Integrated circuit for multifunctional processing of sensor signals

Abstract

The utility model discloses a sensor signal multifunctional processing integrated circuit which comprises an amplification circuit module arranged at a sensor signal input end and a filter circuit module arranged at a sensor signal output end, and the amplification circuit module is externally connected with an excitation current circuit module. An open circuit and short circuit detection circuit module is also connected between the sensor signal input end and the amplification circuit module; according to the scheme, the signal processing module is reasonable in structure, high in technical maturity and high in reliability, programmable excitation current and adjustable amplification gain are achieved, and different requirements for signal processing can be met.

Description

Technical Field

[0001] The utility model relates to the technical field of IEPE sensor signal conditioning, and particularly relates to an integrated circuit for multi-functional processing of sensor signals. Background Art

[0002] In modern electronic devices, signal processing technology is a commonly used electronic circuit design technology for processing input signals such as amplification, filtering, AC coupling, excitation current, etc., and simultaneously realizing functions such as short circuit and open circuit detection, ±10V signal range detection, etc.

[0003] In some industrial environments, it is necessary to transmit the front-end sensor signal to the back-end device, but it is necessary to ensure that the signal transmitted to the back-end device can be directly used to avoid damage to the back-end device caused by excessive signals. Signal processing technology can effectively process the front-end signal into the signal required by the back-end device.

[0004] With the development of industry, although signal processing technology has wide applications and importance in electronic circuit design, there are also some technical deficiencies and disadvantages, such as:

[0005] (1) The limitation of excitation current, different sensors require different excitation currents;

[0006] (2) The adaptability of the amplification factor is insufficient, and different application scenarios have different requirements for the amplification factor;

[0007] (3) The selection of filter parameters is insufficient, and different sensors have different ranges of filtering frequencies;

[0008] (4) High manufacturing cost, etc. Content of the Utility Model

[0009] Based on the above problems, the utility model proposes an integrated circuit for multi-functional processing of sensor signals, and the specific technical solutions are as follows.

[0010] An integrated circuit for multi-functional processing of sensor signals includes an amplification circuit module arranged at the sensor signal input end and a filtering circuit module arranged at the sensor signal output end. The amplification circuit module is externally connected to an excitation current circuit module, and an open circuit and short circuit detection circuit module is also connected between the sensor signal input end and the amplification circuit module; the output end of the filtering circuit module is also connected to a range detection circuit module.

[0011] Specifically, the amplification circuit module includes a signal filtering circuit and a signal amplification circuit. The input end of the signal filtering circuit is connected to the positive of the sensor signal input, and it also includes a filter composed of a filtering capacitor and a resistor connected. The output end of the filter is connected to the filtering signal output end AMP0+ of the signal filtering circuit.

[0012] Specifically, the output terminal AMP0+ of the filtered signal is connected to the positive signal input port of the amplifier in the amplifier circuit, and the signal output port of the amplifier is connected to the amplified signal output terminal PGA_OUT_0, and the amplified signal output terminal PGA_OUT_0 is connected to the filter circuit module.

[0013] Specifically, the filter circuit module includes a fourth-order low-pass filter, and also includes two dual operational amplifiers connected in sequence. A resistor is connected in series with each of the two dual operational amplifiers, and a capacitor is connected in parallel. A capacitor is connected between each dual operational amplifier and the series resistor and grounded. The two dual operational amplifiers are also connected by a resistor; two resistors are also connected in series at the input of the dual operational amplifier near the input terminal of the filter circuit module, and a capacitor is connected between the two resistors and grounded; the output of the fourth-order low-pass filter is connected to the output terminal Fillter_out_0.

[0014] Specifically, the range detection circuit module includes a general operational amplifier and two dual comparators respectively connected to the general operational amplifier. The positive input terminal of the general operational amplifier is connected to the output terminal of the filter circuit module, and the negative input terminal is connected to the output terminal.

