of the current signal conversion frequency.

[0016] Furthermore, there are multiple threshold voltages.

[0017] Furthermore, the circuit also includes a serial port output module, which is connected to the temperature compensation processing module and is used to output the compensated scaling factor calculated by the temperature compensation processing module to the serial transceiver.

[0018] According to another aspect of the present invention, a method for performing current-frequency conversion using the aforementioned current-frequency conversion circuit of the present invention is provided, the method comprising:

[0019] The accelerometer's output current is converted into an integrated voltage using an integrating circuit.

[0020] The integrated voltage is sampled using an ADC sampling circuit, and the integrated voltage obtained by the ADC sampling circuit is acquired through an ADC acquisition module.

[0021] The constant current source control module compares the acquired integral voltage with the preset threshold voltage, and controls the switching circuit to turn on the constant current source circuit to stabilize the current output when the acquired integral voltage is higher than the threshold voltage.

[0022] The pulse counting module counts the output pulses based on the integrated voltage acquired by the ADC acquisition module, and the temperature acquisition module measures the current ambient temperature.

[0023] The scaling factor is compensated by the temperature compensation module based on the pulse count and the current ambient temperature to obtain the compensated scaling factor.

[0024] The digital signal to pulse module is used to convert the compensated scaling factor into a first pulse signal, and the decimal part of the compensated scaling factor is extracted and accumulated. When the integer part appears in the accumulation, it is converted into a second pulse signal, and the accumulated value is decimalized for subsequent accumulation.

[0025] The first and second pulse signals are output to the drive circuit through the pulse output module.

[0026] According to another aspect of the present invention, an inertial navigation device is provided, the inertial navigation device including the current frequency conversion circuit proposed above in the present invention.

[0027] The present invention provides a current-frequency conversion circuit, a conversion method, and an inertial navigation device. This circuit employs a multi-order fitting curve for temperature compensation, converting the compensated digital signal back into a pulse signal. Since pulse signals can only be integers, direct conversion would lose the fractional part of the digital signal. This circuit divides the pulse signal into an integer direct conversion part and a fractional compensation part, preserving the fractional information of the digital signal and achieving high-precision temperature compensation. Simultaneously, the output is a pulse signal, meeting the usage requirements of inertial navigation systems in hardware conditions without a serial bus. Attached Figure Description

[0028] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0029] Figure 1 A schematic diagram of the current-frequency conversion circuit provided according to a specific embodiment of the present invention is shown;

[0030] Figure 2 A schematic diagram of the output pulse structure provided according to a specific embodiment of the present invention is shown. Detailed Implementation

[0031] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0033] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0034] like Figure 1 As shown, a current-frequency conversion circuit is provided according to a specific embodiment of the present invention, the circuit comprising:

[0035] The current-frequency conversion unit includes an integrating circuit, an ADC sampling circuit, a switching circuit, and a constant current source circuit. The integrating circuit is connected to the output terminal of the accelerometer and the ADC sampling circuit, respectively, and the constant current source circuit is connected to the switching circuit and the integrating circuit, respectively.

[0036] The control unit includes an ADC acquisition module, a constant current source control module, a pulse counting module, a temperature acquisition module, a temperature compensation processing module, a digital signal to pulse conversion module, and a pulse output module. The ADC acquisition module is connected to the ADC sampling circuit, the constant current source control module, and the pulse counting module. The constant current source control module is connected to the switching circuit. The temperature compensation processing module is connected to the pulse counting module, the temperature acquisition module, and the digital signal to pulse conversion module. The pulse output module is connected to the digital signal to pulse conversion module and the drive circuit.

[0037] The system comprises the following components: an integrating circuit to convert the accelerometer's output current into an integrated voltage; an ADC sampling circuit to sample the integrated voltage; an ADC acquisition module to acquire the integrated voltage sampled by the ADC sampling circuit; a constant current source control module to compare the acquired integrated voltage with a preset threshold voltage, and to control the switching circuit to turn on the constant current source circuit to stabilize the current output when the acquired integrated voltage is higher than the threshold voltage; a pulse counting module to count output pulses based on the integrated voltage acquired by the ADC acquisition module; a temperature acquisition module to measure the current ambient temperature; a temperature compensation module to compensate the scaling factor based on the pulse count and the current ambient temperature to obtain a compensated scaling factor; a digital signal to pulse conversion module to convert the compensated scaling factor into a first pulse signal, extracting the decimal part of the compensated scaling factor for accumulation, converting it into a second pulse signal when an integer part appears in the accumulation, and performing a decimal operation on the accumulated value for subsequent accumulation; and a pulse output module to output the first and second pulse signals to the drive circuit.

