Circuit layout with diagnostic function for ASICs and procedure for ASIC diagnosis

Abstract

The present invention relates to a circuit arrangement with a diagnostic function, particularly for use in position measuring devices, comprising a higher-level ASIC (15) with an electronic circuit (14) for performing a defined function and at least one lower-level ASIC (25, 35, 45, 225, 325) with an electronic circuit (24, 34, 44, 224, 324) for performing a defined function, wherein at least one lower-level ASIC (25, 35, 45, 225, 325) comprises a parameter measuring unit (28, 38, 48, 228, 328) and the higher-level ASIC (15) comprises a diagnostic unit (16), which are interconnected via a data transmission channel (50).The parameter measurement unit (28, 38, 48, 228, 328) is designed to determine various functional parameters (Fn1, Fn2, Fn3, Fn4, Fn5) of the electronic circuit (24, 34, 44, 224, 324) of the subordinate ASIC (25, 35, 45, 225, 325) and transmit them via the data transmission channel (50) to the diagnostic unit (16). The diagnostic unit (16) is designed to determine the operability of the electronic circuit (24, 34, 44, 224, 324) of the corresponding subordinate ASIC (25, 35, 45, 225, 325) by evaluating the functional parameters (Fn1, Fn2, Fn3, Fn4, Fn5). The invention also relates to a corresponding method and a position measuring device.

Description

AREA OF TECHNOLOGY

[0001] The present invention relates to a circuit arrangement for ASICs according to claim 1 and a method for diagnosing ASICs according to claim 8. The invention further relates to a position measuring device according to claim 15. STATE OF THE ART

[0002] With the increasing digitalization of automation technology, driven by Industry 4.0, the complexity of automation measuring devices, such as rotary encoders and linear encoders, is also rising. To minimize the space requirements of the resulting extensive electronic circuits, there is a trend towards integrating more and more functional groups of these circuits into application-specific integrated circuits (ASICs).

[0003] German patent DE 10 2008 051 083 A1 describes a gear-based multiturn rotary encoder with a single-turn stage and a single-turn scanning unit for measuring the angular position of a shaft, and a plurality of multiturn stages, each with a multiturn scanning unit, for determining the number of revolutions the shaft has completed. Both the single-turn scanning unit and each multiturn scanning unit can include an ASIC.

[0004] Another requirement of Industry 4.0 is the ability of measuring devices to independently determine their operational readiness. For this reason, ASICs are frequently equipped with self-diagnostic functions. These functions are based on measuring the functional parameters of the integrated electronic circuit and evaluating the results. The evaluation results are then output by each individual ASIC in the circuit to a central location, where the operational readiness of the entire circuit is determined. However, implementing the self-diagnostic functions of the ASICs requires significant additional circuitry, leading to even greater complexity in these components.

[0005] Adaptive MEMS devices are known from US patent 2022 / 162061 A1. SUMMARY OF THE INVENTION

[0006] It is an object of the present invention to create an improved circuit arrangement for determining the operational readiness of a circuit with a plurality of ASICs.

[0007] This problem is solved by a circuit arrangement, in particular for use in position measuring devices, according to claim 1.

[0008] The circuit arrangement comprises a higher-level ASIC with an electronic circuit for performing a defined function and at least one lower-level ASIC with an electronic circuit for performing a defined function, wherein the at least one lower-level ASIC comprises a parameter measurement unit and the higher-level ASIC comprises a diagnostic unit, which are connected to each other via a data transmission channel, and wherein the parameter measurement unit is configured to determine a plurality of functional parameters of the electronic circuit of the lower-level ASIC and to transmit them to the diagnostic unit via the data transmission channel, and the diagnostic unit is configured to determine the operational readiness of the electronic circuit of the respective lower-level ASIC by evaluating the functional parameters.

[0009] Furthermore, it is an object of the present invention to create an improved method for determining the operational readiness of a circuit with a plurality of ASICs.

[0010] This problem is solved by a method for operating a circuit arrangement, in particular for use in position measuring devices, according to claim 8.

