TIME-DEPENDENT OVERTEMPERATURE PROTECTION

Abstract

A method for overtemperature protection of an electronic device (112) is presented. The method comprises: a) monitoring a temperature of at least a portion of the electronic device (112); b) start monitoring a temperature overshoot time when the temperature exceeds a temperature threshold; and c) declaring an over-temperature condition of the electronic device (112) when the time of the temperature over-exceedance exceeds a time threshold. Furthermore, an overtemperature detection circuit (110) and a use of the overtemperature detection circuit (110) and the method for overtemperature protection are presented.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a method for over-temperature protection, an over-temperature detection circuit and a use thereof. BACKGROUND

[0002] Overtemperature operation can generally destroy or at least damage electronic devices, and in particular semiconductor devices. At the very least, overtemperature operation can reduce the lifetime of such devices or lead to operational failures of the same. Additionally or alternatively, the overtemperature can cause failure or malfunction of such devices. Therefore, overtemperature detection and protection is typically required. However, such devices typically comprise a plurality of different materials, and each material can exhibit different properties, particularly with regard to temperature behavior. As one example, a printed circuit board material can exhibit different temperature behavior compared to a semiconductor material. Thus, the different materials can have different operating temperature ranges.In other words, temperature thresholds for overtemperature operation may be different for them. As an example, the aforementioned circuit board material may have a lower temperature threshold for overtemperature operation than the semiconductor material. However, the circuit board material may be able to withstand its respective lower temperature threshold for overtemperature operation, at least for a limited period of time. In general, materials can be robust with respect to high operating temperatures for at least short periods of time. Therefore, there is a need to improve overtemperature protection, and in particular to benefit from robustness to high operating temperatures over limited periods of time. SUMMARY

[0003] In a first aspect, a method for overtemperature protection of an electronic device is presented. The method comprises: a) monitoring a temperature of at least a part of the electronic device; b) Start monitoring an over-temperature period when the temperature exceeds a temperature threshold; c) Declaring an over-temperature condition of the electronic device when the temperature over-temperature time exceeds a time threshold.

[0004] In another aspect, an overtemperature detection circuit is presented. The overtemperature protection circuit includes a temperature comparator. The temperature comparator is configured to receive a temperature signal related to a temperature of at least a portion of an electronic device. The temperature comparator is further configured to compare the temperature to a temperature threshold. The overtemperature protection circuit further includes an evaluation circuit. The evaluation circuit is configured to evaluate a time of the temperature exceedance. The evaluation circuit is further configured to declare an overtemperature condition of the electronic device if the time of the temperature exceedance exceeds a time threshold.

[0005] In another aspect, a use of a method for overtemperature protection or an overtemperature detection circuit for an automotive application is presented.

[0006] Those skilled in the art will recognize additional features and advantages upon reading the following detailed description and examining the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The present disclosure is illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like reference numerals refer to similar or identical elements. The elements of the drawings are not necessarily to scale relative to one another. The features of the various examples illustrated may be combined, provided they are not mutually exclusive. Fig. 1a and Fig. 1b schematically shows examples of an overtemperature detection circuit in connection with a monitored electronic device; Fig. 2a to Fig. 2c schematically show examples of an evaluation circuit of an overtemperature detection circuit; Fig. 3 schematically shows another example of an overtemperature detection circuit; and Fig. 4 shows a flowchart of an example of an overtemperature protection method. DETAILED DESCRIPTION

[0008] The examples described here provide significant advantages. In particular, the presented methods and devices can utilize the robustness of a device to high operating temperatures over limited periods of time. In particular, the presented methods and devices can implement time-dependent overtemperature protection. Thus, a period of overtemperature operation can be monitored, and protective measures can be taken only if the overtemperature operation lasts too long. In other words, a temperature threshold can be associated with a time dependency. In addition, another temperature threshold without a time dependency can be used to specify a temperature that should not be exceeded, even for a short period of time.Thus, the two temperature thresholds can define a temperature range that is tolerable for operation for a short period of time, in particular without further damage or at least without further significant damage to a device or without failure or malfunction of the device. As a result, the operating range of the device can be extended. In particular, short-term operation at high temperatures can be enabled.