[0015] Specifically, for the two dual comparators, the negative input terminal of comparator one is connected to the positive input terminal of comparator two. The positive input terminal of comparator one is connected to a positive voltage input, and the negative input terminal of comparator two is also connected to a negative voltage input; the output terminals of the two dual comparators are respectively connected to two pull-up resistors, and a resistor and a triode are connected between each group of the two pull-up resistors.

[0016] Specifically, the input terminal of the open / short detection circuit module is connected to the positive sensor signal input; the open / short detection circuit module includes two parallel dual comparators. The negative input terminal of comparator one and the positive input terminal of comparator two are connected to the positive sensor signal input. The positive input terminal of comparator one is externally connected to a voltage and is grounded after being connected to the negative input terminal of comparator two.

[0017] Specifically, the output terminals of comparator one and comparator two of the open / short detection circuit module are both connected to two pull-up resistors, and a triode is connected between each group of the two pull-up resistors. The output of comparator one is connected to the output terminal OPEN_REE, and the output of comparator two is connected to the output terminal SHORT_ERR.

[0018] Specifically, the input end of the excitation current circuit module is connected to the positive of the sensor signal input. The input end is connected to the current emitter of the excitation current circuit module through a parallel connection of a triode and a field effect transistor. The VIN pin of the current emitter is connected to the VOUT output pin of the DAC chip, and a pull-up resistor is externally connected to each of the SCKL pin and the SDA pin of the DAC chip.

[0019] Advantages of the present utility model: The present utility model provides an integrated circuit for multi-functional processing of sensor signals. The signal processing module has a reasonable structure, a high degree of technological maturity, and strong reliability, and has a programmable excitation current and an adjustable amplification gain. The proposed solution adopts a programmable circuit structure in the excitation current circuit and the amplification circuit, enabling the excitation circuit to freely output within the range of 1 - 20 mA, and having an adjustable amplification gain of 1, 2, 5, and 10 times. This makes the structure of the signal processing module simple and capable of meeting different requirements for signal processing. Brief Description of the Drawings

[0020] Figure 1 is the overall architecture diagram of the integrated circuit for multi-functional processing of sensor signals in an embodiment of the present utility model;

[0021] Figure 2 is the circuit diagram of the signal filtering circuit module in an embodiment of the present utility model;

[0022] Figure 3 is the circuit diagram of the filtering circuit module in an embodiment of the present utility model;

[0023] Figure 4 is the circuit diagram of the range detection circuit module in an embodiment of the present utility model;

[0024] Figure 5 is the circuit diagram of the open circuit and short circuit detection circuit module in an embodiment of the present utility model;

[0025] Figure 6 is the circuit diagram of the excitation current circuit module in an embodiment of the present utility model. Detailed Embodiments

[0026] For a clearer understanding of the technical features, objectives, and effects of the present utility model, the specific embodiments of the present utility model will now be described with reference to the accompanying drawings.

[0027] An integrated circuit for multi-functional processing of sensor signals, as Figure 1 shown, includes an amplification circuit module provided at the sensor signal input end and a filtering circuit module provided at the sensor signal output end. The amplification circuit module is externally connected to an excitation current circuit module, and an open circuit and short circuit detection circuit module is also connected between the sensor signal input end and the amplification circuit module; the output end of the filtering circuit module is also connected to a range detection circuit module.

[0028] In this embodiment, the excitation current circuit module superimposes the excitation current on the sensor signal. The sensor signal is subjected to open - circuit and short - circuit detection, then reaches the amplifier circuit module for signal amplification, and then reaches the filter circuit module for signal filtering. After the filtering is completed, the output signal is output, and at the same time, the signal range is detected by the range detection circuit module.

[0029] The excitation current circuit module is used to output the excitation current.

[0030] The open - circuit and short - circuit detection circuit module is used for open - circuit and short - circuit detection of the sensor signal.

[0031] The amplifier circuit module is used for amplifying the sensor signal.

[0032] The filter circuit module is used for filtering the sensor signal.

