Application specific integrated circuit for measuring equipment

Abstract

An application-specific integrated circuit for a measurement device, comprising: a first finite-state machine configured to control an external radar chip configured to generate and / or detect a radar measurement signal; and a second finite state machine configured to monitor a memory or processor and / or to monitor an external radar chip, the memory or processor configured to determine a measurement value from a radar measurement signal detected by the external radar chip.

Description

[0001] Citation of Related Applications

[0002] This application claims the priority of German patent application 10 2023 200 484.4 filed on January 23, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to measuring device technology for process automation in industrial or private environments. In particular, the present invention relates to an application-specific integrated circuit, ie, an ASIC, for a measuring device, a measuring device having an application-specific integrated circuit, and the use of an ASIC for a measuring device. Technical Background

[0004] Measuring devices used for process automation in industrial or private settings can include radar circuitry for generating and emitting high-frequency radar measurement signals. These radar measurement signals are reflected, for example, by the surface of a filler material or an object to be detected and captured by the measuring device's antenna. This signal can be used to calculate the distance to the filler material surface or the object.

[0005] Examples of such measuring devices include radar level measuring devices that can be installed in the container. These radar level measuring devices can be free-radiating or use the guided microwave principle. In the case of the guided microwave principle, an elongated measuring probe is provided that is immersed in the filling material.

[0006] Such measuring devices often have a very limited power supply, for example in the form of a 4 to 20 mA two-wire cable or, particularly in the case of self-contained measuring devices, a battery. To reduce the power consumption of such measuring devices, the measuring frequency can be reduced. However, level changes during the measurement pauses can only be recorded at a later time. Summary of the Invention

[0007] The object of the present invention is to provide a radar measuring device which is distinguished by energy-saving operation and high measuring accuracy.

[0008] This object is achieved by the features of the independent claim. Further developments of the invention are reflected in the dependent claims and in the following description of exemplary embodiments.

[0009] A first aspect of the present disclosure relates to an application-specific integrated circuit ASIC for a measuring device, which includes a first finite state machine and a second finite state machine.

[0010] The first finite state machine is configured to control an external radar chip of the measuring device, the external radar chip being configured to generate a radar measurement signal and detect the measurement signal reflected from a surface of an object or filler material. The second finite state machine is configured to monitor a memory of the ASIC and / or the external radar chip, the memory being configured to determine a measurement value based on the radar measurement signal detected by the external radar chip. Additionally or alternatively, the second finite state machine may be configured to monitor a processor of the measuring device and / or the external radar chip, the processor being configured to determine a measurement value based on the radar measurement signal detected by the external radar chip.

[0011] The measuring device is, for example, a fill-level measuring device, in particular a fill-level radar measuring device or another radar measuring device.

[0012] The external radar chip is configured to generate a radar measurement signal, which is then transmitted via an antenna or radiating element. The processor is configured to determine a measurement value based on the received radar signal. The external radar chip and the ASIC are separate components and are interconnected via corresponding control and power supply lines. The ASIC and external radar chip can also be designed as an integrated component.

[0013] The ASIC can be implemented as a radar companion ASIC, which performs control tasks and / or measured value detection tasks in the radar circuit of a measuring device. This allows the necessary control and detection tasks to be cost-effectively integrated into a compact unit when using different radar chips, while ensuring energy-efficient operation of the corresponding radar chip.

[0014] According to one embodiment, the ASIC includes a phase-locked loop (PLL).

[0015] According to another embodiment, an ASIC includes analog-to-digital converter circuitry (ADC).

[0016] According to another embodiment, an ASIC includes a digital interface for a processor.

[0017] According to another embodiment, the first finite state machine and the second finite state machine are implemented as an integrated component.

[0018] According to another embodiment, the external radar chip is a radar MMIC (Monolithic Microwave Integrated Circuit).

[0019] According to another embodiment, the ASIC is configured to wake up the processor from a sleep mode and then transfer the measurement data to the processor.

[0020] According to another embodiment, the ASIC is configured to supply power to a voltage controlled oscillator (VCO) of the external radar chip and / or a frequency multiplier of the external radar chip.

[0021] The PLL, ADC, power management, and security functions can all be integrated on the ASIC. Specifically, the ASIC can be configured to support different radar chips with different operating frequencies, such as 6 GHz, 24 GHz, 80 GHz, 180 GHz, and 240 GHz. To this end, the finite state machine can be programmed accordingly.

[0022] Radar chips and ASICs can be optimized with respect to the energy requirements of echo curve detection. Specifically, individual components of the radar chip, ASIC, and / or processor can be powered on only when actually needed. Unnecessary circuit components can be quickly shut down. This allows the radar circuit to be optimized in terms of size and cost.