[0009] Fig. 1a schematically shows an example of an overtemperature detection circuit 110 in connection with a monitored electronic device 112. Thus, the overtemperature detection circuit 110 may be configured to detect an overtemperature condition at the electronic device 112, in particular a damaging overtemperature condition or at least a significantly damaging overtemperature condition. The overtemperature condition may refer to a condition in which the electronic device 112 is operating at a temperature that causes damage or at least significant damage to the electronic device 112, or a failure or malfunction of the electronic device 112. In principle, the electronic device 112 may be any device that includes electronic components. In particular, the electronic device 112 may be or include a semiconductor device.The electronic device 112 may be or include an integrated circuit. The electronic device 112 may be configured to directly or indirectly control an application, in particular an automotive application, e.g., a motor or a light-emitting diode. The electronic device 112 may be or include a circuit board 114 or at least a portion thereof. The circuit board 114 may be at least partially enclosed by a housing 116. The circuit board 114 may include at least one semiconductor die 118. The semiconductor die 118 may be or include an integrated circuit. The semiconductor die 118 may be enclosed by a housing 120. The semiconductor die 118 may further be soldered to the circuit board 114 using a solder 122. For example, depending on the application, the electronic device 112 may include the semiconductor die 118 or even the entire circuit board 114.The circuit board 114 may include a plurality of semiconductor dies 118 or other components, as indicated by dots 124, which may be at least partially interconnected by wires or traces.

[0010] The overtemperature detection circuit 110 may include a temperature sensor 126. The temperature sensor 126 may be configured to monitor the temperature of the electronic device 112 or at least a portion thereof. For example, the temperature sensor 126 may be or include a thermistor. The thermistor may be a negative temperature coefficient thermistor or a positive temperature coefficient thermistor. Other options may also be possible. For example, the temperature sensor 126 may be configured to monitor a temperature of the circuit board 114 and / or the semiconductor die 118. The temperature sensor 126 may be located on the electronic device 112. As shown, the temperature sensor 126 may be located on the circuit board 114. However, the temperature sensor 126 may also be located on the semiconductor die 118, or an additional temperature sensor 126 may be located on the semiconductor die 118.The overtemperature detection circuit may also include a plurality of temperature sensors 126, particularly at different locations and for monitoring different areas. Temperature sensor 126 may be configured to send a temperature signal corresponding to the monitored temperature.

[0011] The temperature signal may be an analog temperature signal, at least initially. However, the analog temperature signal may subsequently be converted into a digital temperature signal. The overtemperature detection circuit 110 may include an analog-to-digital converter 128. The analog-to-digital converter 128 may be configured to convert the analog temperature signal into the digital temperature signal. Thus, the overtemperature detection circuit 110 may be at least partially a digital device. In other words, at least some of the components of the overtemperature detection circuit 110 described below may be digital components. In principle, however, the overtemperature detection circuit 110 may also be an analog device. In other words, the components of the overtemperature detection circuit 110 described below may also be analog components.In general, the overtemperature detection circuit 110 may be or include an integrated circuit.

[0012] The overtemperature detection circuit 110 includes a temperature comparator 130. The temperature comparator 130 is configured to receive a temperature signal related to a temperature of at least a portion of the electronic device 112. The temperature comparator 130 is further configured to compare the temperature to a temperature threshold. As indicated, the temperature comparator 130 may be an analog or a digital component. The temperature comparator 130 may be or include an electronic circuit configured to compare two voltages. A first voltage may relate to the temperature at the electronic device 112. A second voltage may relate to the temperature threshold. An output of the temperature comparator 130 may indicate which voltage is higher and thus whether the temperature at the electronic device 112 is higher than the temperature threshold.Thus, the temperature comparator 130 may indicate whether a temperature at the electronic device 112 is at or above the temperature threshold.

[0013] The temperature threshold may be predetermined. Thus, the temperature threshold may be a predetermined temperature value or a corresponding voltage value applied to the temperature comparator 130. As an example, the temperature threshold may be in a range from 80°C to 270°C, in particular from 100°C to 200°C, more specifically from 130°C to 175°C. As a specific example, the temperature threshold may be 135°C. In particular, the temperature threshold may be tailored to at least one material included in the electronic device 112, or more specifically to a temperature resistance of the material. More specifically, the temperature threshold may be tailored to a material with a low temperature resistance or even to a least temperature-resistant material of the electronic device 112.As one example, the temperature threshold may be tailored to a component of the electronic device 112, such as the circuit board 114, the housing 116, the case 120, or the solder 122. Thus, the temperature threshold may be selected to prevent damage, deterioration, or failure of such a component. The component may comprise at least one of a synthetic material, a molded resin, and a composite material, particularly of the FR4 class. Thus, the temperature threshold may be a transition temperature of such a material, particularly a glass transition temperature. However, damage to the component may not necessarily occur immediately when the temperature threshold is exceeded. A brief temperature exceedance may not damage the electronic device 112, or at least not significantly. Only a sufficiently long temperature exceedance can do so.Thus, monitoring a time of temperature overshoot may extend an operating range of the electronic device 112.