[0038] This configuration provides a current-frequency conversion circuit that uses multi-order fitting curves for temperature compensation, converting the compensated digital signal back into a pulse signal. Since pulse signals can only be integers, direct conversion would lose the fractional part of the digital signal. This circuit divides the pulse signal into an integer direct conversion part and a fractional compensation part, preserving the fractional information of the digital signal and achieving high-precision temperature compensation. Simultaneously, the output is a pulse signal, meeting the requirements of inertial navigation systems operating without a serial bus hardware. Compared with existing technologies, this invention solves the technical problem that systems lacking serial bus hardware cannot apply software compensation while hardware compensation accuracy is insufficient.

[0039] Furthermore, in this embodiment of the invention, the temperature compensation processing module employs a digital temperature compensation method. It obtains a polynomial fitting formula (including the order and coefficients of each term) by curve fitting based on the temperature and the count value of the digital pulse signal. Based on this polynomial fitting formula, the scaling factor at the set ambient temperature can be obtained, and then compensation is performed by combining it with a standard scaling factor. Specifically, the temperature compensation processing module compensates for the scaling factor based on the pulse count and the current ambient temperature using the following formula:

[0040]

[0041] K 拟合 =T 4 ×A4+T 3 ×A3+T 2 ×A2+T×A1+A0,

[0042] In the above formula, K 补K is the compensated scaling factor. 拟合 K is the scaling factor fitted under the current ambient temperature. 标 K is the standard scaling factor at the current ambient temperature. 测 The pulse count values ​​are measured under the current temperature conditions, where T is the temperature and A0, A1, A2, A3, and A4 are the coefficients of each term.

[0043] The set standard scaling factor K 标 The scaling factor K fitted to the ambient temperature value 拟合 The ratio is approximately 1. If the standard scaling factor is set too high, the ratio will be greater than 1. Then, the difference between the compensated scaling factor and the measured scaling factor is obtained by multiplying the decimal part of the ratio by the measured pulse count value.

[0044] In the process of converting the compensated scaling factor into a pulse signal, the compensation calculation results in a decimal part in the compensated scaling factor. If the integer part of the compensated scaling factor is directly converted into a pulse, the decimal part will be lost. Therefore, in the process of converting digital signals to pulse signals, the compensated part (decimal part) is extracted and converted into a pulse separately. Specifically, in this embodiment of the invention, the digital signal to pulse module extracts the decimal part of the compensated scaling factor according to the following formula:

[0045]

[0046] In the above formula, N 补 This refers to the decimal part of the scale factor after compensation.

[0047] Because the single conversion compensation amount (decimal part) is too small to generate a single pulse, this invention accumulates the compensation amount each time, performs pulse conversion after superposition, and continues to perform decimal operation on the superposition amount after conversion. In this way, once the superposition amount has an integer part, it can be converted into a pulse amount in time. At the same time, by performing decimal operation after conversion, it can avoid continuing to superimpose the converted integer part.

[0048] Based on the above embodiments, in this embodiment of the invention, the pulse output module outputs a first pulse signal, i.e., the measured scaling factor pulse, during the first half-cycle of the current signal conversion frequency, and outputs a second pulse signal, i.e., the compensated scaling factor pulse, during the second half-cycle of the current signal conversion frequency. In this way, the measured pulse and the compensated pulse are transmitted in a regular manner.

[0049] Furthermore, in this embodiment of the invention, there are multiple threshold voltages. By setting multiple thresholds through ADC sampling values, the conversion resolution can be expanded, enabling the pulse output current-frequency conversion circuit to achieve the conversion resolution and compensation accuracy of a digital output circuit.

[0050] Furthermore, in order to adapt to different inertial navigation system hardware conditions, such as Figure 1 As shown in the embodiment of the invention, the circuit further includes a serial port output module, which is connected to the temperature compensation processing module and is used to output the compensated scaling factor calculated by the temperature compensation processing module to the serial transceiver. This configuration enables compatibility between serial port output and pulse output, adapting to different inertial navigation system hardware conditions.

[0051] To gain a further understanding of the present invention, the following description is provided in conjunction with... Figure 1 and Figure 2 The current-frequency conversion circuit of the present invention will be described in detail.