[0011] The circuit arrangement underlying the method comprises a higher-level ASIC with an electronic circuit for performing a defined function and at least one lower-level ASIC with an electronic circuit for performing a defined function, wherein the at least one lower-level ASIC comprises a parameter measurement unit and the higher-level ASIC comprises a diagnostic unit, which are interconnected via a data transmission channel. According to the proposed method, the parameter measurement unit determines a plurality of functional parameters of the electronic circuit of the lower-level ASIC and transmits them to the diagnostic unit via the data transmission channel. The diagnostic unit then determines the operational readiness of the electronic circuit of the respective lower-level ASIC by evaluating the functional parameters.

[0012] Another object of the present invention is to create a position measuring device with an improved possibility for determining operational readiness.

[0013] This problem is solved by a position measuring device according to claim 15.

[0014] Further advantages of the present invention will become apparent from the claims dependent on independent claims 1 and 8, as well as from the following description of exemplary embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] It shows Figure 1 shows a first embodiment of a circuit arrangement according to the invention in conjunction with a multiturn rotary encoder, Figure 2 shows a flowchart of a method according to the invention, Figure 3 shows a block diagram of a parameter measuring unit according to the invention, Figure 4 shows a block diagram of a diagnostic unit according to the invention, Figure 5 shows a second embodiment of a circuit arrangement according to the invention in conjunction with a multiturn rotary encoder, and Figure 6 shows a third embodiment of a circuit arrangement according to the invention in conjunction with a singleturn rotary encoder with additional sensors. DESCRIPTION THE FORMS OF EXECUTION

[0016] In the following description of advantageous embodiments, the reference numerals of components whose function has already been described with reference to a figure remain unchanged in subsequent figures. Dashed lines indicate advantageous variants of an embodiment that are mentioned in the description.

[0017] Figure 1 Figure 1 shows a first embodiment of a circuit arrangement according to the invention in conjunction with a multiturn rotary encoder. The multiturn rotary encoder essentially comprises a single-turn measuring arrangement for measuring a position value indicating the angular position of a shaft W and a multiturn measuring arrangement for counting the revolutions traveled by the shaft W.

[0018] The single-turn measuring arrangement consists of a single-turn code disk 10, the center point M of which is rotationally fixed to the shaft to be measured and carries an annular code track 11 arranged concentrically to the center point M. Furthermore, a single-turn position sensor 12 is provided for reading the code track 11 and determining the absolute position value according to the angular position of the single-turn code disk 10. If an optical scanning principle is used for position detection, the code track 11 consists, for example, of a line pattern of areas with different optical properties, such as transparent / opaque or reflective / non-reflective. Light from a light source is emitted in the direction of the code track 11, modulated by it, and finally strikes photodetectors, which are advantageously arranged in the single-turn position sensor 12.For the sake of clarity, the illustration of a light source has been omitted here. Code track 11 can be absolutely coded and / or incrementally coded and may consist of several adjacent division tracks.

[0019] Alternatively, instead of the optical scanning principle, an inductive, magnetic or capacitive scanning principle can also be used.

[0020] The multiturn measuring arrangement is used to measure rotational data suitable for determining the number of revolutions completed by the shaft W. In the example shown, it comprises three multiturn stages. Each of these multiturn stages includes a multiturn code disk 20, 30, 40, each with a code element 21, 31, 41, and a multiturn position sensor 22, 32, 42 for measuring the angular position of the code elements 21, 31, 41. The multiturn code disks 20, 30, 40 are driven by the shaft W to be measured via a three-stage reduction gear 23, 33, 43. As the shaft W rotates, the first multiturn code disk 20, driven by the first gear stage 23, has the highest rotational speed, and the third multiturn code disk 40, driven by the third and final gear stage 43, has the lowest rotational speed. The reduction ratio of gear stages 23, 33, 43 is, for example, 16:1, i.e.Sixteen revolutions of the input shaft of each gear stage 23, 33, 43 result in one revolution of the output shaft.

[0021] A magnetic scanning principle is frequently used to implement the multiturn stages. In this case, the code elements 21, 31, 41 consist of disc-shaped permanent magnets that are rotationally fixed to the multiturn code disks 20, 30, 40 and each has a dipole, i.e., a magnetic north pole N and a south pole S. The dipoles are scanned to determine the angular position of the code elements 21, 31, 41 by means of magnetic sensors (e.g., Hall sensors, MR sensors, etc.) arranged in the respective multiturn position sensors 22, 32, 42. The resolution of the multiturn position sensors 22, 32, 42 is, for example, 8 bits, meaning that one revolution of the multiturn code disks 20, 30, 40 is resolved with 256 absolute position values ​​and provided in the form of data words. By combining the data words, the number of revolutions completed by shaft W can be determined.