[0014] The overtemperature protection circuit 110 further includes an evaluation circuit 132. The evaluation circuit 132 is configured to evaluate a time of the temperature exceedance. The evaluation circuit 132 is further configured to declare an overtemperature condition of the electronic device 112 if the time of the temperature exceedance exceeds a time threshold. The time threshold can be an individual time threshold. Thus, when a temperature exceedance is detected by the temperature comparator 130, the evaluation circuit 132 can evaluate how long the temperature exceedance lasts, in particular uninterrupted or continuous. However, the time threshold can also be an accumulated time threshold. The accumulated time threshold can take into account a plurality of individual temperature exceedances over time.Thus, the accumulated time threshold may be a total time threshold for the plurality of individual temperature exceedances over time. As an example, the temperature threshold may be exceeded for a first period of time. After the first period of time, the temperature at the electronic device 112 may again be below the temperature threshold. However, the temperature threshold may then be exceeded for a second period of time. In this example, the sum of the first period of time and the second period of time may be compared to the accumulated time threshold. Each temperature exceedance may damage the electronic device 112 by at least one bit, and the accumulated time threshold may thus account for total damage to the electronic device 112 over time.

[0015] The time threshold may be predetermined. Thus, the time threshold may be a fixed time value, e.g., in a range from 1 ms to 100 h, in particular from 10 ms to 1 min, more precisely from 100 ms to 10 s. A time threshold of 100 h may, for example, be used for an accumulated time threshold. An individual time threshold, which may, for example, be used with respect to an engine start or a capacitor charging, may typically be in a range of a few milliseconds or seconds. Such events may occur regularly, particularly in automotive applications, and may heat control electronics above a temperature threshold, for example, of the circuit board 114 or at least a portion thereof. However, such events may only be temporary, and the circuit board 114 may be able to withstand such brief overheating, at least without further significant damage or failure.

[0016] However, the time threshold may also be variable. In particular, the time threshold may also be a function of the temperature, in particular the temperature at the electronic device 112, e.g., at the circuit board 114 or at least a part thereof, or at the housing 120, or at the solder 122. The function may, in particular, comprise an integral of the temperature over time. Thus, the time threshold may vary depending on the temperature at the electronic device 112. This may, in particular, take into account further temperature variations, in particular a further temperature increase, at the electronic device 112. As one example, the temperature at the electronic device 112 may continue to rise after exceeding the temperature threshold, which may impose additional stress on the electronic device 112 and thus further damage the electronic device 112.To account for this additional load, for example, an integral of the temperature over time can be evaluated. Thus, the time threshold can also be a threshold for the time integral of the temperature, or simply a time integral threshold.

[0017] As stated, the evaluation circuit 132 is configured to declare an overtemperature condition of the electronic device 112 if the time of the temperature exceedance exceeds a time threshold. The evaluation circuit 132 may further be configured to output or display the overtemperature condition to the electronic device 112, in particular to trigger a remedial action. Thus, the evaluation circuit 132 may further be configured to initiate a reaction to the overtemperature condition. The reaction may include triggering a safe state of the electronic device 112. The safe state may, in particular, be an off state of the electronic device 112. In other words, the electronic device may be switched off in the event of an overtemperature condition. However, other safe states may also be possible. In principle, the safe state may also be an on state, e.g.an on state with reduced power consumption.

[0018] Additionally or alternatively, the response may include activating cooling of the electronic device 112. Thus, for example, a cooling element, e.g., a fan or a thermoelectric cooler such as a Peltier cooler, may be switched on and actively cool the electronic device 112.

[0019] Fig. Figure 1b schematically shows another example of the overtemperature detection circuit 110. To a large extent, the Fig. 1b shown overtemperature detection circuit 110 of the in Fig. 1a shown overtemperature detection circuit 110. Thus, for the description of Fig. 1b is largely based on the description of Fig. 1a. As in Fig. 1b and as already stated, the electronic device 112 may be only a part of the circuit board 114 and may not necessarily comprise the entire circuit board 114. Thus, the electronic device 112 may, for example, be or comprise the semiconductor die 118 on the circuit board 114. The temperature sensor 126 may be located on the semiconductor die 114 and may thus measure a temperature on the semiconductor die 118. However, a temperature on the semiconductor die 118 may be at least similar to a temperature on the package 120, on the solder 122, or on a part of the circuit board 114 surrounding the semiconductor die 118. As stated, the temperature threshold may, for example, be tailored to these components, which may be less temperature-resistant compared to the semiconductor die 118, but which can withstand higher temperatures, at least for a short period of time. Fig. As further shown in Figure 1b, the overtemperature detection circuit 110 may also be located on a circuit board 114, and in particular on the same circuit board 114 as the electronic device 112.

