Sensor powered digital control loop

Abstract

The invention relates to a sensor powered digital control loop. Various examples in accordance with the present disclosure provide example methods, systems, and apparatus for a digital control loop for sensor power supply.

Description

Technical Field

[0001] Example embodiments of the present disclosure relate to sensor power supply, and more particularly to a digital control loop for sensor power supply, which is particularly applicable to Distributed System Interface (DSI3), Wheel Speed Sensor (WSS), and Peripheral Sensor Interface (PSI5) compatible systems. Background Art

[0002] The applicant has found many technical challenges and difficulties associated with sensor power supply. Through effort, ingenuity, and innovation, the applicant has solved many of these discovered problems by developing the embodiments of the present disclosure, which are described in detail below. Summary of the Invention

[0003] The various embodiments described herein relate to sensor power supply, and more particularly to a digital control loop for sensor power supply, which is particularly applicable to DSI3, WSS, and PSI5 compatible systems.

[0004] According to one aspect of the present disclosure, a digital control loop for sensor power supply is provided. In some embodiments, the digital control loop sensor includes a digital control loop for sensor power supply, the digital control loop including: an analog-to-digital module configured to receive an analog input voltage and generate a digital signal corresponding to the analog input voltage; a voltage drop module coupled to the analog-to-digital module, the voltage drop module being configured to receive one or more of a fixed voltage drop or a modulated voltage drop and generate a reference voltage control signal based on one or more of the fixed voltage drop or the modulated voltage drop; a digital-to-analog module coupled to the voltage drop module, the digital-to-analog module being configured to generate a reference voltage based on the reference voltage control signal; and a voltage regulator module coupled to the digital-to-analog module and at least one sensor, the voltage regulator module being configured to compare the reference voltage with the sensed voltage at an output node coupled to the at least one sensor and control the supply voltage of the sensor based on the comparison of the reference voltage with the sensed voltage.

[0005] In some embodiments, it may be configured to generate a reference voltage control signal by subtracting a fixed voltage drop from the digital signal corresponding to the analog input voltage, wherein the reference voltage control signal has a fixed value.

[0006] In some embodiments, the voltage drop module is configured to generate a reference voltage control signal by applying a modulated voltage drop to the digital signal during a forward communication configured to transmit a message to at least one sensor.

[0007] In some embodiments, the reference voltage control signal includes a voltage waveform, and the voltage drop module is further configured to define the shape profile of the voltage waveform.

[0008] In some embodiments, the analog-to-digital module includes: an analog-to-digital converter (ADC) configured to process an analog input voltage; and a digital filter configured to filter the output of the ADC to generate a digital signal corresponding to the analog input voltage.

[0009] In some embodiments, the digital filter includes a low-pass filter.

[0010] In some embodiments, the digital-to-analog module includes a digital-to-analog converter (DAC) configured to process a reference control signal to generate a reference voltage.

[0011] In some embodiments, the voltage regulator module includes: a differential amplifier having a first input terminal configured to receive a reference voltage and a second input terminal configured to receive a sensed voltage; a power transistor having a gate terminal coupled to the output terminal of the differential amplifier; and a voltage divider coupled to the power transistor and the second input terminal of the differential amplifier.

[0012] In some embodiments, the voltage divider is configured to generate the sensed voltage.

[0013] In some embodiments, the drain terminal of the power transistor is coupled to the output node and the voltage divider.

[0014] In some embodiments, the voltage divider is configured to scale the voltage at the output node to a level equal to the reference voltage.

[0015] In some embodiments, the analog input voltage is received from a voltage source associated with a vehicle.

[0016] In some embodiments, the fixed voltage drop is configurable.

[0017] According to another aspect of the present disclosure, a transceiver is provided. In some embodiments, the transceiver includes a digital control loop for powering a sensor, the digital control loop including: an analog-to-digital module configured to receive an analog input voltage and generate a digital signal corresponding to the analog input voltage; a voltage drop module coupled to the analog-to-digital module, the voltage drop module being configured to receive one or more of a fixed voltage drop or a modulated voltage drop and generate a reference voltage control signal based on one or more of the fixed voltage drop or the modulated voltage drop; a digital-to-analog module coupled to the voltage drop module, the digital-to-analog module being configured to generate a reference voltage based on the reference voltage control signal; and a voltage regulator module coupled to the digital-to-analog module and at least one sensor, the voltage regulator module being configured to compare the reference voltage with the sensed voltage at an output node coupled to the at least one sensor and control the supply voltage of the sensor based on the comparison of the reference voltage with the sensed voltage.

[0018] In some embodiments, the voltage drop module of the digital control loop is configured to generate a reference voltage control signal by subtracting a fixed voltage drop from the digital signal corresponding to the analog input voltage, wherein the reference voltage control signal has a fixed value.

[0019] In some embodiments, the voltage drop module of the digital control loop is configured to generate a reference voltage control signal by applying a modulated voltage drop to the digital signal during forward communication configured to transmit a message to at least one sensor.

[0020] In some embodiments, the reference voltage control signal includes a voltage waveform, wherein the voltage drop module is further configured to define a shape profile of the voltage waveform.

[0021] In some embodiments, the analog-to-digital module of the digital control loop includes: an analog-to-digital converter (ADC) configured to process the analog input voltage; and a digital filter configured to filter the output of the ADC to generate a digital signal corresponding to the analog input voltage.

[0022] In some embodiments, the digital filter of the digital control loop includes a low-pass filter.

[0023] According to another aspect of the present disclosure, a method for controlling the voltage supply of a sensor is provided. In some embodiments, the method includes: receiving an analog input voltage; generating a digital signal corresponding to the analog input voltage; generating a reference voltage control signal by applying a fixed voltage drop to the digital signal; generating a reference voltage signal based on the reference voltage control signal; generating a control voltage based on comparing the reference voltage signal with the sensed voltage, wherein the control voltage is configured to control the supply voltage of the sensor.

[0024] The foregoing illustrative overview, as well as other exemplary objects and / or advantages of the present disclosure and its implementations, are further explained in the following detailed description and its accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The description of the illustrative embodiments may be read in conjunction with the accompanying drawings. It should be appreciated that, for simplicity and clarity of illustration, the elements shown in the figures are not necessarily drawn to scale unless otherwise described. For example, the dimensions of some elements may be exaggerated relative to other elements unless otherwise described. With respect to the figures presented herein, embodiments incorporating the teachings of the present disclosure are shown and described, in which:

[0026] Figure 1 An example block diagram of a digital control loop for sensor power supply according to at least one embodiment is provided.