[0052] like Figure 1 As shown, in practical applications, the current-frequency conversion circuit includes a current-frequency conversion unit, a control unit, and an interface unit. The current-frequency conversion unit connects to the accelerometer, converting the accelerometer's output current into an integral voltage. A constant current source circuit then stabilizes the output current. The control unit compares the integral voltage with a preset threshold voltage and outputs a proportional digital pulse. The control unit uses an FPGA controller to perform functions such as comparing the integral voltage, controlling the constant current source, calculating digital pulse compensation, converting digital signals to pulses, and outputting the pulse. The FPGA's logic modules mainly include an ADC acquisition module, a constant current source control module, a temperature acquisition module, a pulse counting module, a temperature compensation processing module, a digital signal to pulse conversion module, a serial port output module, and a pulse output module. The ADC acquisition module acquires the integral voltage and compares the voltage value with a preset threshold voltage. When the integral voltage is lower than the threshold, it outputs a low level; when the integral voltage is higher than the threshold, it outputs a high level, activating the constant current source circuit and putting the current-frequency conversion circuit into the feedback phase. The pulse counting module counts the output pulses and sends the count value to the temperature compensation processing module. The temperature compensation processing module compensates the scaling factor across the entire temperature range using a temperature compensation algorithm to obtain the compensated scaling factor. The digital signal to pulse module then converts the compensated scaling factor into a pulse signal.

[0053] In the process of converting the compensated scaling factor into a pulse signal, the compensation calculation results in a decimal part in the scale factor. If the integer part of the compensated scaling factor is directly converted into a pulse, the decimal part will be lost. Therefore, in the process of converting digital signals into pulse signals, the compensation part is extracted and converted into a pulse separately. Since the compensation amount in a single conversion is too small to produce a single pulse, the compensation amounts are accumulated and then converted into pulses. After conversion, the accumulated amount is further rounded down to the decimal part. In this way, once the accumulated amount has an integer part, it can be converted into a pulse quantity in time. At the same time, the decimal part is rounded down after conversion to avoid the continued accumulation of the converted integer part.

[0054] The output pulse structure of the pulse output module is as follows: Figure 2 As shown, during the real-time conversion of digital signals to pulse signals, the current signal conversion frequency is 128kHz, and the maximum number of pulses in a single conversion is 8. Therefore, the output pulse frequency in a 128kHz cycle should be 1.024MHz. However, due to the presence of compensation pulses, there may be 1 to 8 compensation pulses in a single conversion cycle. Therefore, the output pulse frequency in a single conversion cycle increases to 2.048MHz. The measured scaling factor pulse is output in the first half of the 128kHz cycle, and the compensated scaling factor pulse is output in the second half. Based on the above embodiment, the pulse output type current frequency conversion circuit can achieve a temperature compensation accuracy of 0.5ppm / ℃.

[0055] According to another aspect of the present invention, a method for performing current-frequency conversion using the aforementioned current-frequency conversion circuit of the present invention is provided, the method comprising:

[0056] The accelerometer's output current is converted into an integrated voltage using an integrating circuit.

[0057] The integrated voltage is sampled using an ADC sampling circuit, and the integrated voltage obtained by the ADC sampling circuit is acquired through an ADC acquisition module.

[0058] The constant current source control module compares the acquired integral voltage with the preset threshold voltage, and controls the switching circuit to turn on the constant current source circuit to stabilize the current output when the acquired integral voltage is higher than the threshold voltage.

[0059] The pulse counting module counts the output pulses based on the integrated voltage acquired by the ADC acquisition module, and the temperature acquisition module measures the current ambient temperature.

[0060] The scaling factor is compensated by the temperature compensation module based on the pulse count and the current ambient temperature to obtain the compensated scaling factor.

[0061] The digital signal to pulse module is used to convert the compensated scaling factor into a first pulse signal, and the decimal part of the compensated scaling factor is extracted and accumulated. When the integer part appears in the accumulation, it is converted into a second pulse signal, and the accumulated value is decimalized for subsequent accumulation.

[0062] The first and second pulse signals are output to the drive circuit through the pulse output module.

[0063] According to another aspect of the present invention, an inertial navigation device is provided, comprising the current-frequency conversion circuit proposed above. Since the current-frequency conversion circuit proposed above can achieve high-precision temperature compensation and outputs a pulse signal, it can meet the usage requirements of inertial navigation systems under hardware conditions without a serial bus. Therefore, its application in an inertial navigation device can significantly improve its performance.

[0064] In summary, this invention provides a current-frequency conversion circuit, a conversion method, and an inertial navigation device. This circuit uses a multi-order fitting curve for temperature compensation, converting the compensated digital signal back into a pulse signal. Since pulse signals can only be integers, direct conversion would lose the fractional part of the digital signal. This circuit divides the pulse signal into an integer direct conversion part and a fractional compensation part, preserving the fractional information of the digital signal and achieving high-precision temperature compensation. Simultaneously, the output is a pulse signal, meeting the usage requirements of inertial navigation systems without serial bus hardware. Compared with existing technologies, the technical solution of this invention solves the technical problem that systems lacking serial bus hardware cannot apply software compensation while hardware compensation accuracy is insufficient.