[0020] Fig. 2a to Fig. 2c schematically show examples of the evaluation circuit 132 of the overtemperature detection circuit 110. As stated, the evaluation circuit 132 is configured to evaluate a time of temperature exceedance and to declare an overtemperature condition of the electronic device 112 if the time of temperature exceedance exceeds a time threshold. Thus, the evaluation circuit 132 may receive an input signal from the temperature comparator 130 and send an output signal to the electronic device 112. Additionally or alternatively, the evaluation circuit 132 may send an output signal to another component, e.g., to a cooling element separate from the electronic device 112. As also already stated, the evaluation circuit 132 may be an analog or a digital circuit. Thus, the evaluation circuit 132 may include analog or digital components, which are described below.In general, a variety of different options for implementing the evaluation circuit 132 can be conceivable.

[0021] How Fig. As shown in Figure 2a, the evaluation circuit 132 may, for example, be or include a time filter 134. The time filter 134 may be configured to filter out a time of temperature exceedance below the time threshold. Again, the time filter 134 may be implemented in various ways. Thus, the time filter 134 may be a digital or an analog component. As shown in Fig. As shown in Figure 2a, the time filter 134 may include resistors 136 and a capacitor 138 forming a resistor-capacitor circuit. A time constant of the resistor-capacitor circuit may relate to a charging time of the capacitor 138 and may be determined by a product of the resistance and the capacitance. The evaluation circuit 132, in Fig. 2a, in particular the time filter 134, may further include a time comparator 140. The time comparator 140 may be configured to compare the time of the temperature exceedance with the time threshold. The time comparator 140 may be or include an electronic circuit configured to compare two voltages. A first voltage may relate to the time threshold. A second voltage may relate to the time of the temperature exceedance indicated by the temperature comparator 130. An output of the time comparator 140 may indicate which voltage is higher and thus whether the time of the temperature exceedance is higher than the time threshold. Thus, the time comparator 130 may indicate whether the time of the temperature exceedance is greater than the time threshold, which may be displayed to the electronic device 112.

[0022] However, as stated, other options for implementing the evaluation circuit 132 may also be possible. Fig. As shown in Figure 2b, the evaluation circuit 132 may also include a timer 142. Thus, the timer 142 may be started when the temperature comparator 130 indicates a temperature overshoot. The timer 142 may, for example, be or include a counter, in particular an up-counter. The timer 142 may have a clock input. Thus, the timer 142 may be configured to monitor the time of the temperature overshoot, which may be transmitted to the time comparator 140. Once the time period exceeds the time threshold, the time comparator 140 may indicate the overtemperature condition to the electronic device 112.

[0023] Furthermore, as already explained, a time integral over the temperature can also be observed. Thus, as in Fig. 2c, the evaluation circuit 132 may also include an integrator 144. The integrator 144 may be configured to integrate the temperature over time, such as by integrating an incoming temperature signal over time, as long as the temperature comparator 130 indicates a temperature overshoot. Thus, for example, the temperature comparator 130 may trigger a switching element 146 to pass the temperature signal to the integrator 140. As one example, the switching element 146 may be a transistor such as a metal-oxide-semiconductor field-effect transistor, and the temperature comparator 130 may be connected to a gate of the metal-oxide-semiconductor field-effect transistor to turn the metal-oxide-semiconductor field-effect transistor on and off. The integrator 144 may then transmit the integrated temperature signal to the time comparator 140 to compare it with the time threshold.As stated, the time threshold can also be a function of temperature, and in particular, a time integral of the temperature. Thus, the time threshold can also be a time integral threshold. As soon as the time comparator 140 indicates that the time integral threshold has been exceeded, this can be signaled again to the electronic device 112.

[0024] Fig. 3 schematically shows another example of the overtemperature detection circuit 110. To a large extent, the Fig. 3 shown overtemperature detection circuit 110 of the in Fig. 1a shown overtemperature detection circuit 110. Thus, for the description of Fig. 3 largely on the description of Fig. 1a. As in Fig. 3, the overtemperature detection circuit 110 may, in particular, include a further temperature comparator 148. The further temperature comparator 148 may be configured to compare the temperature with a further temperature threshold. For example, the further temperature comparator 148 may be of the same type as the temperature comparator 130, but with a further temperature threshold as input, which may differ from the temperature threshold of the temperature comparator 130. In particular, the further temperature threshold of the further temperature comparator 148 may be higher than the temperature threshold of the temperature comparator 130.