[0027] Figure 2 An example block diagram of a digital control loop according to at least one embodiment is provided, which shows its various components.

[0028] Figures 3A - 3B A digital block environment is provided in which an example digital control loop can be implemented according to at least one example embodiment.

[0029] Figures 4A - 4C An example operation of a portion of a voltage waveform according to at least one embodiment is provided.

[0030] Figure 5 A flowchart depicting the operations of an example process for controlling the supply voltage of a sensor according to at least one embodiment is provided. DETAILED DESCRIPTION

[0031] Some embodiments of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all, embodiments of the present disclosure are shown. In fact, these disclosures may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like reference numerals refer to like elements throughout.

[0032] Terms such as "calculate", "determine", "generate", and / or similar words are used interchangeably herein to refer to the creation, modification, or identification of data. Additionally, "based on", "partially based on", "at least based on", "based upon", and / or similar words are used interchangeably herein in an open-ended manner such that unless so indicated, they do not indicate solely or only based on one or more of the recited elements. Like reference numerals always refer to like elements.

[0033] As used herein, terms such as "front", "rear", "top", etc. are used for explanatory purposes in the examples provided below to describe the relative positions of certain components or portions of components. Additionally, in accordance with the present disclosure, it will be apparent to those of ordinary skill in the art that the terms "substantially" and "approximately" indicate that the recited element or associated description is accurate within applicable engineering tolerances.

[0034] As used herein, the term "comprising" means including but not limited to and should be interpreted in the manner it is commonly used in the patent context. Use of the more general terms such as including, containing, and having should be understood to provide support for the more narrow terms such as consisting of, consisting essentially of, and consisting substantially of.

[0035] The phrases "in one embodiment", "according to one embodiment", etc. generally mean that the particular feature, structure, or characteristic following the phrase can be included in at least one embodiment of the present disclosure and can be included in more than one embodiment of the present disclosure (importantly, such phrases do not necessarily refer to the same embodiment).

[0036] The word "example" or "exemplary" is used herein to mean "serving as an example, instance, or illustration". Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other implementations.

[0037] If the specification states that a component or feature "may", "can", "could", "should", "would", "preferably", "possibly", "ordinarily", "optionally", "for example", "often", or "might" (or other such language) be included or have a certain property, then it is not required that the particular component or feature be included or have the property. Such a component or feature may optionally be included in some embodiments or it may be excluded.

[0038] As used herein, the term "or" is used in the alternative sense and the conjunctive sense, unless otherwise indicated. The terms "illustrative" and "example" are used as examples and do not indicate a level of quality. Terms such as "calculate", "determine", "generate", and / or similar words are used interchangeably herein to refer to the creation, modification, or identification of data. Additionally, "based on", "partially based on", "at least based on", "based upon", and / or similar words are used interchangeably herein in an open-ended manner such that they do not indicate only or solely based on the one or more recited elements, unless so indicated. Like reference numerals refer to like elements throughout.

[0039] Vehicles often include multiple different sensors (e.g., brake sensors, airbag sensors, seatbelt sensors, acceleration sensors, etc.). In many applications, these sensors are placed at the periphery of the vehicle. For example, many of these sensors are remote sensors. A sensor interface can be used to facilitate supplying voltage to the sensors and / or to facilitate communication between the sensors and the engine control unit (ECU) of the vehicle. For example, the sensor interface can be utilized to supply voltage to the sensor(s) of the vehicle and to transmit messages between the sensor(s) and the ECU. In various applications, due to cost and / or other reasons, the number of wires connecting the ECU to the sensors is limited. For example, conventional wiring interface standards / communication standards (such as PSI5, DSI3, and WSS standards) limit the number of wires connecting the ECU to the sensors to two wires. For example, for a system implementing such wiring interface standards / communication standards, a typical sensor can be a 2-wire sensor.

[0040] In automotive applications of sensors (e.g., sensors used in a braking system, an airbag system, a seatbelt system, etc.) that implement such standards (e.g., DSI3, PS15, and WSS) and are configured to supply voltage to the sensor(s), a transceiver must provide such supply voltage using a limited number of wires. It can be allowed to use a limited number of wires to supply the supply voltage to the sensor(s) and also communicate with the sensors (e.g., exchange messages between the sensor(s) and the ECU). For example, the supply wire(s) used to provide the supply voltage can also be used for forward communication from the transceiver to the sensors. Thus, the transceiver must finely control the voltage at the sensor supply wire(s). Moreover, the sensor(s) generally require a stable voltage, e.g., to limit and / or avoid variations in the current drawn by the sensor(s) - which can affect performance (e.g., message decoding errors, poor electromagnetic compatibility (EMC) performance, etc.).

[0041] Traditional solutions include several drawbacks, including for example: low configurability; a fixed regulated voltage with respect to ground that results in higher power dissipation; high sensitivity to noise in the power supply; and difficulty in managing the voltage transitions between the DC voltage value that causes higher emissions and the start / end of the communication pulse. In various systems, especially in automotive systems, there is a need for a low-cost, highly robust, and medium-speed interconnection limited to two wires (or three wires) that has good EMC performance, reduced / low power dissipation, and failsafe operation.

[0042] Embodiments of the present disclosure address the above drawbacks. Example embodiments of the present disclosure provide a digital control loop for sensor power supply that has improved performance and is particularly suitable for DSI3, PSI5, and WSS compatible systems. In various embodiments, the digital control loop is implemented within a transceiver or otherwise forms at least a part of the transceiver, where the transceiver is configured to function as a sensor interface. In various embodiments, the digital control loop is implemented as an integrated circuit (IC). For example, the digital control loop may be implemented within a transceiver IC.