[0022] Alternatively, instead of the magnetic scanning principle, an inductive, optical or capacitive scanning principle can also be used.

[0023] The combination of the position values ​​of the single-turn measuring arrangement and the data words of the multi-turn stages into a total position value, which includes both the angular position of the shaft W and the number of revolutions traveled by the shaft W, takes place in the single-turn position sensor 12.

[0024] Furthermore, the single-turn position sensor 12 is designed for communication with a follower electronics unit 80 via an external data transmission channel 52. The communication includes, for example, the output of the total position value to the follower electronics unit 80.

[0025] A key component of the single-turn position sensor 12 is an application-specific integrated circuit (ASIC) in which an electronic circuit 14 integrates a number of essential functional blocks of the single-turn position sensor 12. Examples include the photodetectors, evaluation electronics, an output interface, an internal interface, and a combination unit. The electronic circuit 14 is used to execute the intended functions of the ASIC. In this embodiment, this ASIC is referred to as the higher-level ASIC 15.

[0026] In this embodiment, the intended functions of the higher-level ASIC 15 are, for example, Determination of absolute position values, determination of the total position value and communication with the downstream electronics 80.

[0027] Each multiturn position sensor 22, 32, 42 essentially consists of an application-specific integrated circuit (ASIC) in which an electronic circuit 24, 34, 44 integrates a plurality of essential functional blocks of the respective multiturn position sensor 22, 32, 42. In this example, these can be the magnetic sensors, evaluation electronics, and an output interface. This electronic circuit 24, 34, 44 serves to execute the intended functions of the ASIC. Within the scope of this embodiment, these ASICs are referred to as subordinate ASICs 25, 35, 45.

[0028] In this embodiment, one intended function of the subordinate ASICs 25, 35, 45 is to determine the data words that specify the absolute angular position of the respective multiturn code disks 20, 30, 40.

[0029] The higher-level ASIC 15 is connected to the lower-level ASICs 25, 35, and 45 for communication via at least one data transmission channel 50. Any interface connection that enables bidirectional transmission of digital data can be used as the data transmission channel 50. Both point-to-point and bus interfaces are suitable. Serial or parallel data transmission can be used. In a preferred embodiment, the data transmission channel 50 is formed by a bidirectional serial interface, in particular an I2C interface.

[0030] According to the invention, the higher-level ASIC 15 has a diagnostic unit 16 and each lower-level ASIC 25, 35, 45 has a parameter measurement unit 28, 38, 48. The diagnostic unit 16 is configured for communication with the parameter measurement units 28, 38, 48 via the data transmission channel 50.

[0031] Advantageously, communication between the electronic circuit 14 of the higher-level ASIC 15 and the electronic circuits 24, 34, 44 of the lower-level ASICs 25, 35, 45 also takes place via the data transmission channel 50, so that only one interface connection needs to be provided for the entire communication between the higher-level ASIC 15 and the lower-level ASICs 25, 35, 45.

[0032] Each parameter measurement unit 28, 38, 48 is suitably designed to determine a plurality of functional parameters Fn1, Fn2, Fn3 of the respective subordinate ASICs 25, 35, 45, in particular by measurement. Functional parameters are parameters that allow conclusions to be drawn about the proper functioning of the electronic circuit 24, 34, 44 of the subordinate ASICs 25, 35, 45, for example. Voltage values ​​at defined measuring points of the electronic circuit 24, 34, 44 of the subordinate ASIC 25, 35, 45, the current consumption of sub-circuits and / or the entire electronic circuit 24, 34, 44 of the subordinate ASIC 25, 35, 45, resistance values, characteristics of digital signals such as edge spacing, frequency, duty cycle, jitter, etc., processing time of sub-circuits of the electronic circuit 24, 34, 44 of the subordinate ASIC 25, 35, 45.