[0025] The further temperature threshold may also be tailored to at least one material included in the electronic device 112, or more precisely to a temperature resistance of the material. In particular, the further temperature threshold may be tailored to a material with a high temperature resistance or even to a most temperature-resistant material of the electronic device 112. As an example, the further temperature threshold may be tailored to the semiconductor die 118, or more precisely to a temperature resistance of the semiconductor die 118. However, other options may also be possible. The electronic device 112 may, for example, further comprise a wire, a conductive trace, a lead frame, a copper tab, or a clip, and the further temperature threshold may be tailored to such a component.Thus, the additional temperature threshold can be tailored to a material selected from the group consisting of a semiconductor, a metal, and a ceramic. The semiconductor can be, in particular, silicon, silicon carbide, or gallium nitride. Other options are, of course, also conceivable.

[0026] The further temperature threshold may be predetermined. Thus, the further temperature threshold may be a predetermined temperature value or a corresponding voltage value applied to the further temperature comparator 148. As an example, the further temperature threshold may be in a range from 100°C to 400°C, in particular from 150°C to 300°C, more specifically from 170°C to 200°C. As a specific example, the further temperature threshold may be 175°C. Such temperatures can damage the aforementioned materials, especially if they are applied only for a short period of time.Unlike the temperature threshold applied to temperature comparator 130, the additional temperature threshold applied to additional threshold comparator 148 can trigger, either independently of time or immediately, the declaration of the overtemperature condition and the initiation of a corresponding response, such as turning off electronic device 112. Thus, the additional temperature threshold can be a maximum temperature value that a temperature at electronic device 112 should not exceed, especially not even for a short period of time.

[0027] The evaluation circuit 132 may be configured to declare the overtemperature condition of the electronic device 112 independently of time or immediately when the further temperature threshold is exceeded. Fig. 3 shows, the evaluation circuit 132 can, for example, comprise a time filter 134 and a logic gate 150. The time filter 134 can be connected to the temperature comparator 130 to filter out times when the temperature exceeds the set time threshold, as described above. However, the evaluation circuit 132 can, in principle, also be implemented differently, such as using the timer 142 instead of the time filter 134, as also described above. However, the further temperature comparator 148 can, in particular, not be connected to such an element. Instead, the further temperature comparator 148 can be connected directly to the logic gate 150. The logic gate 150 can, in particular, be an OR gate or an XOR gate.Thus, if the further temperature comparator 148 indicates that a temperature at the electronic device 112 exceeds the further temperature threshold, a remedial action can be initiated directly, such as turning off the electronic device 112. However, if the temperature comparator 130 indicates that a temperature at the electronic device 112 only exceeds the temperature threshold, which may be lower, in particular compared to the further temperature threshold, such a response cannot be initiated directly. In this case, the response can only be initiated if the electronic device 112 remains at such a temperature for a longer period of time compared to the given time threshold.

[0028] Fig. 4 shows a flow diagram of an example of a method for overtemperature protection. The method comprises the following steps. The method steps shown can be performed in the specified order. However, it should be noted that a different order may also be possible. The method may comprise further method steps that are not listed. Furthermore, one or more of the method steps can be performed once or repeatedly. Furthermore, two or more of the method steps can be performed simultaneously or with an overlap in time. The method can be at least partially computer-implemented. Thus, one or more of the following method steps can be computer-implemented. a) (designated with reference numeral 152) monitoring a temperature of at least a portion of the electronic device 112; b) (identified by reference numeral 154) begin monitoring a temperature overshoot time when the temperature exceeds a temperature threshold; and c) (labeled 156) Declaring an over-temperature condition of the electronic device 112 when the time of the temperature over-exceedance exceeds a time threshold.

[0029] The method may further comprise the following steps: d) (denoted by reference numeral 158) declaring an overtemperature condition of the electronic device 112 when the temperature exceeds a further temperature threshold; and e) (indicated by reference numeral 160) initiating a response to the over-temperature condition when an over-temperature condition of the electronic device 112 is declared.

[0030] As already explained in more detail above, the time threshold may be a function of temperature. The function may be or include an integral of the temperature over time. Furthermore, the time threshold may be an individual time threshold or an accumulated threshold. As an example, the time threshold may be in a range from 1 ms to 100 h, in particular from 10 ms to 1 min, more precisely from 100 ms to 10 s. The temperature threshold may be tailored to at least one material included in the electronic device 112, or more precisely to a temperature resistance of the material. In particular, the temperature threshold may be tailored to a material with a low temperature resistance or even to a least temperature-resistant material of the electronic device 112.As an example, the electronic device 112 may include a component selected from the group consisting of: a circuit board or at least a portion thereof; a housing; a casing; and a solder. The temperature threshold may be tailored to the component. The component may include at least one of a synthetic material, a molded resin, and a composite material, particularly of the FR4 class. As an example, the temperature threshold may be in a range from 80°C to 270°C, particularly from 100°C to 200°C, more specifically from 130°C to 175°C. As a specific example, the temperature threshold may be 135°C.