[0043] In various embodiments, the digital control loop for sensor power supply is configured to generate a stable supply voltage for the sensor starting from an input voltage provided by an input voltage source (e.g., V HIGH ) in DSI3. For example, the digital control loop for sensor power supply may be configured to generate a stable supply voltage for a remote sensor starting from an input voltage provided by an input voltage source such as a battery. In various embodiments, the digital control loop for sensor power supply is configured to supply a regulated voltage to one or more sensors and provide a modulated voltage to one or more sensors. For example, various embodiments of the present disclosure relate to a digital control loop that is configured to supply a regulated voltage to one or more sensors and also modulate the regulated voltage for forward communication (e.g., transmit a message to one or more sensors).

[0044] Example embodiments provide several technical improvements / advantages. Example embodiments provide a digital control loop that is configured to generate a configurable supply voltage relative to the number of sensors connected - tracking the input voltage. Example embodiments provide a stable voltage at the sensor power supply, which in turn optimizes internal power dissipation, optimizes the power supply rejection ratio (PSRR) (e.g., increases the PSRR) and reduces noise (e.g., mitigates or eliminates the noise between the sensor(s) and the ECU during communication). As described herein, the voltage supplied to the sensor is a key factor in enabling accurate communication between the sensor (slave device) and the transceiver (master device).

[0045] The exemplary embodiments define an optimized shape for the voltage waveform profile during forward communication (e.g., during transmission of a message from an ECU to one or more sensors), which in turn results in low radiated and conducted emissions. The exemplary embodiments provide a digital control loop that limits the sensor supply voltage (e.g., in the case of a high input voltage) to a safe value to ensure normal operation of the sensors. The exemplary embodiments implement a soft start for the sensor supply, which reduces current spikes during transceiver turn-on and avoids voltage overshoot.

[0046] As described herein, a digital control loop according to an exemplary embodiment is configured to provide a regulated supply voltage to sensors (e.g., a vehicle speed sensor, a brake sensor, an airbag sensor, etc.) and also communicate with the sensors (e.g., transmit a message to the sensors). A transceiver according to an exemplary embodiment (e.g., implementing the digital control loop) can generate a stable voltage for a remote sensor starting from an input voltage source.

[0047] Figure 1 An exemplary block diagram of a digital control loop 100 for sensor supply according to at least one embodiment is provided. The digital control loop 100 can be implemented within a transceiver configured to serve as a sensor interface. In various embodiments, the digital control loop 100 is configured to supply a regulated voltage to one or more sensors (e.g., sensors external to the digital control loop 100) and modulate the regulated voltage during forward communication for supply to the one or more sensors. In some embodiments, the digital control loop 100 is implemented as an integrated circuit (IC). As described herein, the digital control loop 100 can be configured to provide a regulated supply voltage to a sensor (e.g., a sensor external to the digital control loop 100). For example, the sensor can be located external to the integrated circuit chip implementing the digital control loop 100. The sensor can be coupled to the digital control loop 100. The sensor can be configured to draw current when receiving the supply voltage and modulate the current through a line (e.g., a wire) connected to the sensor.

[0048] As described herein, the digital control loop 100 can be configured to modulate the supply voltage and supply the modulated voltage to the sensor to transmit one or more messages to the sensor. In various embodiments, to transmit a message to the sensor, the digital control loop 100 modulates the input voltage in a specific pattern (e.g., V HIGH to V LOW ) recognizable by the sensor. In this regard, the digital control loop 100 can be configured to generate a fixed voltage from the input voltage for supply to one or more sensors (e.g., when no message is being transmitted) and also be configured to modulate the voltage to transmit a message to the sensor (e.g., forward communication).

[0049] AsFigure 1 As shown in Figure 1 , the exemplary digital control loop 100 includes an input node 102, an analog-to-digital module 104, a voltage drop module 106, a digital-to-analog module 108, a voltage regulator module 110, and an output node 114. In various embodiments, the input node 102 is configured to receive an input voltage 101. The input voltage 101 may include an analog input voltage. The input voltage 101 may be received from an input voltage source (Vsup) such as, for example, a vehicle battery. The input source may be configured to provide the input voltage to the digital control loop 100 or other ECUs associated with the digital control loop 100. The input voltage source may have different values in different applications. For example, the input voltage source may supply a pre-regulated voltage shared with other functions. As another non-limiting example, the input voltage source may supply voltage directly from the battery line. For example, the input node may be connected to a vehicle battery or other input voltage source.

[0050] In various embodiments, the analog-to-digital module 104 is configured to receive the input voltage 101 via the input node 102 and generate a digital signal 105 (e.g., a digital code output) corresponding to the input voltage 101. In various embodiments, the voltage drop module 106 is configured to perform one or more digital processing operations on the digital signal 105 output of the analog-to-digital module 104 to generate a reference voltage control signal 107 (e.g., a digital code output). For example, the reference voltage control signal may include a digital code output corresponding to a reference voltage for regulating the voltage supplied by the digital control loop 100 to one or more sensors. The reference voltage control signal 107 may include a digital code output corresponding to a fixed reference voltage (e.g., when no message is sent to the (one or more) sensors). The reference voltage control signal 107 may include a digital code output corresponding to a voltage waveform (e.g., a voltage pulse) when a message is sent to the (one or more) sensors.

[0051] In various embodiments, the digital-to-analog module 108 is configured to receive the output of the reference voltage control signal 107 of the voltage drop module 106 and generate a reference voltage 109 based on the output of the reference voltage control signal 107 of the voltage drop module 106. In various embodiments, the voltage level / amplitude of the reference voltage 109 generally varies in a manner corresponding to the input voltage 101. In various embodiments, the voltage regulator module 110 is configured to receive the reference voltage 109 and the sensed voltage 111 at the output node 114. In various embodiments, the voltage regulator module 110 is configured to sense the voltage at the output node 114 (e.g., the sensed voltage 111). In various embodiments, the voltage regulator module 110 is configured to compare the reference voltage 109 with the sensed voltage 111. In various embodiments, in response to comparing the reference voltage 109 with the sensed voltage 111, the voltage regulator module 110 generates or otherwise controls an output voltage for powering a sensor coupled to the output node 114. The output voltage may include a regulated voltage having a fixed value (e.g., a fixed DC voltage). Alternatively or additionally, the output voltage may include voltage pulses (e.g., a modulated voltage).