[0033] For determining the functional parameters Fn1, Fn2, Fn3, the parameter measurement unit 28, 38, 48 comprises suitable measuring instruments, for example, A / D converters, timers (especially counters), and comparators. Furthermore, the parameter measurement unit 28, 38, 48 may include signal generators, for example, current and / or voltage sources, clock generators, and D / A converters. Likewise, the parameter measurement unit 28, 38, 48 may include switching devices to connect the measuring instruments and / or the signal generators to nodes of the electronic circuit 24, 34, 44 of the subordinate ASIC 25, 35, 45. The measuring instruments, signal generators and switching devices can be exclusively assigned to the parameter measuring unit 28, 38, 48, or at least partially, only for the purpose of carrying out the self-test function of the parameter measuring unit 28, 38, 48 and otherwise serve to execute the intended function of the subordinate ASICs 25, 35, 45.In the latter case, these are sub-circuits of the electronic circuit 24, 34, 44.

[0034] The determination of the function parameters Fn1, Fn2, Fn3 is advantageously started after receiving a self-test start command ST, which arrives at the subordinate ASICs 25, 35, 45 via data transmission channel 50.

[0035] The determined function parameters Fn1, Fn2, Fn3 can be transmitted to the higher-level ASIC 15 via data transmission channel 50. Advantageously, the transmission does not occur immediately after the determination, but rather a memory is provided in the parameter measurement units 28, 38, 48 in which the function parameters Fn1, Fn2, Fn3 can be stored. The transmission then occurs as a result of receiving a data request command RD1, RD2, RD3, which is sent from the higher-level ASIC 15 via the data transmission channel to the respective lower-level ASIC 25, 35, 45.

[0036] The point in time at which the determined function parameters Fn1, Fn2, Fn3 are available in the respective subordinate ASICs 25, 35, 45 can, in the simplest case, be determined by waiting a defined period of time. Alternatively, special commands can be provided by which the superior ASIC 15 can request the status of the determination of the function parameters Fn1, Fn2, Fn3 from the subordinate ASICs 25, 35, 45 via data transmission channel 50 ("polling"). As a further alternative, the subordinate ASICs 25, 35, 45 can indicate that the function parameters Fn1, Fn2, Fn3 are available by sending a completion message via data transmission channel 50.

[0037] The functional parameters Fn1, Fn2, and Fn3 of the higher-level ASIC 15 can be supplied to the diagnostic unit 16, which is designed to assess the operational readiness of the respective subordinate ASICs 25, 35, and 45 by evaluating these parameters. The evaluation can include checking whether individual functional parameters, and / or interdependent functional parameters, are within predefined limits. If the evaluation shows that each of the subordinate ASICs 25, 35, and 45 is operational, normal operation is initiated; otherwise, fault operation occurs.

[0038] In a manner known per se, the higher-level ASIC 15 can also include a parameter measurement unit 18. This unit serves to determine internal functional parameters of the higher-level ASIC 15, which, equivalent to the functional parameters Fn1, Fn2, Fn3 of the lower-level ASICs 25, 35, 45, are evaluated in a diagnostic unit. In this case, the higher-level ASIC 15 has a self-diagnostic function. The diagnostic unit can be the diagnostic unit 16, in which the functional parameters Fn1, Fn2, Fn3 of the lower-level ASICs 25, 35, 45 are also evaluated. However, the higher-level ASIC 15 can also include an additional diagnostic unit for this purpose.

[0039] The result of the evaluation of the function parameters Fn1, Fn2, Fn3 of the subordinate ASICs 25, 35, 45 and, if applicable, the superior ASIC 15, is stored in a status information STAT. This can be output to the subsequent electronics 80 via the external data transmission channel 52, thus indicating the operational readiness of the multiturn rotary encoder.

[0040] The follower electronics 80 are an external, independent device that is spatially separated from the multiturn rotary encoder of this embodiment. For example, it is a numerical control for machine tools or another control unit for automation technology. The follower electronics 80 are not part of the present invention.

[0041] Figure 2Figure 1 shows a flowchart of a method according to the invention. The method can be performed at any time during the operation of the multiturn rotary encoder. Advantageously, it is performed immediately after switching on the device to determine its operational readiness. If necessary, ASICs 15, 25, 35, and 45 are initialized before starting the method.

[0042] In step S100, the higher-level ASIC 15 sends a self-test start command ST to at least one lower-level ASIC 25, 35, 45. Depending on the test strategy, it may be advantageous to send the self-test start command ST to only one of the lower-level ASICs 25, 35, 45, namely when the operational readiness of this one lower-level ASIC 25, 35, 45 is to be specifically determined. Preferably, however, the self-test start command ST is sent to all lower-level ASICs 25, 35, 45 configured according to the invention, so that the operational readiness of all lower-level ASICs 25, 35, 45 can be determined virtually simultaneously.