[0023] In particular, the radar circuitry of the measurement device can be configured to be powered by a limited energy source (e.g., a 4 to 20 mA power supply or an energy harvesting device). A 3.3 V supply voltage can be provided to both the processor and the ASIC. The ASIC can also be configured for multiple different supply voltages. The ASIC and radar chip can be located on the same circuit board.

[0024] The radar circuit and in particular the ASIC can be configured to operate in an energy-saving operating mode after completion of the measurement and in particular during determination of the measured value, the nature of which operating mode depends on the radar chip used.

[0025] The term "process automation in an industrial environment" can be understood as a branch of technology encompassing measures that enable machines and systems to operate without human intervention. One goal of process automation is to automate the interactions between individual plant components in the chemical, food, pharmaceutical, oil, paper, cement, shipping, or mining industries. For this purpose, various sensors are used, tailored to the specific requirements of the process industry, such as mechanical stability, tolerance to contamination, and extreme temperatures and pressures. The measured values ​​from these sensors are typically transmitted to a control room, where process parameters such as fill level, limit level, flow, pressure, or density can be monitored, and plant-wide settings can be modified manually or automatically.

[0026] Process automation in the industrial context can be understood as a branch of technology encompassing all measures for operating machines and plants without human intervention. One of the goals of process automation is to automate the interactions between the various components in plants for the chemical, food, pharmaceutical, oil, paper, cement, shipping, or mining industries. To this end, a wide range of sensors can be used, which are specifically tailored to the specific requirements of the process industry, such as mechanical stability and insensitivity to contamination, extreme temperatures, and pressures. The measured values ​​from these sensors are typically transmitted to a control room, where process parameters such as fill level, limit level, flow rate, pressure, or density can be monitored, and plant-wide settings can be modified manually or automatically.

[0027] One area of ​​process automation in industrial environments involves the automation of factory logistics and supply chain logistics. In the field of logistics automation, distance and angle sensors are used to automate processes within buildings or within individual logistics systems. Typical applications for logistics automation systems include: airport baggage and freight handling, traffic monitoring (toll collection systems), retail, parcel delivery or building security (access control). What the above examples have in common is that each application requires the combination of presence detection with the precise measurement of the size and position of an object. Sensors based on optical measurement methods using lasers, LEDs, 2D cameras or 3D cameras can be used for this purpose, which measure distances according to the time-of-flight principle (ToF).

[0028] Another area of ​​process automation within the industrial environment involves factory / manufacturing automation. Application examples can be found in a variety of industries, such as automotive manufacturing, food production, the pharmaceutical industry, and general packaging. The goal of factory automation is to automate the production of goods using machines, production lines, and / or robots—that is, to operate without human intervention. The specific requirements for sensors used here and the measurement accuracy required to detect the position and size of objects are comparable to those in the previous example of logistics automation.

[0029] The following will describe embodiments of the present disclosure with reference to the accompanying drawings. When the same reference numerals are used in the following description of the drawings, they represent the same or similar elements. The illustrations in the drawings are for schematic purposes only and are not drawn to scale.

[0030] Another aspect of the present disclosure relates to a measuring device comprising: a radar chip configured to generate and detect radar measurement signals; and an application specific integrated circuit as described above and below, which is arranged, for example, between the radar chip and a processor.

[0031] A further aspect of the present disclosure relates to the use of the application-specific integrated circuit described above and below for a measuring device, in particular for a level radar measuring device comprising a radar chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Shown is a circuit diagram of a radar MMIC with peripheral circuits using discrete components.

[0033] Figure 2 An application specific integrated circuit is shown that can perform control and detection tasks while operating as a purely analog MMIC.

[0034] Figure 3 The structure of a radar measuring device with an application-specific integrated circuit is shown.

[0035] Figure 4 The versatility of the ASIC to the radar MMIC widely used for level measurement is shown.

[0036] Figure 5 The overall process of the self-test function in the ASIC is shown.

[0037] Figure 6 Shows part of the test process for an externally connected MMIC.

[0038] Figure 7 A measuring device with a radar circuit is shown. DETAILED DESCRIPTION

[0039] Figure 1 The figure shows a radar MMIC 101, whose peripheral circuits use discrete components. This radar MMIC generates an 80 GHz radar measurement signal; an antenna 118 radiates the radar measurement signal toward the filler material. The MMIC includes a voltage-controlled oscillator (VCO) 107 controlled by an external PLL 104. Furthermore, a TCXO oscillator 115 is provided, which controls the PLL at a frequency of 40 MHz. The TCXO oscillator 115 also controls the analog-to-digital converter circuit 105.

[0040] In addition to VCO 107, the MMIC also includes a frequency multiplier 108, which is controlled by VCO 107 at 40 GHz. This frequency multiplier doubles the frequency and controls a TX amplifier 109, which is connected to an antenna 118 via a transmit / receive switch, such as a circulator. A downconverter 110 is also provided, which receives the signals from frequency multiplier 108 and the transmit / receive switch.