[0052] Figure 2 An example block diagram of a digital control loop 100 according to at least one embodiment is provided, showing the various components of the digital control loop. In various embodiments, the digital control loop 100 may be implemented as an integrated circuit, include an integrated circuit, or otherwise implement an integrated circuit. In various embodiments, one or more sensors may be connected to the digital control loop 100. For example, one or more sensors may be connected to a transceiver integrated circuit implementing the digital control loop 100. In some embodiments, the sensor 250 may be connected to the transceiver integrated circuit by a single line. For example, in some embodiments, the sensor 250 and the transceiver integrated circuit may share a ground wire. In some embodiments, the sensor ground wire is not shared with the transceiver integrated circuit, such that there is one wire between the transceiver integrated circuit and the sensor 250.

[0053] As Figure 2As shown, analog-to-digital module 104 includes an analog-to-digital converter (ADC) 204. The ADC 204 can include a general-purpose ADC, a ΣΔ ADC, etc. In one example embodiment, the ADC includes a first-order ΣΔ ADC. For example, in some embodiments, the ADC 204 can include a first-order, single-bit continuous-time ΣΔ ADC. In various embodiments, the ADC 204 is configured to receive an input voltage 101 supplied by an input voltage source. In some embodiments, receiving the input voltage 101 includes monitoring and / or reading the input voltage 101 at the input node 102. For example, the ADC 204 can be configured to monitor and / or read the input voltage 101 at the input node 102 (e.g., the voltage on the input supply pin). The input node 102 can be directly connected to an input power source (e.g., a battery, etc.). For example, in Figure 2 the illustrated embodiment, the transceiver integrated circuit can be directly powered by a battery (VB). In various embodiments, the input voltage 101 is an analog input voltage. In various embodiments, the ADC 204 is configured to generate a digital signal 105 corresponding to the analog input voltage.

[0054] In some embodiments, and as Figure 2 shown, analog-to-digital module 104 includes an ADC calibration circuitry 206. The ADC calibration circuitry 206 can be configured to perform ADC calibration for the ADC 204 and / or the output of the ADC 204 to improve the accuracy of the voltage sensed at the input node 102 (e.g., sensed through the input supply pin). In various embodiments, the ADC calibration circuitry 206 performs ADC calibration based on temperature data and / or other data stored in a memory (e.g., data stored in a non-volatile memory (NVM)). Alternatively or additionally, in some embodiments, analog-to-digital module 104 includes a digital filter unit 208. The digital filter unit 208 can be configured to apply one or more digital filters to the output of the ADC 204 or the output of the ADC calibration circuitry 206 (when implemented) to mitigate or otherwise prevent instabilities and / or oscillations that may affect downstream processes associated with the digital control loop 100 (e.g., voltage regulation, voltage modulation, etc.). By applying one or more digital filters as described herein, various embodiments of the present disclosure improve the power supply rejection ratio (PSRR), which in turn enables stable sensor power supply and reduces noise. For example, in various embodiments, if the external power supply (e.g., the input voltage) changes (e.g., increases or decreases) during the operation of the transceiver integrated circuit, then the digital control loop 100 is configured to track the change and maintain the initial performance. In one example embodiment, one or more digital filters include a digital low-pass filter.

[0055] AsFigure 2 As shown, the digital control loop 100 includes moving from analog voltage information to digital information. For example, as Figure 2 depicted, the digital control loop 100 may include an analog domain (e.g., an analog portion) and a digital domain (e.g., a digital portion), where the digital control loop 100 may include moving from the analog domain to the digital domain and then back to the analog domain. For example, the digital control loop 100 may include moving from analog voltage information to digital voltage information and then back to analog voltage information. At least a portion of the analog-to-digital module 104 and the voltage drop module 106 may be associated with the digital domain.

[0056] In various embodiments, the voltage drop module 106 includes a subtractor 214. In various embodiments, the voltage drop module 106 is configured to perform digital processing on the digital signal 105 output (e.g., digital code) of the analog-to-digital module 104 to output a reference voltage control signal 107 (e.g., in the form of a digital code). In various embodiments, the subtractor 214 implements a fixed voltage drop and / or a modulated voltage drop logic to generate the reference voltage control signal 107.

[0057] As described above, the digital signal 105 output may correspond to or otherwise represent the digital equivalent of the analog input voltage 101. The reference voltage control signal 107 may include a digital code output corresponding to a reference voltage generated via the digital-to-analog module 108 of the digital control loop 100. The reference voltage may be configured to regulate and / or modulate the voltage supplied by the digital control loop 100 to one or more sensors. For example, the reference voltage control signal 107 may include a digital code output corresponding to a fixed reference voltage (e.g., when no message is being transmitted to the (one or more) sensors), or may include a digital code output corresponding to a voltage waveform (e.g., a voltage pulse) when a message is being transmitted to the (one or more) sensors.

[0058] The subtractor 214 can be configured to receive a digital signal 105 and a fixed voltage drop 212. In various embodiments, the fixed voltage drop 212 is a fixed value configured to be applied to the output of the digital signal 105 of the analog-to-digital module 104. In various embodiments, the fixed voltage drop 212 is configurable. For example, the subtractor 214 can be configured to receive the digital signal 105 output from the analog-to-digital module 104 and the configurable fixed voltage drop 212. In various embodiments, the configurable fixed voltage drop 212 is applied to the output of the digital signal 105 of the analog-to-digital module 104 at the voltage drop module 106 (e.g., in some embodiments, after ADC calibration and digital filtering) to adjust the input voltage for supply to the sensor 250 via the digital-to-analog module 108 and / or the voltage regulator module 110 of the digital control loop 100. In various embodiments, applying the configurable fixed voltage drop 212 to the digital signal 105 includes subtracting the fixed voltage drop 212 from the digital signal 105 using the subtractor 214. In this regard, the supply voltage for the sensor 250 can be dynamically generated logically using supply conversion data, where the supply voltage can correspond to a reference voltage generated at the digital-to-analog module 108 of the digital control loop 100 based on the reference voltage control signal 107. For example, the supply voltage for the sensor 250 can include an amplified reference voltage. For example, the reference voltage output can be amplified by a voltage division ratio to output the supply voltage for the sensor 250. The target supply voltage can correspond, for example, to the digital equivalent of the input voltage minus the fixed voltage drop (e.g., input voltage - fixed voltage drop). In this regard, in various embodiments, the voltage drop between the input node 102 and the regulated voltage supplied to the sensor 250 can be determined digitally. For example, a user can select a fixed voltage drop value that meets the user's desired supply voltage for the sensor 250. In some examples, the maximum voltage drop can be selected by default. As a non-limiting example, the maximum voltage drop can be 1V, for example, and can be selected by default. In this non-limiting example, the user can select a smaller voltage drop, for example, based on an external sensor configuration to further reduce power dissipation (e.g., based on a reduction in external sensor current consumption).