[0043] In step S110, the subordinate ASICs 25, 35, and 45 that have received the self-test start command ST determine the majority of function parameters Fn1, Fn2, and Fn3 necessary to establish operational readiness. The superior ASIC 15 waits until the determination of the function parameters Fn1, Fn2, and Fn3 is complete. As described above, this can be achieved by waiting a defined period of time, by querying the status of the determination of the function parameters Fn1, Fn2, and Fn3, or by waiting for a completion message from the subordinate ASICs 25, 35, and 45.

[0044] In step S120, the function parameters Fn1, Fn2, Fn3 are transmitted via data transmission channel 50 to the higher-level ASIC 15, in particular to the diagnostic unit 16. The transmission can be started by sending data request commands RD1, RD2, RD3 to the respective subordinate ASICs 25, 35, 45.

[0045] In step S130, the diagnostic unit 16 evaluates the functional parameters Fn1, Fn2, Fn3 and assesses the operational readiness of the respective subordinate ASICs 25, 35, 45. The result of the evaluation is stored in a status information STAT.

[0046] In step S140, a decision is made based on the status information STAT as to whether normal operation can be initiated (step S150A) or whether fault operation can be initiated (step S150B).

[0047] Figure 3 Figure 1 shows a block diagram of a parameter measuring unit according to the invention. It is based on the parameter measuring unit 28 of the Figure 1 As described, the parameter measurement units 28, 38, 48 are advantageously constructed identically.

[0048] The parameter measurement unit 28 comprises a sequence control 280, measuring instrument 281, a memory 282 and an interface unit 283. It can also include at least one signal generator 284.

[0049] The sequence controller 280 controls the execution of the self-test function. It is advantageously designed as a digital state machine. The sequence controller 280 controls the measuring instruments 281, the signal generator 284, and, if applicable, the memory 282 according to the commands supplied to it by the higher-level ASIC 15 via the signal transmission channel 50 and the interface unit 283. It is also designed to indicate to the higher-level ASIC 15, via the interface unit 283 and the data transmission channel 50, the completion of the self-test function or the availability of the function parameter Fn1.

[0050] The measuring instruments 281 are used to measure the functional parameters Fn1. For this purpose, they are connected to at least one measuring point MPx of the electronic circuit 24 of the subordinate ASIC 25. The measuring instruments 281 can include an A / D converter, a timing unit, or a comparator for performing the measurements. Furthermore, the measuring instruments 281 can include switching elements to connect a plurality of measuring points MPx to the units performing the measurements for the duration of the measurement.

[0051] The functional parameters Fn1 measured by the measuring instruments 281 can be stored in the memory 282 and transferred from the interface unit 283 to the higher-level ASIC 15 via the data transmission channel 50.

[0052] The signal generator 284 is configured to generate at least one electrical signal and feed it into at least one input point EPx of the electronic circuit 24 of the subordinate ASIC 25. Signal generators 284 can include signal-generating units such as voltage sources, D / A converters, and clock generators. Examples of electrical signals are constant voltages and / or currents, alternating voltages of any waveform such as sinusoidal voltages, square waves, etc. The signal generator 284 can also include switching elements to connect a plurality of input points EPx to the signal-generating unit in the signal generator 284 for the duration of the measurement of a function parameter Fn1.

[0053] The communication unit 283 serves to communicate between the parameter measurement unit 28 and the higher-level ASIC 15 via the data transmission channel 50. The communication is bidirectional, so that commands and / or data can be received from the higher-level ASIC 15, and data, in particular function parameter Fn1, can be transmitted to the higher-level ASIC 15.

[0054] As shown by the dashed line, it is particularly advantageous if the communication between the electronic circuit 24 of the subordinate ASIC 25 and the electronic circuit 14 of the superior ASIC 15 also takes place via the interface unit 283. In this way, only a single interface connection between the subordinate ASIC 25 and the superior ASIC 15 is required for self-test operation and normal operation of the ASICs.