[0065] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0066] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A current-to-frequency conversion circuit, characterized by, The circuit includes: A current-frequency conversion unit includes an integrating circuit, an ADC sampling circuit, a switching circuit, and a constant current source circuit. The integrating circuit is connected to the output terminal of the accelerometer and the ADC sampling circuit, respectively, and the constant current source circuit is connected to the switching circuit and the integrating circuit, respectively. The control unit includes an ADC acquisition module, a constant current source control module, a pulse counting module, a temperature acquisition module, a temperature compensation processing module, a digital signal to pulse conversion module, and a pulse output module. The ADC acquisition module is connected to the ADC sampling circuit, the constant current source control module, and the pulse counting module. The constant current source control module is connected to the switching circuit. The temperature compensation processing module is connected to the pulse counting module, the temperature acquisition module, and the digital signal to pulse conversion module. The pulse output module is connected to the digital signal to pulse conversion module and the driving circuit. The system comprises the following components: an integrating circuit converting the accelerometer's output current into an integrated voltage; an ADC sampling circuit sampling the integrated voltage; an ADC acquisition module acquiring the integrated voltage sampled by the ADC sampling circuit; a constant current source control module comparing the acquired integrated voltage with a preset threshold voltage, and controlling the switching circuit to activate the constant current source circuit to stabilize the current output when the acquired integrated voltage exceeds the threshold voltage; a pulse counting module counting output pulses based on the integrated voltage acquired by the ADC acquisition module; a temperature acquisition module measuring the current ambient temperature; a temperature compensation module compensating the scaling factor based on the pulse count and the current ambient temperature to obtain a compensated scaling factor; a digital signal to pulse conversion module converting the compensated scaling factor into a first pulse signal, extracting the decimal part of the compensated scaling factor for accumulation, converting the accumulated value into a second pulse signal when an integer part appears, and performing a decimal operation on the accumulated value for subsequent accumulation; and a pulse output module outputting the first pulse signal and the second pulse signal to the driving circuit.

2. The circuit of claim 1, wherein, The temperature compensation module is used to compensate the scaling factor based on the pulse count and the current ambient temperature using the following formula: K 拟合 = T 4 × A4 + T 3 × A3 + T 2 × A2 + T × A1 + A0, In the above formula, K 补 is the compensated scale factor, K 拟合 is the scale factor fitted at the current ambient temperature, K 标 is the standard scale factor at the current ambient temperature, K 测 is the measured pulse count value at the current temperature environment, T is the temperature, and A0, A1, A2, A3, and A4 are the coefficients of the respective terms.

3. The circuit of claim 2, wherein, The digital signal to pulse module is used to extract the decimal part of the compensated scaling factor according to the following formula: In the above equation, N 补 is the fractional part of the compensated scale factor.

4. The circuit of claim 1, wherein, The pulse output module is used to output a first pulse signal in the first half of the current signal conversion frequency cycle and a second pulse signal in the second half of the current signal conversion frequency cycle.

5. The circuit of claim 1, wherein, There are multiple threshold voltages.

6. The circuit of any one of claims 1 to 5, wherein, The circuit also includes a serial port output module, which is connected to the temperature compensation processing module and is used to output the compensated scaling factor calculated by the temperature compensation processing module to the serial transceiver.

7. A method of current frequency conversion using the current frequency conversion circuit according to any one of claims 1 to 6, characterized by, The method includes: The accelerometer's output current is converted into an integrated voltage using an integrating circuit. The integral voltage is sampled using an ADC sampling circuit, and the integral voltage sampled by the ADC sampling circuit is acquired by an ADC acquisition module. The constant current source control module compares the acquired integral voltage with the preset threshold voltage, and controls the switching circuit to turn on the constant current source circuit to stabilize the current output when the acquired integral voltage is higher than the threshold voltage. The pulse counting module counts the output pulses based on the integrated voltage acquired by the ADC acquisition module, and the temperature acquisition module measures the current ambient temperature. The scaling factor is compensated by the temperature compensation module based on the pulse count and the current ambient temperature to obtain the compensated scaling factor. The digital signal to pulse module is used to convert the compensated scaling factor into a first pulse signal, and the decimal part of the compensated scaling factor is extracted and accumulated. When the integer part appears in the accumulation, it is converted into a second pulse signal, and the accumulated value is decimalized for subsequent accumulation. The first pulse signal and the second pulse signal are output to the drive circuit through the pulse output module.

8. An inertial navigation device, characterized by The inertial navigation device includes the current-frequency conversion circuit according to any one of claims 1 to 6.

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