[0059] In various embodiments, and as Figure 2As shown, in addition to the fixed voltage drop 212, a modulated voltage drop 213 can also be applied at the voltage drop module 106 to modulate the regulated voltage for supply to the sensor 250 via the digital-to-analog module 108 and / or the voltage regulator module 110 of the digital control loop 100. For example, the subtractor 214 can be configured to receive the digital signal 105 output, the fixed voltage drop 212, and the modulated voltage drop 213 as inputs. The subtractor 214 can perform a subtraction operation including subtracting the fixed voltage drop 212 and the modulated voltage drop 213 from the digital signal 105 to generate a reference voltage control signal 107 including a digital code output corresponding to a voltage waveform generated based on the reference voltage control signal 107. For example, a digital voltage pulse can be generated based on applying the modulated voltage drop 213 at the voltage drop module 106. The digital voltage pulse can include, for example, a digital sine wave pulse. The digital voltage pulse can be fully utilized at the analog loop portion of the digital control loop 100 to generate a voltage waveform having a pattern recognizable by the sensor 250 and configured to convey a message to the sensor 250. In various embodiments, the voltage drop module 106 is configured to shape the digital voltage pulse (e.g., for forward communication). By way of example, as Figure 2 shown, a 7-bit subtraction can be applied to 10 bits of the voltage reading of the input voltage to generate a reference voltage control waveform of a desired shape. In some embodiments, the voltage drop module 106 includes or otherwise implements a soft start 210. For example, the voltage drop module 106 can implement a soft start of the sensor power supply, which reduces current spikes during transceiver turn-on and avoids voltage overshoot.

[0060] The digital-to-analog module 108 can be associated with the analog domain of the digital control loop 100. The digital-to-analog module 108 includes a digital-to-analog converter (DAC) 218 that is configured to generate a reference voltage corresponding to the supply voltage. For example, the DAC 218 can be configured to process the reference voltage control signal 107 to generate the reference voltage. In some embodiments, the output of the DAC 218 is amplified by a voltage division ratio by an adjustment section (e.g., at the voltage regulator module 110) to the sensor output. For example, the DAC 218 can be configured to output a reference voltage (e.g., an analog reference voltage) that can be amplified by a voltage division ratio. The DAC 218 can be configured to receive the reference voltage control signal 107 (e.g., in the form of a digital code) from a subtractor 214 that implements a fixed voltage drop and / or a modulated voltage drop logic and generate the reference voltage. For example, the DAC 218 can use the input received from the subtractor 214 (e.g., 10 bits, etc.) to generate the reference voltage. In some embodiments, DAC calibration can be performed on the output of the subtractor 214 before providing the output of the subtractor 214 as an input to the DAC 218. In some embodiments, the DAC calibration is performed based on temperature data and / or other data in the NVM.

[0061] The DAC 218 can generate a reference voltage for comparison with the sensed voltage (e.g., the sensed supply voltage) at the output node 114. In this regard, the digital voltage conversion using the analog-to-digital module can be used to drive the DAC 218 that is configured to generate the reference voltage for the voltage regulator module 110. The DAC 218 can be configured to generate a reference voltage with a fixed value (e.g., a fixed DC value) in response to receiving a reference voltage control signal 107 that includes a fixed voltage value. The DAC 218 can be configured to generate a reference voltage that includes a voltage waveform in response to receiving a reference voltage control signal 107 that includes a digital voltage pulse. In some embodiments, an RC filter 220 is coupled to the DAC 218 to smooth any sharp transitions in the shape of the voltage waveform generated via the DAC. For example, the digital-to-analog module 108 can include an RC filter 220 that is configured to filter the output of the DAC. The RC filter can include one or more resistors and / or one or more capacitors.

[0062] By implementing a reference voltage that includes a fixed voltage (e.g., V HIGH ) during message-free transmission and a voltage waveform (e.g., from V HIGH to V LOW and from V LOW to V HIGHFor a fully digital implementation of a reference voltage (for a transition), embodiments of the present disclosure define an optimal shape of a voltage profile during forward communication, which in turn results in low radiated and conducted emissions.

[0063] The voltage regulator module 110 may be associated with the analog domain of the digital control loop 100. In various embodiments, the voltage regulator module 110 includes a power transistor 228, a differential amplifier 230, and a voltage divider 226, which together define a voltage regulator. The voltage regulator may correspond to or otherwise include a linear regulator or other voltage regulator. In various embodiments, the differential amplifier is configured to compare a sensed voltage (e.g., the voltage at output node 114) with a reference voltage in order to provide a stable supply voltage for the sensor. By providing a stable supply voltage for the sensor, embodiments of the present disclosure optimize the performance of the transceiver. For example, the performance of the transceiver with respect to various performance parameters of the transceiver may be at least partially based on the supply voltage used for the sensor.

[0064] In various embodiments, the digital control loop 100 is configured to ensure that the supply voltage is lower than the input voltage multiplied by the transceiver R ON , which keeps the power transistor 228 in the saturation region in order to generate a higher PSRR. Alternatively or additionally, in various embodiments, the digital control loop 100 is configured to optimize power dissipation. For example, the internal power dissipation may increase as the input voltage (V SUP ) to the output voltage (V HIGH ) drops. In this regard, the performance of the transceiver with respect to PSRR may be at least partially based on the supply voltage for the sensor, where example embodiments of the present disclosure are configured to control the supply voltage and thereby improve PSRR, power dissipation, and other performance parameters associated with the transceiver. Various embodiments provide a stable supply voltage or otherwise use information from an existing ADC already present in the supply line to optimize the supply voltage.