[0055] Figure 4Figure 1 shows a block diagram of a diagnostic unit 16 according to the invention. It comprises a diagnostic controller 160, an interface unit 162, and a device interface 163. The diagnostic unit 16 can also include a memory 161.

[0056] The diagnostic controller 160 manages the self-test function. To do this, it initiates the determination of the function parameters Fn1, Fn2, Fn3 in the parameter measurement units 28, 38, 48 of the subordinate ASICs 25, 35, 45 by sending the self-test start command ST and initiates the transmission of the function parameters Fn1, Fn2, Fn3 by sending data request commands RD1, RD2, RD3. The transmission of the commands and data takes place via the interface unit 162, the data transmission channel 50, and the interface unit 283 of the self-test unit 28, 38, 48 to be addressed.

[0057] The diagnostic controller 160 is designed to check the functional parameters Fn1, Fn2, Fn3 received from the subordinate ASICs 25, 35, 45 for compliance with limit values. This allows the controller to assess the operational readiness of the subordinate ASICs 25, 35, 45 and to decide whether to switch to normal operation or fault mode. The limit values ​​can include upper and / or lower limits of individual functional parameters, as well as dependencies between two or more of the functional parameters. Examples of such dependencies are the ratio of input to output signals of amplifier circuits, or the dependence of instantaneous values ​​on signals that are phase-shifted relative to each other, particularly on sinusoidal sensor signals that are phase-shifted by 90° and frequently encountered in position measurement technology.

[0058] The result of the test can be stored in a status information STAT and output to the subsequent electronics 80 via the device interface 163 and the external data transmission channel 52.

[0059] As shown by the dashed lines and described above using the interface unit 283 of the subordinate ASIC 25, it is particularly advantageous if the communication between the electronic circuit 14 of the superior ASIC 15 and the electronic circuit 24, 34, 44 of the respective subordinate ASIC 25, 35, 45 also takes place via the interface unit 162.

[0060] Likewise, it is advantageous if the device interface 163 is designed in such a way that it allows not only communication between the diagnostic unit 16, but also communication between the electronic circuit 14 of the higher-level ASIC 15 and the subsequent electronics 80.

[0061] Memory 161 can be used to store the function parameters Fn1, Fn2, Fn3 before they are evaluated by the diagnostic control unit 160. Furthermore, it can be provided that the function parameters Fn1, Fn2, Fn3 can be transferred from memory 161 to the subsequent electronics unit 80, enabling further analysis of a fault condition there.

[0062] In a further advantageous embodiment, the memory 161 can be used to store the limit values ​​and, if applicable, further rules for evaluating the function parameters Fn1, Fn2, Fn3 in the diagnostic controller 160. If the memory 161 is also writable, the diagnostic unit 16 can be adapted to various subordinate ASICs and the self-test can be performed.

[0063] Another advantageous feature is that the memory 282 of the subordinate ASICs can be written to and / or erased by the diagnostic unit 15 via data transmission channel 50. This makes it possible to verify the function of the memory 282.

[0064] Figure 5 Figure 1 shows a second embodiment of a circuit arrangement according to the invention in conjunction with a multiturn rotary encoder. In contrast to the first embodiment, the multiturn measuring arrangement of the multiturn rotary encoder does not have a gear-based revolution counter, but rather an electronic revolution counter.

[0065] The single-turn measuring arrangement corresponds to the one from Figure 1 , whereby it is pointed out that the electronic circuit 14 of the higher-level ASIC 15 differs from the Figure 1 can distinguish.

[0066] The multiturn measuring arrangement comprises a multiturn code disk 200 with a code element 210, and a multiturn position sensor 220 for measuring the number of revolutions traveled by the shaft W by measuring and evaluating the angular position of the code element 210, which is rotationally fixed to the shaft W. Thus, the measuring principle is equivalent to that of a multiturn stage of the multiturn rotary encoder. Figure 1 .

[0067] The multiturn position sensor 220 essentially consists of an ASIC 225 in which an electronic circuit 224 is integrated. This circuit serves to perform the intended functions, in particular to determine the number of revolutions traveled by the shaft W (revolution data) and to transmit this data via the data transmission channel 50 to the singleturn position sensor 12. The ASIC is thus a subordinate ASIC 225 according to the invention.