[0031] The further temperature threshold referred to in step d) may, in particular, be higher than the temperature threshold referred to in step b). Step d) may comprise declaring the overtemperature state of the electronic device independently of time or immediately. The further temperature threshold may also be tailored to at least one material included in the electronic device 112, or more precisely to a temperature resistance of the material. In particular, the further temperature threshold may be tailored to a material with a high temperature resistance or to a most temperature-resistant material of the electronic device 112. As an example, the electronic device 112 may comprise at least one further component selected from the group consisting of: a semiconductor chip; a wire; a conductive track; a lead frame; a copper tab; and a clip.The further temperature threshold can be tailored to the further component. The further component can comprise at least one of a semiconductor, in particular silicon, silicon carbide, gallium nitride; a metal; and a ceramic. As an example, the further temperature threshold can be in a range from 100°C to 400°C, in particular from 150°C to 300°C, more precisely from 170°C to 200°C. As a specific example, the further temperature threshold can be 175°C. The reaction in step e) can comprise triggering a safe state of the electronic device 112. The safe state can be an off state of the electronic device 112. Additionally or alternatively, the reaction can comprise activating cooling of the electronic device 112.

[0032] For further details, please refer to the descriptions of Fig. 1 a to Fig. 3 above.

[0033] The described method or the overtemperature detection circuit 110 can be used in particular for an automotive application. As stated, the electronic device 112 can be configured in particular to control an automotive application, e.g., an engine. Thus, the method or the overtemperature detection circuit 110 can be used in particular for overtemperature detection or overtemperature protection of an automotive application or within an automotive application. Of course, other applications are also possible in general.

