Accurate and High-Speed Power Module Characteristic Assessment

Abstract

To provide systems and methods for accurate and fast measurement of junction temperature for power modules.SOLUTION: Such systems and methods include one or more power transistors that each have a respective die surface, over which a conductive overlay is positioned and which is electrically coupled to the conductive overlay. A temperature sensor is physically bonded to a top surface of the conductive overlay to provide direct temperature measurement for the one or more power transistors.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] These teachings relate generally to power modules, and more specifically to the measurement of the junction temperature of a power module.

Background Art

[0002] Power modules use transistors to output stable and reliable power for a variety of applications, including use in aircraft and similar high-performance systems. Also, the operation of a power module can generate a significant amount of heat, which can damage the power module if not properly managed and / or result in unreliable operating conditions and power output. Therefore, control circuits are often used to take temperature into account when operating a power module.

Summary of the Invention

Means for Solving the Problems

[0003] Various needs are at least partially satisfied through the provision of an accurate and fast assessment or measurement of the various characteristics of the power module described in the following detailed description, especially when learned in conjunction with the drawings. The complete and implementable disclosure of the aspects of this description, including their best mode, is directed to those of ordinary skill in the art and is described in the following specification, which refers to the accompanying drawings as follows.

Brief Description of the Drawings

[0004]

Figure 1

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DETAILED DESCRIPTION OF THE INVENTION

[0005] Elements in the drawings are illustrated for simplicity and clarity and are not necessarily drawn to scale. For example, dimensions and / or the relative positions of some of the elements in the figures may be emphasized compared to other elements to improve understanding of various embodiments of the present teachings. Also, common but well-known elements that are useful or necessary in commercially viable embodiments are often not depicted so as not to obscure the view of these various embodiments of the present teachings. Specific operations and / or steps may be described or depicted in a particular order of occurrence, but those skilled in the art will understand that such particularity with respect to the order is not actually required.

[0006] A typical power module is assembled from a plurality of transistors having a plurality of surface wire bonds on the die surface for interconnecting the transistors and the control circuit together. Thus, these modules do not provide an area for direct temperature measurement on the die surface. Rather, the module uses alternative temperature measurements from a printed circuit board (PCB) control circuit, including indirect methods such as measurement of the body diode and expensive optical methods. The lack of a simple direct temperature measurement method increases the operating cost and limits reliability and safety.

[0007] Generally speaking, various aspects of the present disclosure can be used with a power module that includes one or more power transistors and a conductive overlay that provides a direct attachment surface for sensors, such as a temperature sensor, that can provide a direct temperature measurement method for each of the one or more power transistors. The conductive overlay can include a clearly defined metallic and stable surface that is directly connected to the power transistor die surface by a short-distance metal connection. The additional surface of the conductive overlay provides high-speed and accurate measurement capabilities and enables the temperature sensor to be positioned on top to improve the reliability of module operation. This sensor can be easily wired to a PCB controller, and the data from the sensor can be provided to a gate board to provide reliable module operation. Direct temperature measurement results in improved reliability and safety when operating the power module.

[0008] The terms and expressions used herein have the ordinary technical meaning given to such terms and expressions by those skilled in the art as described above, unless a different specific meaning is stated herein separately. As used herein, the word "or" will be interpreted to have a disjunctive rather than a conjunctive structure, unless expressly indicated otherwise. Terms such as "coupled," "fixed," "attached to," etc. refer to both direct coupling, fixing, or attachment and indirect coupling, fixing, or attachment through one or more intermediate components or features, unless specifically specified otherwise herein.

[0009] The singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

[0010] As used throughout the specification and claims, approximating language may be applied to modify any quantitative representation that could vary without changing the basic function to which it relates. Accordingly, values modified by terms such as “about,” “approximately,” and “substantially” are not to be limited to the specific value specified. In at least some instances, the approximating language can correspond to the precision of the instrument for measuring the value, or the precision of the method or machine for constructing or manufacturing the component and / or system. For example, the approximating language may refer to being within a margin of 10 percent.

[0011] Upon review and study of the following detailed description, the foregoing and other advantages will become apparent. Referring now to the drawings, and in particular to FIG. 1, a power module 100 is shown. The power module 100 can include a conductive overlay 102 having a temperature sensor 104 adhered or bonded to its upper surface. In some embodiments, the conductive overlay 102 can include a power overlay (POL) of copper or other conductive material sufficient to provide a bonding surface for the temperature sensor 104. Such POL configurations can provide a planar interconnect region where various systems can input and output and external devices can interface with one or more power transistors 108 (see FIG. 2). Examples of POLs that can form the conductive overlay 102 described herein are provided in U.S. Patent No. 10,269,688, which is hereby incorporated by reference in its entirety. However, it will be recognized that the embodiments described herein are also applicable with respect to alternative planar interconnect technologies such as copper clips, multilayer organic PCBs, etc., as well as flip chip and chip-in-polymer technologies.