[0065] The differential amplifier 230 may include a first input terminal configured to receive a reference voltage and a second input terminal configured to receive a sensed voltage. As Figure 2As shown in the figure, the differential amplifier 230 includes a non-inverting input terminal 222 configured to receive a reference voltage and an inverting input terminal 224 configured to receive a sensed voltage. The gate of the power transistor 228 (e.g., MOSFET, etc.) can be coupled to the output terminal of the differential amplifier 230. The source terminal of the power transistor 228 can be indirectly or directly coupled to the input node 102, and the drain terminal of the power transistor 228 can be coupled to the output node 114. For example, in some embodiments, the source terminal of the power transistor 228 can be indirectly coupled to the input node 102 via another transistor (e.g., MOSFET, etc.). In various embodiments, the sensed voltage is sensed by a voltage divider 226 coupled to the output node 114 and ground. As Figure 2 shown in the figure, the voltage divider 226 is coupled to the power transistor 228 and the second input terminal of the differential amplifier 230. In some embodiments, the differential amplifier 230 is configured to output a control voltage (e.g., an error) based on the reference voltage and the sensed voltage. The control voltage can be configured to drive the power transistor 228 to supply voltage to the sensor and / or control the supply voltage of the sensor. In some embodiments, the voltage divider 226 is configured to scale the voltage at the output node to a level equal to the reference voltage. For example, the power transistor 228 can drive the voltage divider 226 to scale the voltage at the output node to a level equal to the reference voltage.

[0066] In some embodiments, the second regulator can be connected to an input voltage source (e.g., a battery) to generate a voltage lower than the input voltage source. For example, the second regulator can be a pre-regulator that feeds a certain DC voltage to the transceiver integrated circuit. In some examples, the second regulator can include a bipolar transistor and a capacitor.

[0067] Figures 3A - 3B A digital block environment is provided in which the digital control loop 100 can be implemented according to at least one exemplary embodiment. Specifically, Figure 3A A digital block 302 for ADC conversion and filtering is depicted. Figure 3A It can represent a specific implementation of the analog-to-digital module 104. Figure 3A An input voltage 304 (e.g., VDSI input voltage) and a model 306 of the analog portion of the ADC are also shown. Figure 3B A digital block 308 for controlling the DAC input code (e.g., reference voltage control signal) is depicted. For example, the digital block 308 for controlling the DAC input code can implement or otherwise implement soft start, voltage drop, and / or sine wave pulse generation associated with the voltage drop module 106. As Figures 3A - 3BAs shown, example embodiments of the present disclosure may be implemented by one or more integrated chips. For example, one or more modules of the digital control loop 100 may be implemented by one or more integrated chips.

[0068] Figures 4A - 4C An operating example of a portion of a voltage waveform according to at least one embodiment is provided. Specifically, Figure 4A A portion of the voltage waveform 404 output of the voltage drop module 106 of the digital control loop 100 is provided. Figure 4B and Figure 4C each provide a Figure 4A close-up view of a portion of the voltage waveform 404 depicted in. As described herein, the voltage drop module 106 of the digital control loop 100 can be fully utilized to generate the voltage waveform 404 based on the input voltage 402. As described herein, the voltage drop module 106 can be configured to apply a voltage drop and / or a modulated voltage drop to a digital signal corresponding to the input voltage 402 to generate a voltage waveform 404 having a specific pattern (e.g., V HIGH to V LOW ) that can be recognized by a sensor. For example, the voltage waveform 404 may include voltage pulses having a pattern that can be recognized by a sensor and is configured to convey a message to the sensor. The voltage waveform 404 may have a configurable slew rate (e.g., the rate of change of voltage per unit time). As described herein, the voltage drop module 106 can be configured to shape the voltage waveform 404 (e.g., define the shape profile of the voltage waveform 404). As Figure 4C shown in, digital steps can be smoothed, for example, by an RC filter such as the RC filter 220. The RC filter can be configured to smooth any sharp transitions in the shape of the voltage pulses generated by the DAC.

[0069] Some embodiments of the present disclosure use information from an ADC already present on the power supply line to optimize the output voltage (V HIGH ) for diagnostic purposes. The all-digital regulation reference of the example embodiments of the present disclosure allows for a less complex implementation with a small area impact and test time. In addition, the all-digital implementation of the reference voltage (V HIGH ) during transmission and the modulated reference voltage (from V HIGH to V LOW and the transition from V LOW to V HIGH ) during transmission to the sensor in the example embodiments of the present disclosure enables the optimization of the shape of the voltage profile to be defined during forward communication, which results in low radiation and conducted emissions. By implementing control in digital form, the embodiments of the present disclosure reduce the area occupied and provide higher test efficiency.

[0070] Example processes of the present disclosure will now be discussed. It will be appreciated that each flow chart depicts an example computer-implemented process that may be performed by one or more of the apparatuses, systems, devices, and / or computer program products described herein, for example, using one or more of its specially configured components.

[0071] Although the example processes depict a particular sequence of operations, the sequence may be changed without departing from the scope of the present disclosure. For example, some of the depicted operations may be performed in parallel or in a different sequence that does not materially affect the functionality of the process.

[0072] The boxes indicate the operations of each process. Such operations may be performed in any of a variety of ways, including but not limited to in the order and manner depicted and described herein. In some embodiments, one or more of the boxes of any of the processes described herein occur between one or more of the boxes of another process, before one or more of the boxes of another process, in parallel with one or more of the boxes of another process, and / or as a sub-process of a second process. Additionally or alternatively, any of the processes in various embodiments includes some or all of the operation steps described and / or depicted, including one or more optional boxes in some embodiments. With respect to the flow charts shown herein, one or more of the (one or more) boxes depicted in some embodiments are optional in some or all embodiments of the present disclosure. Optional boxes are depicted with a broken line (or "dashed line"). Similarly, it should be appreciated that one or more of the operations of each flow chart may be combinable, replaceable, and / or otherwise changed as described herein.

[0073] Figure 5 A flow chart illustrating example operations depicting an example process for controlling the supply voltage of a sensor in accordance with at least one example embodiment is shown. Specifically, Figure 5 An example process 500 is depicted that is configured to regulate the voltage supply to a sensor and modulate the voltage supply to transmit a message to the sensor. In some embodiments, process 500 is performed by one or more specially configured computing devices, such as a device that communicatively implements a digital control loop 100 alone or in combination with one or more other components, (one or more) devices, (one or more) systems, etc. In some embodiments, the device includes the digital control loop 100. In some embodiments, the device includes a transceiver that implements the digital control loop 100. In some embodiments, the device communicates with one or more external devices, (one or more) systems, (one or more) devices, etc. to perform one or more of the operations depicted and described. For example, the device in some embodiments communicates with a controller (e.g., an ECU) etc. to perform one or more of the operations depicted and described.