[0034] In addition to the examples described above, the following examples are disclosed here: Example 1: A method for over-temperature protection of an electronic device, the method comprising: a) monitoring a temperature of at least a part of the electronic device; b) start monitoring a temperature overshoot time when the temperature exceeds a temperature threshold; and c) Declaring an over-temperature condition of the electronic device when the temperature over-temperature time exceeds a time threshold. Example 2: The method of the previous example, where the time threshold is a function of temperature. Example 3: The method of the previous example, where the function comprises an integral of temperature over time. Example 4: The method of any preceding example, wherein the time threshold is an individual time threshold. Example 5: The method of any preceding example, wherein the time threshold is an accumulated time threshold. Example 6: The method according to any one of the preceding examples, wherein the time threshold value is in a range from 1 ms to 100 h, in particular from 10 ms to 1 min, more precisely from 100 ms to 10 s. Example 7: The method of any preceding example, wherein the temperature threshold is tailored to at least one material included in the electronic device. Example 8: The method of any preceding example, wherein the temperature threshold is matched to a least temperature-resistant material of the electronic device. Example 9: The method of any preceding example, wherein the electronic device comprises a component selected from the group consisting of: a circuit board or at least a portion thereof; a housing; a casing; and a solder. Example 10: The method according to the previous example, where the temperature threshold is tailored to the component. Example 11: The method according to any one of the two preceding examples, wherein the component comprises at least one of a synthetic material; a molding resin; and a composite material, in particular of the FR4 class. Example 12: The method according to any one of the preceding examples, wherein the temperature threshold is in a range from 80°C to 270°C, in particular from 100°C to 200°C, more precisely from 130°C to 175°C. Example 13: The method of any preceding example, wherein the temperature threshold is 135°C. Example 14: The method according to any one of the preceding examples, further comprising: d) Declaring an over-temperature condition of the electronic device when the temperature exceeds another temperature threshold. Example 15: The method according to the preceding example, wherein the further temperature threshold referred to in step d) is higher than the temperature threshold referred to in step b). Example 16: The method according to one of the two preceding examples, wherein step d) comprises the time-independent declaration of the overtemperature condition of the electronic device. Example 17: The method of any one of the three preceding examples, wherein the further temperature threshold is tailored to at least one material included in the electronic device. Example 18: The method according to any one of the four preceding examples, wherein the further temperature threshold is matched to a most temperature-resistant material of the electronic device. Example 19: The method of any of the five preceding examples, wherein the electronic device comprises at least one further component selected from the group consisting of: a semiconductor chip; a wire; a conductive trace; a lead frame; a copper tab; a clip. Example 20: The method according to the previous example, wherein the further temperature threshold is matched to the further component. Example 21: The method according to one of the two preceding examples, wherein the further component comprises at least one of a semiconductor, in particular silicon, silicon carbide, gallium nitride; a metal; and a ceramic. Example 22: The method according to any one of the eight preceding examples, wherein the further temperature threshold value is in a range from 100°C to 400°C, in particular from 150°C to 300°C, more precisely from 170°C to 200°C. Example 23: The method of any of the nine preceding examples, wherein the further temperature threshold is 175°C. Example 24: The method of any preceding example, further comprising: e) initiating a response to the over-temperature condition when an over-temperature condition of the electronic device is declared. Example 25: The method of the preceding example, wherein the response comprises initiating a secure state of the electronic device. Example 26: The method of the preceding example, wherein the secure state is an off state of the electronic device. Example 27: The method of any one of the three preceding examples, wherein the reaction comprises activating cooling of the electronic device. Example 28: The method according to any one of the preceding examples, wherein the electronic device is configured to directly or indirectly control an application, in particular an automotive application, in particular a motor or a light-emitting diode. Example 29: The method of any preceding example, wherein the electronic device is a semiconductor device. Example 30: The method of any preceding example, wherein the electronic device comprises an integrated circuit. Example 31: The method of any preceding example, wherein the method is at least partially computer-implemented. Example 32: An overtemperature detection circuit comprising: • a temperature comparator configured to receive a temperature signal relating to a temperature of at least a portion of an electronic device and to compare the temperature with a temperature threshold; and • an evaluation circuit configured to evaluate a time of temperature overshoot and to declare an overtemperature condition of the electronic device when the time of temperature overshoot exceeds a time threshold. Example 33: The overtemperature detection circuit according to the preceding example, wherein the overtemperature detection circuit is configured to perform a method for overtemperature protection of an electronic device according to any of the preceding method examples. Example 34: The overtemperature detection circuit according to any one of the preceding examples relating to an overtemperature detection circuit, wherein the evaluation circuit comprises a time filter configured to filter out a time of the temperature exceedance below the time threshold. Example 35: The overtemperature detection circuit according to any one of the preceding examples relating to an overtemperature detection circuit, wherein the evaluation circuit comprises a timer configured to monitor a time of the temperature exceedance. Example 36: The overtemperature detection circuit according to any one of the preceding examples relating to an overtemperature detection circuit, wherein the evaluation circuit comprises a time comparator configured to compare the time of the temperature exceedance with the time threshold. Example 37: The overtemperature detection circuit according to any one of the preceding examples relating to an overtemperature detection circuit, wherein the evaluation circuit comprises an integrator configured to integrate the temperature over time. Example 38: The overtemperature detection circuit according to any one of the preceding examples relating to an overtemperature detection circuit, further comprising: • another temperature comparator configured to compare the temperature with another temperature threshold. Example 39: The overtemperature detection circuit according to the preceding example, wherein the evaluation circuit is configured to declare the overtemperature condition of the electronic device in a time-independent manner when the further temperature threshold is exceeded. Example 40: The overtemperature detection circuit according to any one of the preceding examples relating to an overtemperature detection circuit, further comprising: • at least one temperature sensor configured to monitor the temperature of the electronic device or at least a part thereof and to send a corresponding temperature signal. Example 41: The overtemperature detection circuit according to the previous example, wherein the temperature sensor is located on the electronic device. Example 42: The overtemperature detection circuit according to any one of the preceding examples relating to an overtemperature detection circuit, wherein the evaluation circuit is further configured to output the overtemperature condition to the electronic device. Example 43: The overtemperature detection circuit according to the preceding example, wherein the evaluation circuit is further configured to initiate a response to the overtemperature condition. Example 44: The overtemperature detection circuit according to any one of the preceding examples relating to an overtemperature detection circuit, wherein the temperature signal is an analog temperature signal, the overtemperature detection circuit further comprising: • an analog-to-digital converter configured to convert the analog temperature signal into a digital temperature signal. Example 45: The overtemperature detection circuit according to any one of the preceding examples relating to an overtemperature detection circuit, wherein at least one of the temperature comparator, the evaluation circuit and optionally the further temperature comparator is a digital component. Example 46: The overtemperature detection circuit according to any one of the preceding examples relating to an overtemperature detection circuit, wherein the overtemperature detection circuit comprises an integrated circuit. Example 47: A use for an automotive application of at least one of a method for overtemperature protection according to any one of the preceding method examples and an overtemperature detection circuit according to any one of the preceding examples relating to an overtemperature detection circuit.

[0035] Although specific examples have been illustrated and described herein, those skilled in the art will recognize that a variety of alternative and / or equivalent implementations may be substituted for the specific examples shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific examples discussed herein. Therefore, this disclosure is intended to be limited only by the claims and their equivalents.