[0012] Referring to FIG. 2, a partial cross-sectional view of the power module 100 is shown. The power module 100 can further include a thermally conductive epoxy 106 for adhering the temperature sensor 104 to the conductive overlay 102. The thermally conductive epoxy 106 can act as a thermal conduction medium between the upper surface of the conductive overlay 102 and the temperature sensor 104 so that the temperature sensor 104 can obtain a consistent and accurate indication therefrom. The temperature sensor 104 can be attached by the thermally conductive epoxy 106 on a wide, clearly defined, metallic and stable surface of the conductive overlay 102. Further, the position of the temperature sensor 104 can coincide with the position of the highest temperature on the conductive overlay 102. In some embodiments, the position of the highest temperature can be identified by modeling the operation of the power module 100. In some embodiments, the temperature sensor 104 can be attached to the conductive overlay 102 above the center of one of the one or more power transistors 108, which modeling and testing indicate as the hottest location for the power module 100. However, other positions are also contemplated, and it will be recognized that in some embodiments multiple temperature sensors may be located near the same general location.

[0013] The temperature sensor 104 can include a thermocouple and / or a resistance temperature detector having a non-conductive housing.

[0014] Each of the one or more power transistors 108 has a die surface on which the conductive overlay 102 can be located thereon. The power transistor 108 can include a silicon carbide (SiC) MOSFET or a similar power transistor known in the art.

[0015] The non-conductive layer 114 and the adhesive layer 112 can be positioned between the conductive overlay 102 and the one or more power transistors 108. The non-conductive layer 114 can function as a dielectric layer between the respective die surfaces of the power transistors 108 and the conductive overlay 102. The non-conductive layer 114 can include Kapton® or other similar materials.

[0016] Also, the conductive overlay 102 can include vias 110 that electrically couple the conductive overlay 102 to the one or more power transistors 108. In these embodiments, the vias 110 can pass through the non-conductive layer 114 and the adhesive layer 112 to provide a direct metal connection between the conductive overlay 102 and the one or more power transistors 108. Additionally, or alternatively, in some embodiments, one or more sintered layers can be utilized to interconnect the conductive overlay 102 to the surface of the one or more power transistors.

[0017] Referring now to FIG. 3, another schematic view of the power module 100 is shown. As seen in FIG. 3, in some embodiments, the power module 100 can include additional sensors coupled to the conductive overlay 102. The additional sensors can include a plurality of current sensors 116 physically adhered to and electrically coupled to the conductive overlay 102 for measuring the current flow between two of the one or more power transistors 108 or other elements of the power module 100.

[0018] As can be seen in the additional partial cross-sectional view of the power module 100 of FIG. 4, the current sensor 116 can be adhered to the conductive overlay 102 by solder 117 and can bridge the upper part of the gap between sections of the conductive overlay 102. The current sensor 116 can include a current measurement shunt attached to the conductive overlay 102 during the assembly process of the power module 100. The current sensor 116 can be positioned between other current or temperature sensors or between the upper copper sections of the conductive overlay 102 to provide a local current value.

[0019] In some embodiments, the conductive overlay 102 can be spaced a distance from each die surface of the plurality of transistors 108, such that the temperature sensor 104 and / or the plurality of current sensors 116 coupled to the upper surface of the conductive overlay 102 are also spaced the distance from each die surface of the plurality of transistors 108. The vias 110 can bridge the distance to electrically couple the conductive overlay 102 to each of the one or more power transistors 108.

[0020] The distance between the upper surface of the conductive overlay 102 to which the temperature sensor 104 and the solder current sensor 116 are coupled and the upper surface of the power transistor 108 can be approximately 150 μm, where 100 μm of the distance results from the thickness of the conductive overlay 102 and 50 μm of the distance results from the thickness of the vias 110. The short distance between the upper surface of the power transistor 108 and the upper surface of the conductive overlay 102 to which the temperature sensor 104 is coupled improves the accuracy of temperature measurement compared to other indirect temperature measurement methods. In particular, the close distance limits the dissipation of heat before being read by the temperature sensor 104 and / or limits the influence of other heat sources on the temperature value read by the temperature sensor 104, helping to ensure that the temperature indication closely matches the actual temperature of the upper surface of the power transistor 108.