[0074] Although example process 500 depicts a particular sequence of operations, the sequence can be changed without departing from the scope of the present disclosure. For example, some of the depicted operations can be performed in parallel or in a different sequence that does not materially affect the functionality of process 500. In other examples, different components of an example device or system implementing process 500 can perform functions substantially simultaneously or in a particular sequence.

[0075] According to some examples, the method includes receiving an analog input voltage at block 502. In some embodiments, the analog input voltage can be received from a voltage source associated with a vehicle, such as an external circuit system within the vehicle. For example, the device can receive an analog input voltage from an input voltage source such as, for example, a battery (e.g., a vehicle battery). The input voltage source can have different values in different applications. By way of example, the input voltage source can supply a pre-regulated voltage that is shared with other functions. As another non-limiting example, the input voltage source can supply voltage directly from a battery line. For example, the input node can be connected to a vehicle battery or other input voltage source.

[0076] According to some examples, the method includes generating a digital signal corresponding to the analog input voltage at block 504. The device can utilize an ADC to generate the digital signal. In some embodiments, the device can utilize an ADC to monitor and / or read the input voltage at an input node coupled to the input voltage source and the ADC. The input node can be directly connected to an input power supply (e.g., a battery, etc.). For example, the device can be directly powered by a battery. The input voltage 101 can be an analog voltage. In some embodiments, the device utilizes one or more of ADC calibration or digital filtering to optimize the digital signal. The device can perform ADC calibration on the output of the ADC to improve the accuracy of the voltage sensed at the input node. Alternatively or additionally, in some embodiments, the device can apply one or more digital filters (e.g., a digital low-pass filter, etc.) to the output of the ADC (e.g., after ADC calibration) to mitigate or otherwise prevent instabilities and / or oscillations that can affect the regulation and / or modulation of the voltage supplied to the sensor.

[0077] According to some examples, the method includes generating a reference voltage control signal at block 506. The apparatus may be configured to generate the reference voltage control signal based on applying one or more of a fixed voltage drop or a modulated voltage drop to a digital signal output (e.g., from block 504). In various embodiments, the fixed voltage drop is a configurable value. In various embodiments, the fixed voltage drop is applied to the digital signal to regulate the voltage supplied to the sensor via the analog portion. For example, the supply voltage for the sensor may be dynamically generated by logic using supply conversion data. For example, the supply voltage for the sensor may be generated based at least in part on subtracting the fixed voltage drop from a digital signal corresponding to the input voltage and amplifying the output based on a voltage division ratio.

[0078] In various embodiments, in addition to the fixed voltage drop, the apparatus may also apply a modulated voltage drop to the digital signal to generate a reference voltage control signal that includes digital voltage pulses. In some embodiments, the digital voltage pulses include digital sine wave pulses. The apparatus may be configured to shape the digital voltage pulses for forward communication (e.g., define a shape profile). By way of example, the digital signal output may have a resolution of 10 bits. In some embodiments, the modulated voltage drop may have a resolution of 7 bits. In some embodiments, the reference voltage control signal may have a resolution of 10 bits. It will be appreciated that in other embodiments, the digital signal, the modulated voltage drop, and / or the reference voltage control signal may have different resolutions. In some embodiments, the apparatus may perform DAC calibration on the reference voltage control signal. In some embodiments, the DAC calibration is performed based on temperature data and / or NVM data.

[0079] According to some examples, the method includes generating a reference voltage at block 508. The apparatus may include a DAC configured to generate a reference voltage corresponding to a desired supply voltage based on the reference voltage control signal. The reference voltage may include a fixed voltage (e.g., when there is no communication) or a voltage waveform (e.g., for forward communication). In some embodiments, the reference voltage is amplified (e.g., based on a voltage division ratio). In some embodiments, the apparatus includes an RC filter 220 configured to smooth any sharp transitions in the shape of the voltage waveform generated by the DAC. The RC filter may include one or more resistors and / or one or more capacitors.

[0080] According to some examples, the method includes generating a control voltage at block 510 based on a reference voltage signal and a sensed voltage. The apparatus may include a voltage regulator. The voltage regulator may include, for example, a linear voltage regulator and the like. In some embodiments, the voltage regulator may include a power transistor, a differential amplifier, and a voltage divider. In various embodiments, the apparatus uses the differential amplifier to compare the sensed voltage at an output node coupled to the sensor and the voltage divider with the reference voltage to generate a control voltage (e.g., an error). The voltage divider may be configured to sense the voltage at the output node. In various embodiments, the control voltage is configured to drive the power transistor to supply voltage to the sensor and / or control the supply voltage to the sensor. The power transistor may drive the voltage divider to scale the supply voltage based on the control voltage.

[0081] Conclusion

[0082] Those skilled in the art to which the present disclosure pertains, having the benefit of the foregoing description and the teachings presented in the related drawings, will conceive of many modifications and other embodiments of the present disclosure set forth herein. Accordingly, it is to be understood that the embodiments are not limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Moreover, although the foregoing description and the related drawings describe example embodiments in the context of certain example combinations of elements and / or functions, it should be recognized that different combinations of elements and / or functions may be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, combinations of elements and / or functions different from those explicitly described above are also contemplated, as may be set forth in some of the appended claims. Although specific terms are employed herein, they are used in a general and descriptive sense only and not for purposes of limitation.

[0083] Although this specification contains many specific implementation details, these should not be construed as limitations on the scope of any disclosure or of what may be claimed, but rather as descriptions of features specific to particular embodiments of a particular disclosure. Certain features described herein in the context of separate embodiments may also be implemented in combination within a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented separately or in any suitable sub-combination in multiple embodiments. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, in some cases, one or more features from a claimed combination may be deleted from the combination, and the claimed combination may be directed to a sub-combination or a variant of a sub-combination.

[0084] Similarly, although the operations are depicted in the drawings in a particular order, this should not be construed as requiring that such operations be performed in the particular order shown or in sequential order, or that all of the illustrated operations be performed, to achieve the desired result. In some cases, multitasking and parallel processing may be advantageous. Also, the separation of various system components in the above-described embodiments should not be construed as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single product or packaged into multiple products.