[0041] All other components are external to the MMIC. Downconverter 110 passes its signal to amplification and filtering circuit 113, which then passes it to ADC 105. ADC 105 is connected to the measurement device's processor 103 via an SPI interface. Processor 103 can exchange data with external memory 116. Furthermore, processor 103 is connected to a fieldbus modem 117 for transmitting measured values.

[0042] Figure 2 A radar companion (RC) ASIC 102 is shown, which can perform control tasks and detection tasks during the operation of the purely analog MMIC. The ASIC 102 includes a linearization circuit (e.g., an integer or fractional rational PLL 104), a power supply 111, a self-test circuit 112 (e.g., in the form of a second finite state machine 112), an amplification and filtering circuit 113 or an IF gain AAF circuit 113, an analog-to-digital converter circuit 104 (e.g., which is configured to convert the analog signal into a digital value with a precision of 16 bits and a sampling frequency of 40 MHz), a first-in-first-out (FIFO) memory 114, and a finite state machine (FSM) 106. The ASIC 102 is a separate component, but can be arranged on the same circuit board as the MMIC 101 (see Figure 3 ). Figure 3 The structure of a radar circuit 100 for a radar measuring device is shown. Radar circuit 100 includes the aforementioned ASIC 102. ASIC 102 is connected between radar chip 101 and processor 103. Communication between ASIC 102 and processor 103 is performed using a QSPI interface, for example, via FIFO 114. Processor 103 also communicates with FSM 106 via an SPI interface.

[0043] FSM 106 can be programmed to match the connected radar chip. The FSM may include suitable hardware components for this purpose. Specifically, the FSM can be configured by the processor to set parameters for distance measurements using the FMCW method. Depending on the operating frequency of the connected radar chip, for example due to certification requirements, FSM 106 may need to store the start frequency, stop frequency, time duration, transmit power, and / or other parameters of the respective radar chip. This allows MMIC 101 to be activated during subsequent measurements using appropriate signals, enabling it to perform the desired measurements. Specifically, the FSM fully controls the MMIC during measurement execution, eliminating the need for intervention or coordination from processor core 103. For example, to save energy, processor core 103 can be switched to a power-saving state by FSM 106 while performing radar measurements and reactivated by FSM 106 after data detection is complete.

[0044] FSM 106 may also be configured to pass information about each connected radar chip 101 to second finite state machine 112. Furthermore, second finite state machine 112 may be configured to independently identify the type of each connected MMIC 101. Second finite state machine 112 may use the information about the type of connected MMIC 101 to optimize the self-test process and perform the process appropriately for the connected MMIC.

[0045] ASIC 102 can supply power to VCO 107 and frequency multiplier 108 of MMIC 101 and perform or trigger a self-test of MMIC 101 (see Figure 3 ). In particular, the RC-ASIC 102 can be used to check the functionality of the MMIC 101. This is particularly advantageous for SIL applications. It is possible that the processor 103 is integrated into the ASIC 102. However, if Figure 3 As shown, it can also be a separate component.

[0046] In particular, MMIC 101 and RC-ASIC 102 can be manufactured using different semiconductor technologies and chip materials. Thus, the MMIC can be optimized for high-frequency applications (e.g., 80 GHz or higher), while RC-ASIC 102 can be optimized for significantly lower frequency applications (e.g., 40 MHz). This can save energy compared to integrating an ASIC module onto the MMIC.

[0047] Figure 4 The versatility of the RC-ASIC 102 for radar MMICs for level measurement, which are designed for very different frequency ranges (eg 6 GHz, 24 GHz, 80 GHz, 180 GHz and 240 GHz), is shown.

[0048] Figure 5 The overall process of the self-test function in the companion ASIC 102 is shown. The method starts at step 501. In step 502, the radar companion ASIC 102 is configured. In step 503, the safety settings are configured. In step 504, it is determined whether the time period since the last FIFO memory test is greater than a pre-set minimum time period t safe .

[0049] If not, the method continues to execute step 507. In this case, there is no need to test the FIFO memory integrated in the radar companion ASIC 102.

[0050] If the time period since the last FIFO memory test is greater than a pre-settable minimum time period t safe , then the next step is step 505, in which the FIFO memory is internally tested. Then, in step 506, the test result is provided to the outside.

[0051] In step 507, it is evaluated whether the time period since the last MMIC test is greater than a predeterminable minimum time period t MMICsafe If not, the method jumps to step 510 because no MMIC test is required. If yes, the method proceeds to step 508, where the MMIC test is performed. In step 509, the test results are provided to the outside.

[0052] Finally, in step 510 , a normal measurement of the measuring device, for example, a fill level measurement, is started. The method ends in step 511 .