[0033] The range detection circuit module is used for detecting the range of the output signal.

[0034] In a preferred embodiment, the amplifier circuit module is as Figure 2 shown, and includes a signal filter circuit and a signal amplifier circuit. The input end of the signal filter circuit is connected to the positive input of the sensor signal IEPE_SIg_OUT_CH0. It also includes a filter composed of a filter capacitor C41 and a resistor R28. The output end of the filter is connected to the filtered signal output end AMP0+ of the signal filter circuit. In this embodiment, the other end of the resistor R28 is grounded. A resistor R27 is also connected between the filter composed of the filter capacitor C41 and the resistor R28 and the output end AMP0+. A grounded capacitor C40 is connected between the resistor R27 and the output end AMP0+. In addition, the resistor R27 is also connected to another output end AMP0 - through a capacitor C42, and the connection line is also grounded respectively through a resistor R29 and a capacitor C43.

[0035] In this embodiment, the filtered signal output end AMP0+ is connected to the positive signal input port IN+ (pin 1) of the amplifier U12 in the amplifier circuit. The signal output port OUT (pin 7) of the amplifier U12 is connected to the amplified signal output end PGA_OUT_0, and the amplified signal output end PGA_OUT_0 is connected to the filter circuit module.

[0036] In this embodiment, the specific operation of the signal amplifier circuit includes that IEPE_SIg_OUT_CH0 is the positive input of the sensor signal; Figure 2 Among them, C41 and R28 form a filter, filter the incoming signal and then reach AMP0+. U12 is an amplifier, amplify the signal input to AMP0+, and the amplified signal is output from PGA_OUT_0 and reaches Figure 3 .

[0037] In a preferred embodiment, the filter circuit module is as Figure 3 shown, including a fourth-order low-pass filter, and further including two dual operational amplifiers U14A and U14B connected in sequence. Each dual operational amplifier is connected in series with a resistor and then connected in parallel with a capacitor. A capacitor is connected between the dual operational amplifier and the series resistor and grounded. The two dual operational amplifiers are also connected to each other through a resistor. Specifically in this embodiment: The dual operational amplifier U14A is connected in series with a resistor R39 and then connected in parallel with a capacitor C48. A capacitor C52 is connected between the dual operational amplifier U14A and the resistor R39 and grounded; The dual operational amplifier U14B is connected in series with a resistor R41 and then connected in parallel with a capacitor C49. A capacitor C54 is connected between the dual operational amplifier U14B and the resistor R41 and grounded; The dual operational amplifiers U14A and U14B are connected through a resistor R40; Two resistors R37 and R38 are also connected in series at the input end of the dual operational amplifier U14A close to the filter circuit module. A capacitor C51 is connected between R37 and R38 and grounded.

[0038] In this embodiment, the fourth-order low-pass filter is jointly composed of capacitors C51, C52, C54, C48, and C49. The output of the fourth-order low-pass filter is connected to the output terminal Fillter_out_0.

[0039] In this embodiment, the specific operation of the filter circuit includes: as Figure 3 shown, PAG_OUT_0 is Figure 2 the amplified signals U1, U21 are triodes, U14A and U14B are a dual operational amplifier, and together with resistors R37, R38, R39, R40, R41, and capacitors C51, C52, C48, C54, C48, they form a fourth-order low-pass filter. The signal bandwidth is adjusted by adjusting the values of the above-mentioned resistors and capacitors. The signal is input from PAG_OUT_0 and reaches the fourth-order low-pass filter, and after filtering, it is output from Fiter_out_0 and reaches Figure 4 .

[0040] In a preferred embodiment, as Figure 4 shown, the range detection circuit module includes a general operational amplifier U20 and two dual comparators U17A and U17B respectively connected to the general operational amplifier U20. The positive input terminal of the general operational amplifier U20 is connected to the output terminal of the filter circuit module, that is, the output terminal Fillter_out_0; the negative input terminal is connected to the output terminal.