[0036] It should be noted that the methods and devices, including their preferred embodiments, as set forth in this document can be used independently or in combination with the other methods and devices disclosed in this document. Furthermore, the features set forth in the context of a device are also applicable to a corresponding method, and vice versa. Furthermore, all aspects of the methods and devices set forth in this document can be combined in any way. In particular, the features of the claims can be combined with one another in any way.

[0037] It should be noted that the description and drawings merely illustrate the principles of the proposed methods and systems. Those skilled in the art will be able to implement various arrangements that, although not expressly described or shown herein, embody the principles of the disclosure and are included within its spirit and scope. Furthermore, all examples and embodiments set forth in this document are primarily intended to be illustrative only to assist the reader in understanding the principles of the proposed methods and systems. Furthermore, all statements herein that provide principles, aspects, and embodiments of the disclosure, as well as specific examples thereof, are intended to include their equivalents.

Claims

[1] A method for over-temperature protection of an electronic device (112), the method comprising: a) monitoring a temperature of at least a portion of the electronic device (112); b) start monitoring a temperature overshoot time when the temperature exceeds a temperature threshold; and c) declaring an over-temperature condition of the electronic device (112) when the time of the temperature over-exceedance exceeds a time threshold. [2] The method according to the preceding claim, wherein the time threshold is a function of temperature. [3] The method according to the preceding claim, wherein the function comprises an integral of the temperature over time. [4] The method according to any one of the preceding claims, wherein the time threshold is an accumulated time threshold. [5] The method according to any one of the preceding claims, wherein the temperature threshold is matched to a least temperature-resistant material of the electronic device (112). [6] The method according to any one of the preceding claims, further comprising: d) declaring an over-temperature condition of the electronic device (112) when the temperature exceeds a further temperature threshold. [7] The method according to the preceding claim, wherein step d) comprises declaring the over-temperature condition of the electronic device in a time-independent manner. [8] The method according to one of the two preceding claims, wherein the further temperature threshold is matched to a most temperature-resistant material of the electronic device (112). [9] The method according to any one of the preceding claims, further comprising: e) initiating a response to the over-temperature condition when an over-temperature condition of the electronic device is declared. [10] The method of the preceding claim, wherein the response comprises initiating a secure state of the electronic device (112). [11] The method of any one of the two preceding claims, wherein the response comprises activating cooling of the electronic device (112). [12] An overtemperature detection circuit comprising (110): • a temperature comparator (130) configured to receive a temperature signal relating to a temperature of at least a portion of an electronic device (112) and to compare the temperature with a temperature threshold; and • an evaluation circuit (132) configured to evaluate a time of temperature exceedance and to declare an overtemperature condition of the electronic device (112) when the time of temperature exceedance exceeds a time threshold. [13] The overtemperature detection circuit (110) according to any one of the preceding claims relating to an overtemperature detection circuit (110), wherein the evaluation circuit (132) comprises a time filter (134) configured to filter out a time of temperature exceedance below the time threshold. [14] The overtemperature detection circuit (110) according to any one of the preceding claims relating to an overtemperature detection circuit (110), wherein the evaluation circuit (132) comprises a timer (142) configured to monitor a time of temperature overshoot. [15] The overtemperature detection circuit (110) according to any one of the preceding claims relating to an overtemperature detection circuit (110), wherein the evaluation circuit comprises a time comparator (140) configured to compare the time of the temperature exceedance with the time threshold. [16] The overtemperature detection circuit (110) according to any one of the preceding claims relating to an overtemperature detection circuit (110), wherein the evaluation circuit (132) comprises an integrator (144) configured to integrate the temperature over time. [17] The overtemperature detection circuit (110) according to any one of the preceding claims relating to an overtemperature detection circuit (110), further comprising: • another temperature comparator (148) configured to compare the temperature with another temperature threshold. [18] The overtemperature detection circuit (110) according to any one of the preceding claims relating to an overtemperature detection circuit (110), further comprising: • at least one temperature sensor (126) configured to monitor the temperature of the electronic device (112) or at least a portion thereof and to send a corresponding temperature signal. [19] The overtemperature detection circuit (110) according to any one of the preceding claims relating to an overtemperature detection circuit (110), wherein the temperature signal is an analog temperature signal, the overtemperature detection circuit (110) further comprising: • an analog-to-digital converter (128) configured to convert the analog temperature signal into a digital temperature signal. [20] A use for an automotive application of at least one of a method for over-temperature protection according to any one of the preceding method claims and an over-temperature detection circuit according to any one of the preceding claims relating to an over-temperature detection circuit.

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