[0068] To enable measurement of the number of revolutions even when the multiturn encoder is switched off, a battery can be provided in the multiturn position sensor 220, which supplies power to at least those parts of the electronic circuit 224 required for revolution counting. Alternatively, instead of using a battery, the multiturn position sensor 220 can be implemented using the principle of energy harvesting, for example, by using a Wiegand wire.

[0069] The subordinate ASIC 225 now has a parameter measurement unit 228, which is suitable for determining a plurality of function parameters Fn4 and transmitting them via the data transmission channel 50 to the diagnostic unit 16 in the superior ASIC 15. For this purpose, the parameter measurement unit 228 can be used analogously to the one based on the Figure 3 The described parameter measurement unit must be constructed.

[0070] Figure 6Figure 1 shows a third embodiment of a circuit arrangement according to the invention in conjunction with a single-turn rotary encoder with additional sensors. Additional sensors are used when a measuring device, in addition to its primary measurement task—for example, in automation technology, measuring the angular position and / or the number of revolutions of a shaft W, or measuring linear movements of a machine part—is also required to measure additional parameters inside and / or outside the measuring device. Prominent examples of such parameters are temperature, accelerations, vibrations, and humidity.

[0071] The single-turn measuring arrangement corresponds to the one from Figure 1 , whereby it is pointed out that the electronic circuit 14 of the higher-level ASIC 15 differs from the Figure 1 can be distinguished because they have different intended functions.

[0072] A sensor data recorder 320 is provided for recording measured values ​​from at least one additional sensor, to which at least one, but preferably a plurality of additional sensors 330, 331, 332 can be connected.

[0073] The sensor data transducer 320 essentially consists of an ASIC 325 in which an electronic circuit 324 is integrated. This circuit serves to perform the intended functions of the ASIC, in particular the querying and, if necessary, processing of measurement data from the auxiliary sensors 330, 331, 332 and their transmission via the data transmission channel 50 to the single-turn position transducer 12. The ASIC is thus a subordinate ASIC 325 according to the invention.

[0074] The subordinate ASIC 325 also features a parameter measurement unit 328, which is designed to determine a plurality of function parameters Fn5 and transmit them via data transmission channel 50 to the diagnostic unit 16 in the superior ASIC 15. For this purpose, the parameter measurement unit 328 can be used analogously to the one based on the Figure 3 The described parameter measurement unit 28 is constructed as follows:

[0075] It should be noted that even those based on the Figure 1 and 5 The described embodiments can be supplemented by a sensor data transducer 320. This means that the present invention is also suitable for circuit arrangements comprising a plurality of different subordinate ASICs.

[0076] Therefore, it is particularly advantageous if the higher-level ASIC 15, in particular its electronic circuit 14, is designed in such a way that it can be used in several device variants and in conjunction with different lower-level ASICs, for example in the embodiments of the Figure 1 , 5 and 6 , as well as combinations thereof.

[0077] Of course, the present invention is not limited to the described embodiments, but can be suitably modified by a person skilled in the art within the scope of protection of the patent claims.

Claims

1. Circuit arrangement, in particular for use in position measuring devices, comprising • a superordinate ASIC (15) with an electronic circuit (14) for performing an intended function and • at least one subordinate ASIC (25, 35, 45, 225, 325) with an electronic circuit (24, 34, 44, 224, 324) for performing an intended function, wherein the at least one subordinate ASIC (25, 35, 45, 225, 325) comprises a parameter measuring unit (28, 38, 48, 228, 328) and the superordinate ASIC (15) comprises a diagnostic unit (16), which are connected to one another via a data transmission channel (50), and wherein • the parameter measuring unit (28, 38, 48, 228, 328) is designed to ascertain a plurality of functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) of the electronic circuit (24, 34, 44, 224, 324) of the subordinate ASIC (25, 35, 45, 225, 325) and to transmit them to the diagnostic unit (16) via the data transmission channel (50) and • the diagnostic unit (16) is designed to determine the functional readiness of the electronic circuit (24, 34, 44, 224, 324) of the respective subordinate ASIC (25, 35, 45, 225, 325) by evaluating the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5).

2. Circuit arrangement according to Claim 1, wherein the parameter measuring unit (28, 38, 48, 228, 328) comprises a sequence controller (280) for controlling the sequence of the self-test function, measuring means (281) for ascertaining the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) by measuring at at least one measuring point (MPx) of the electronic circuit (24, 34, 44, 224, 324) and an interface unit (283) for communicating with the superordinate ASIC (15) over the data transmission channel (50).