[0041] In this embodiment, there are two dual comparators U17A and U17B. The negative input terminal of the first dual comparator U17A is connected to the positive input terminal of the second dual comparator U17B. The positive input terminal of the first dual comparator U17A is connected to a positive voltage input with a voltage value of +10V. The negative input terminal and the output terminal of the second dual comparator U17B are also connected to a negative voltage input with a voltage value of -10V. The output terminals of the two dual comparators are respectively connected to two pull-up resistors. Each pull-up resistor is externally connected to a voltage of +3.3V. A resistor and a triode are connected between each group of the two pull-up resistors. Specifically, the first dual comparator U17A is connected to resistors R45 and R44. A resistor R48 and a triode U18 are connected between resistors R45 and R44. The second dual comparator U17B is connected to resistors R54 and R53. A resistor R58 and a triode U21 are connected between resistors R54 and R53.

[0042] In this embodiment, the specific operation of the range detection circuit includes: As Figure 4 , Fiter_out_0 is Figure 3 the filtered signal, U20 is a general operational amplifier, U17A and U17B are a dual comparator. Resistors R45, R54, R44, and R53 are externally connected to +3.3V and act as pull-up resistors. Here, the 3rd pin of U20 is connected to the 4th pin to form a voltage follower function, following the signal of Fiter_out_0 to R52. Through R52, it reaches OUT_CHO and the 2nd pin of U17A and the 5th pin of U17B, and is compared with the voltages of the 3rd pin of U17A and the 6th pin of U17B. When the signals of the 2nd pin of U17A and the 5th pin of U17B are within the voltage range of the 3rd pin of U17A and the 6th pin of U17B, the voltages of the 1st pin of U17A and the 7th pin of U17B are 3.3V. The voltages of the 1st pin of U17A and the 7th pin of U17B respectively reach the bases of triodes U16 and U21 through resistors R48 and R58, and the collector and emitter are turned on, and Range_+10V_CH0 and Range_-10V_CH0 output high levels.

[0043] When the signals of the 2nd pin of U17A and the 5th pin of U17B exceed the voltage of the 3rd pin of U17A and do not exceed the voltage of the 6th pin of U17B, the 1st pin of U17A is at a negative voltage, the voltage of the 7th pin of U17B is 3.3V, the base of triode U16 is at a negative voltage, triode U16 is not turned on, Range_+10V_CH0 outputs a low level, the base of triode U15 is 3.3V, triode U21 is turned on, and Range_-10V_CH0 outputs a high level.

[0044] Similarly, when the signals at pins 2 of U17A and 5 of U17B exceed the voltage at pin 6 of U17B but do not exceed the voltage at pin 3 of U17A, the base of transistor U16 is at 3.3V, transistor U16 conducts, Range_+10V_CH0 outputs a high level, the base of transistor U15 is at a negative voltage, transistor U21 does not conduct, and Range_-10V_CH0 outputs a low level.

[0045] In a preferred embodiment, as Figure 5 shown, the input end of the open / short detection circuit module is connected to the positive sensor signal input IEPE_SIg_OUT_CH0; the open / short detection circuit module includes two parallel dual comparators U18A and U18B. The negative input terminal of the first dual comparator U18A and the positive input terminal of the second dual comparator U18B are connected to the positive sensor signal input IEPE_SIg_OUT_CH0. The positive input terminal of the first dual comparator U18A is externally connected to the voltage VSP_24V and is grounded after being connected to the negative input terminal of the second dual comparator U18B.

[0046] In this embodiment, the output terminals of the first and second dual comparators U18A and U18B of the open / short detection circuit module are both connected to two pull-up resistors. A transistor is connected between each group of the two pull-up resistors. Each pull-up resistor is externally connected to the voltage +3.3V. Specifically, the first dual comparator U18A is connected to resistors R49 and R47, and the second dual comparator U18B is connected to resistors R56 and R57; the output of the first dual comparator U18A is connected to the output terminal OPEN_REE, and the output of the second dual comparator U18B is connected to the output terminal SHORT_ERR.