[0053] Figure 6 The figure shows a portion of the process for testing an externally connected MMIC. The method begins at step 601. In step 602, a test signal in the kHz range is provided. In step 603, the measurement process in the MMIC is started. In step 604, the measurement data is read into the FIFO, and in step 605, the MMIC is deactivated. In step 606, the test signal in the FIFO data is analyzed, and in step 607, it is determined whether the test signal was correctly recorded. If not, the method jumps to step 609, where a "unreliable" or similar status is output. If so, the method jumps to step 608, where a "reliable" or similar status is output. The method then ends at step 610.

[0054] Figure 7 A measuring device 200 with the above-described circuit 100 is shown, for example a radar level measuring device, comprising a level radar antenna 118 for transmitting radar measurement signals and for receiving radar measurement signals reflected on the surface of a filling material.

[0055] The present disclosure provides a radar companion ASIC that combines the necessary control and detection tasks in a compact unit at low cost while using commercial radar chips, and is specifically configured to monitor itself and externally connected commercial MMICs according to IEC61508 to ensure reliable operation.

[0056] The PLL, ADC, power management, and safety functions can be integrated into a single chip. Specifically, the ASIC can support different radar chips with different operating frequencies and built-in self-test (BIST) capabilities. The ASIC can be configured to provide signals to indicate the safe and / or unsafe state of the entire system.

[0057] The signal provided to the outside can indicate the current safety status of the radar companion ASIC and / or the externally connected radar MMIC.

[0058] The terms used in the claims should be understood to be given their broadest reasonable interpretation consistent with the preceding description. For example, the use of the article "a" or "the" when introducing an element should not be understood to exclude multiple elements. Similarly, the word "or" should be understood to include multiple elements, so the phrase "A or B" does not exclude "A and B" unless the context or the preceding description clearly indicates that only one of A and B is meant. In addition, the phrase "at least one of A, B, and C" should be understood to refer to one or more elements in the group of elements consisting of A, B, and C, and should not be understood to require that at least one of each element listed in A, B, and C be included, regardless of whether A, B, and C belong to the same category. In addition, references to "A, B and / or C" or "at least one of A, B, or C" should be interpreted to include any single unit of the listed elements, such as A, any subset of the listed elements, such as A and B, or the entire list of elements A, B, and C.

Claims

1. An application specific integrated circuit (102) for a measuring device (200), comprising: a first finite state machine (106) configured to control an external radar chip (101), the external radar chip being configured to generate and / or detect radar measurement signals; A second finite state machine (112) is configured to monitor a memory (114) of the ASIC (102) and / or the external radar chip, wherein the memory is configured to determine a measurement value based on the radar measurement signal detected by the external radar chip (101).

2. The application specific integrated circuit (102) according to claim 1, in, The application-specific integrated circuit (102) includes a phase-locked loop (104), the application-specific integrated circuit is an ASIC, and the phase-locked loop is a PLL.

3. The application specific integrated circuit (102) according to claim 1 or 2, in, The ASIC (102) includes an analog-to-digital converter circuit (105), which is an ADC.

4. The application specific integrated circuit (102) according to any one of the preceding claims, wherein The ASIC (102) comprises a digital interface for a processor (103) of the measuring device (200).

5. An application specific integrated circuit (102) according to any one of the preceding claims, in, The first finite state machine (106) and the second finite state machine (112) are implemented as an integrated component.

6. An application specific integrated circuit (102) according to any one of the preceding claims, in, The external radar chip (101) is a radar MMIC.

7. An application specific integrated circuit (102) according to any one of the preceding claims, in, The ASIC (102) is a radar supporting ASIC that performs control tasks and / or measurement value detection tasks of the measuring device (200).

8. An application specific integrated circuit (102) according to any one of the preceding claims, in, The ASIC (102) is configured to wake up the processor (103) from sleep mode and then transfer measurement data to the processor.

9. An application specific integrated circuit (102) according to any one of the preceding claims, in, The ASIC (102) is configured to supply power to a voltage-controlled oscillator (107) of the external radar chip (101) and / or a frequency multiplier (108) of the external radar chip, wherein the voltage-controlled oscillator is a VCO.

10. A measuring device (200), comprising: a radar chip (101) configured to generate a radar measurement signal; The application specific integrated circuit (102) according to any one of claims 1 to 9, which is an ASIC.

11. The measuring device (200) according to claim 10, in, The ASIC and the radar chip are separate components.

12. The measuring device (200) according to claim 10 or 11, which is realized as a level radar measuring device (200).

13. Use of the application-specific integrated circuit (102) according to any one of claims 1 to 9 for a measuring device, in particular for a level radar measuring device (200) comprising a radar chip (101), the application-specific integrated circuit being an ASIC.

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