3. Circuit arrangement according to either of the preceding claims, wherein the parameter measuring unit (28, 38, 48, 228, 328) comprises a memory (282) in which the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) are able to be stored.

4. Circuit arrangement according to Claim 3, wherein the diagnostic unit (15) is able to write to and / or delete from the memory (282).

5. Circuit arrangement according to one of the preceding claims, wherein the parameter measuring unit (28, 38, 48, 228, 328) comprises at least one signal generator (284) for generating at least one electrical signal and for feeding it into at least one feed-in point (EPx) of the electronic circuit (24, 34, 44, 224, 324).

6. Circuit arrangement according to one of the preceding claims, wherein the diagnostic unit (16) comprises a diagnostic controller (160) for controlling the sequence of the self-test function, an interface unit (162) for communicating with the respective parameter measuring units (28, 38, 48, 228, 328) over the data transmission channel (50), and a device interface (163) for communicating with downstream electronics (80) over an external data transmission channel (52).

7. Circuit arrangement according to one of the preceding claims, wherein the diagnostic unit (16) comprises a memory (161) in which the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) and / or limit values for the evaluation of the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) and / or further rules for the evaluation of the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) are able to be stored.

8. Method for operating a circuit arrangement, in particular for use in position measuring devices, comprising • a superordinate ASIC (15) with an electronic circuit (14) for performing an intended function and • at least one subordinate ASIC (25, 35, 45, 225, 325) with an electronic circuit (24, 34, 44, 224, 324) for performing an intended function, wherein the at least one subordinate ASIC (25, 35, 45, 225, 325) comprises a parameter measuring unit (28, 38, 48, 228, 328) and the superordinate ASIC (15) comprises a diagnostic unit (16), which are connected to one another via a data transmission channel (50), comprising the following steps: • ascertaining a plurality of functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) of the electronic circuit (24, 34, 44, 224, 324) of the subordinate ASIC (25, 35, 45, 225, 325) and transmitting the plurality of functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) to the diagnostic unit (16) via the data transmission channel (50) by way of the parameter measuring unit (28, 38, 48, 228, 328) and • determining the functional readiness of the electronic circuit (24, 34, 44, 224, 324) of the respective subordinate ASIC (25, 35, 45, 225, 325) by evaluating the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) in the diagnostic unit (16).

9. Method according to Claim 8, wherein the parameter measuring unit (28, 38, 48, 228, 328) comprises a sequence controller (280), measuring means (281) and an interface unit (283), wherein • the sequence of the self-test function is controlled by the sequence controller (280), • the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) are ascertained at at least one measuring point (MPx) of the electronic circuit (24, 34, 44, 224, 324) by way of measurement by the measuring means (281) and • communication is made with the superordinate ASIC (15) over the data transmission channel (50) via the interface unit (283).

10. Method according to either of Claims 8 and 9, wherein the parameter measuring unit (28, 38, 48, 228, 328) comprises a memory (282) in which the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) are stored.

11. Method according to Claim 10, wherein the diagnostic unit (15) writes to and / or deletes from the memory (282).

12. Method according to one of Claims 8 to 11, wherein the parameter measuring unit (28, 38, 48, 228, 328) comprises at least one signal generator (284) that generates at least one electrical signal and feeds it into at least one feed-in point (EPx) of the electronic circuit (24, 34, 44, 224, 324).

13. Method according to one of Claims 8 to 12, wherein the diagnostic unit (16) comprises a diagnostic controller (160), an interface unit (162), and a device interface (163), wherein • the sequence of the self-test function is controlled by the diagnostic controller (160), • communication is made with the respective parameter measuring units (28, 38, 48, 228, 328) over the data transmission channel (50) via the interface unit (162) and • communication is made with downstream electronics (80) over an external data transmission channel (52) via the device interface (163).

14. Method according to one of Claims 8 to 13, wherein the diagnostic unit (16) comprises a memory (161) in which the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) and / or limit values for the evaluation of the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) and / or further rules for the evaluation of the functional parameters (Fnl, Fn2, Fn3, Fn4, Fn5) are stored.

15. Position measuring device, comprising a circuit arrangement according to one of Claims 1 to 7.

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