[0047] In this embodiment, the specific operation of the open / short detection circuit includes: as Figure 5 shown, IEPE_SIg_IN_CH0 is the positive sensor signal input, U18A and U18B are a dual comparator, U19 and U22 are transistors, and resistors R49, R47, R57, and R56 are externally connected to +3.3V and act as pull-up resistors; Figure 2 in which C61 and R50 form a filter for Figure 5Filter the input signal of IEPE_SIg_IN_CH0. The filtered signal is connected to pin 2 of U18A and pin 5 of U18B, and compared with pin 3 of U18A and pin 6 of U18B. VSP_24V is a 24V voltage. Resistors R46, R55, and R60 are used for voltage division here. The voltage at pin 3 of U18A is [R55 + R60 / R46 + R55 + R60] * 24 ≈ 11V, and the voltage at pin 5 of U18B is [R60 / R46 + R55 + R60] * 24 ≈ 1.7V. When the signals at pin 2 of U18A and pin 5 of U18B are within the signals at pin 3 of U18A and pin 6 of U18B, the voltages at pin 1 of U18A and pin 7 of U18B are 3.3V. The voltages at pin 1 of U18A and pin 7 of U18B reach the bases of transistors U19 and U22 through resistors R51 and R59 respectively, and the collectors and emitters are conducting, and OPEN_ERR and SHORT_ERR output high levels.

[0048] When the signals at pin 2 of U18A and pin 5 of U18B exceed the voltage at pin 6 of U18B and do not exceed the voltage at pin 3 of U18A, the voltage at pin 1 of U18A is 3.3V, the voltage at pin 7 of U18B is negative voltage, the base of transistor U22 is negative voltage, transistor U22 is not conducting, SHORT_ERR outputs low level, the base of transistor U19 is 3.3V, transistor U19 is conducting, and OPEN_ERR outputs high level.

[0049] Similarly, when the signals at pin 2 of U18A and pin 5 of U18B exceed the voltage at pin 3 of U18B and do not exceed the voltage at pin 3 of U18B, the base of transistor U22 is 3.3V, transistor U22 is conducting, SHORT_ERR outputs high level, the base of transistor U19 is negative voltage, transistor U19 is not conducting, and OPEN_ERR outputs low level.

[0050] In a preferred embodiment, as Figure 6 shown, the input end of the excitation current circuit module is connected to the positive of the sensor signal input IEPE_SIg_OUT_CH0. The input end is connected to the current emitter U13 of the excitation current circuit module through the parallel-connected transistor Q1 and field effect transistor Q2. The VIN pin of the current emitter U13 is connected to the VOUT output pin of the DAC core U15. The SCKL pin and SDA pin of the DAC chip U15 are externally connected to pull-up resistors R42 and R43 respectively, and each pull-up resistor is externally connected to the voltage +3.3V.

[0051] In this embodiment, the specific operation of the excitation current circuit includes: as Figure 6As shown, IEPE_SIg_IN_CH0 is the positive sensor signal input, U13 is a current transmitter, Q1 and Q2 are a triode and a field effect transistor respectively, U15 is a DAC chip, R42 and R43 are pull-up resistors. The output voltage signal of U15 is controlled by IIC and connected to pin 6 of U13 through pin 1 to control the output excitation current signal of U13. After passing through Q1 and Q2 to enhance the driving ability, it reaches Figure 6 above IEPE_SIg_IN_CH0 in Figure 6 , providing an excitation current of 1 - 20 mA for the outside. The output voltage of U15 is proportional to the output current of U13: 0 - 5 V corresponds to 0 - 20 mA.

[0052] The above shows and describes the basic principles, main features and advantages of the present utility model. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principle of the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the present utility model claimed. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents.