[0085] Accordingly, particular embodiments of the subject matter have been described. Other embodiments are within the scope of the appended claims. In some cases, the operations recited in the claims may be performed in a different order and still achieve the desired result. Additionally, the processes depicted in the drawings do not necessarily require the particular order or sequential order shown to achieve the desired result. In some implementations, multitasking and parallel processing may be advantageous.

[0086] Furthermore, although this detailed description has set forth some embodiments of the present disclosure, the appended claims may cover other embodiments of the present disclosure that are different from the described embodiments according to various modifications and improvements. For example, in some embodiments, the voltage regulator may include a linear voltage regulator or other types of voltage regulators. As another example, in some embodiments, the fixed voltage drop may be non-configurable. As yet another example, in some embodiments, the ADC calibration and / or DAC calibration may not be performed.

[0087] Moreover, within the appended claims, unless the specific terms "means for... " or "step for... " are used in a given claim, there is no intention to invoke 35 U.S.C.§ 112, paragraph (f) to interpret that claim.

Claims

1. A digital control loop for powering a sensor, comprising: An analog-to-digital module configured to receive an analog input voltage and generate a digital signal corresponding to the analog input voltage; A voltage drop module coupled to the analog-to-digital module, the voltage drop module being configured to receive one or more of a fixed voltage drop or a modulated voltage drop and generate a reference voltage control signal based on one or more of the fixed voltage drop or the modulated voltage drop; A digital-to-analog module coupled to the voltage drop module, the digital-to-analog module being configured to generate a reference voltage based on the reference voltage control signal; And A voltage regulator module coupled to the digital-to-analog module and at least one sensor, the voltage regulator module being configured to compare the reference voltage with the sensed voltage at an output node coupled to the at least one sensor and control the supply voltage of the sensor based on the comparison of the reference voltage with the sensed voltage.

2. The digital control loop according to claim 1, wherein, The voltage drop module is configured to generate a reference voltage control signal by subtracting a fixed voltage drop from the digital signal corresponding to the analog input voltage, wherein the reference voltage control signal has a fixed value.

3. The digital control loop according to claim 2, wherein The voltage drop module is configured to generate a reference voltage control signal by applying a modulated voltage drop to the digital signal during a forward communication configured to transmit a message to the at least one sensor.

4. The digital control loop according to claim 3, wherein, The reference voltage control signal includes a voltage waveform, wherein the voltage drop module is further configured to define the shape profile of the voltage waveform.

5. The digital control loop according to claim 1, wherein The analog-to-digital module includes: An analog-to-digital converter ADC configured to process the analog input voltage; and A digital filter configured to filter the output of the ADC to generate a digital signal corresponding to the analog input voltage.

6. The digital control loop according to claim 5, wherein, The digital filter includes a low-pass filter.

7. The digital control loop according to claim 1, wherein, The digital-to-analog module includes: A digital-to-analog converter DAC configured to process the reference voltage control signal to generate a reference voltage.

8. The digital control loop according to claim 1, wherein, The voltage regulator module includes: A differential amplifier having a first input terminal configured to receive the reference voltage and a second input terminal configured to receive the sensed voltage; A power transistor having a gate terminal coupled to the output terminal of the differential amplifier; and A voltage divider coupled to the power transistor and the second input terminal of the differential amplifier.

9. The digital control loop according to claim 8, wherein The voltage divider is configured to generate the sensed voltage.

10. The digital control loop according to claim 8, wherein, The drain terminal of the power transistor is coupled to the output node and the voltage divider.

11. The digital control loop according to claim 10, wherein, The voltage divider is configured to scale the voltage at the output node to a level equal to the reference voltage.

12. The digital control loop according to claim 1, wherein The analog input voltage is received from a voltage source associated with a vehicle.

13. The digital control loop according to claim 1, wherein, The fixed voltage drop is configurable.

14. A transceiver, comprising: A digital control loop for powering a sensor, the digital control loop including: An analog-to-digital module configured to receive an analog input voltage and generate a digital signal corresponding to the analog input voltage; A voltage drop module, the voltage drop module being coupled to an analog-to-digital module, the voltage drop module being configured to receive one or more of a fixed voltage drop or a modulated voltage drop and generate a reference voltage control signal based on one or more of the fixed voltage drop or the modulated voltage drop; A digital-to-analog module, the digital-to-analog module being coupled to the voltage drop module, the digital-to-analog module being configured to generate a reference voltage based on the reference voltage control signal; and A voltage regulator module, the voltage regulator module being coupled to the digital-to-analog module and at least one sensor, the voltage regulator module being configured to compare the reference voltage with the sensed voltage at an output node coupled to the at least one sensor and control the supply voltage of the sensor based on the comparison of the reference voltage with the sensed voltage.

15. The transceiver according to claim 14, wherein, The voltage drop module of the digital control loop is configured to generate a reference voltage control signal by subtracting a fixed voltage drop from a digital signal corresponding to an analog input voltage, wherein the reference voltage control signal has a fixed value.

16. The transceiver according to claim 15, wherein, The voltage drop module of the digital control loop is configured to generate a reference voltage control signal by applying a modulated voltage drop to a digital signal during a forward communication configured to transmit a message to the at least one sensor.

17. The transceiver according to claim 16, wherein, The reference voltage control signal includes a voltage waveform, wherein the voltage drop module is further configured to define the shape profile of the voltage waveform.

18. The transceiver according to claim 14, wherein, The analog-to-digital module of the digital control loop includes: An analog-to-digital converter ADC configured to process an analog input voltage; and A digital filter configured to filter the output of the ADC to generate a digital signal corresponding to the analog input voltage.

19. The transceiver according to claim 18, wherein, The digital filter of the digital control loop includes a low-pass filter.

20. A method for controlling the voltage supply for a sensor, the method comprising: Receiving an analog input voltage; Generating a digital signal corresponding to the analog input voltage; Generating a reference voltage control signal by applying a fixed voltage drop to the digital signal; Generating a reference voltage signal based on the reference voltage control signal; and And Generating a control voltage based on comparing the reference voltage signal with the sensed voltage, wherein the control voltage is configured to control the supply voltage for the sensor.

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