Claims

1. An integrated circuit for multifunctional processing of sensor signals, characterized in that: It includes an amplifier circuit module arranged at the sensor signal input end and a filter circuit module arranged at the sensor signal output end. The amplifier circuit module is externally connected to an excitation current circuit module, and an open circuit and short circuit detection circuit module is also connected between the sensor signal input end and the amplifier circuit module; the output end of the filter circuit module is also connected to a range detection circuit module.

2. The integrated circuit for multifunctional processing of sensor signals according to claim 1, characterized in that: The amplifier circuit module includes a signal filtering circuit and a signal amplifying circuit. The input end of the signal filtering circuit is connected to the sensor signal input positive, and also includes a filter composed of a filter capacitor and a resistor. The output end of the filter is connected to the signal filtering circuit filter signal output end AMP0+.

3. The integrated circuit for multifunctional processing of sensor signals according to claim 2, characterized in that: The filter signal output terminal AMP0+ is connected to the signal input positive port of the amplifier in the amplifier circuit, the signal output port of the amplifier is connected to the amplified signal output terminal PGA_OUT_0, and the amplified signal output terminal PGA_OUT_0 is connected to the filter circuit module.

4. The integrated circuit for multifunctional processing of sensor signals according to claim 1, characterized in that: The filtering circuit module includes a fourth-order low-pass filter and two dual-channel operational amplifiers connected in sequence, wherein the two dual-channel operational amplifiers are each connected in series with a resistor and then in parallel with a capacitor, a capacitor is connected between each dual-channel operational amplifier and the series resistor and is grounded, and the two dual-channel operational amplifiers are also connected via a resistor; the input end of the dual-channel operational amplifier close to the input end of the filtering circuit module is also connected in series with two resistors, a capacitor is connected between the two resistors and is grounded; the output of the fourth-order low-pass filter is connected to the output end Fillter_out_0.

5. The integrated circuit for multifunctional processing of sensor signals according to claim 1, characterized in that: The range detection circuit module includes a common operational amplifier and two dual-path comparators respectively connected to the common operational amplifier, wherein the positive input end of the common operational amplifier is connected to the output end of the filter circuit module, and the negative input end is connected to the output end.

6. The integrated circuit for multifunctional processing of sensor signals according to claim 5, characterized in that: The two dual comparators, the negative input terminal of the dual comparator one is connected to the positive input terminal of the dual comparator two, the positive input terminal of the dual comparator one is connected to a positive voltage input, and the negative input output terminal of the dual comparator two is also connected to a negative voltage input; the output terminals of the two dual comparators are respectively connected to two pull-up resistors, and a resistor and a transistor are connected between each group of the two pull-up resistors.

7. The integrated circuit for multifunctional processing of sensor signals according to claim 1, characterized in that: The input end of the open circuit and short circuit detection circuit module is connected to the positive input of the sensor signal; the open circuit and short circuit detection circuit module includes two parallel dual comparators, the negative input end of the dual comparator one and the positive input end of the dual comparator two are connected to the positive input of the sensor signal, the positive input end of the dual comparator one is connected to an external voltage, and is connected to the negative input end of the dual comparator two and then grounded.

8. The integrated circuit for multifunctional processing of sensor signals according to claim 7, characterized in that: The output ends of the dual comparator 1 and the dual comparator 2 of the open circuit and short circuit detection circuit module are both connected to two pull-up resistors, and a transistor is connected between each group of the two pull-up resistors. The output of the dual comparator 1 is connected to the output end OPEN_REE, and the output of the dual comparator 2 is connected to the output end SHORT_ERR.

9. The integrated circuit for multifunctional processing of sensor signals according to claim 1, characterized in that: The input end of the excitation current circuit module is connected to the positive input of the sensor signal, and the input end is connected to the current emitter of the excitation current circuit module through a parallel transistor and a field effect transistor. The VIN pin of the current emitter is connected to the VOUT output pin of the DAC chip, and the SCKL pin and SDA pin of the DAC chip are respectively connected to an external pull-up resistor.

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