[0021] Here, referring to FIG. 5, another schematic view of the power module 100 is shown. As can be seen in FIG. 5, the temperature sensor 104 and the plurality of current sensors 116 can be electrically coupled to the control circuit 118 via wires and solders 120 and 122, respectively.

[0022] As can be seen in FIG. 6, the control circuit 118 can include a printed circuit board that can be installed within a housing containing the remainder of the power module 100. The control circuit 118 can pass signals to a gate board connected to the control circuit 118 to assist in controlling the operation of one or more power transistors 108.

[0023] The embodiments of the power module 100 shown in FIGS. 1-6 depict two conductive overlays 102 coupled to two groups or sets of one or more power transistors 108, although it will be understood that embodiments having more or fewer conductive overlays 102 are contemplated.

[0024] Here, referring to FIG. 7, the embodiments described herein are also directed to a method 200 for controlling the power module 100 using the control circuit 118. According to step 202 of method 200, the temperature sensor 104 directly measures the surface temperature of the conductive overlay 102 and / or the current sensor 116 measures the current flow. According to step 204 of method 200, the control circuit 118 adjusts the operation of one or more power transistors 108 electrically coupled to the control circuit 118.

[0025] The operation of the power transistor 108 can be adjusted based on either a direct measurement of the surface temperature by the temperature sensor 104 or one or more of the measurements of the current flow from the plurality of current sensors 116. Further, the adjustment of the operation of the power transistor 108 can include stopping the operation of one, a plurality, or all of the one or more power transistors 108 when the direct temperature measurement and / or the current measurement exceeds a preset threshold. Additionally, the adjustment of the operation of the power transistor 108 can include restricting the operation of one, a plurality, or all of the one or more power transistors 108 when the direct temperature measurement and / or the current measurement additionally exceeds an additional preset threshold. The restriction of the operation can include shutting down only some of the one or more power transistors 108 and / or varying the operating parameters such as the switching frequency, input power, etc., so that the temperature and / or current measurement values decrease to a level consistent with the normal safe operation of the power module 100.

[0026] In some embodiments, the current sensors 116 can measure the current in parallel from different locations on the conductive overlay 102. In these embodiments, the incremental difference in the current from each location can be monitored, and when the current value at one location deviates from the other current values by a preset amount, the control circuit 118 can adjust the operation of the power transistor 108 to avoid catastrophic failure. For example, such an adjustment can include shutting down some or all of the operations of the power transistor 108. Also, in some embodiments, the control circuit can shut down only the power transistor connected to the current sensor whose current value has exceeded a preset threshold among the power transistors 108.

[0027] A further aspect of the present invention is provided by the subject matter of the following clauses.

[0028] One or more power transistors, each having its own die surface; a conductive overlay on top of each of the die surfaces of the one or more power transistors, electrically coupled thereto; and a temperature sensor coupled to the upper surface of the conductive overlay to provide direct temperature measurement to the one or more power transistors, a power module.

[0029] The power module according to any one of the preceding items, further comprising a current sensor physically adhered to and electrically coupled to the conductive overlay for measuring the current flow between two of the one or more power transistors.

[0030] The power module according to any one of the preceding items, wherein the current sensor includes a current measurement shunt.

[0031] The power module according to any one of the preceding items, further comprising a control circuit electrically coupled to the one or more power transistors, the temperature sensor, and the current sensor, the control circuit being configured to adjust the operation of the one or more power transistors based on the direct temperature measurement from the temperature sensor and the measurement of the current flow.

[0032] The power module according to any one of the preceding items, wherein the adjustment of the operation of the one or more power transistors includes stopping the operation of the one or more power transistors when at least one of the direct temperature measurement and the measurement of the current flow exceeds a threshold value.

[0033] The power module according to any one of the preceding items, wherein the adjustment of the operation of the one or more power transistors includes restricting the operation of the one or more power transistors when at least one of the direct temperature measurement and the measurement of the current flow exceeds a threshold value.

[0034] The power module according to any one of the preceding items, wherein the one or more power transistors include silicon carbide (SiC) MOSFETs.

[0035] The conductive overlay is separated by a distance from each of the die surfaces of the plurality of transistors, and the conductive overlay includes conductive vias that bridge the distance to electrically couple the conductive overlay to each of the one or more power transistors, the power module according to any of the preceding items.

[0036] The power module according to any of the preceding items, wherein the temperature sensor includes a resistance temperature detector having a non-conductive housing.

[0037] The power module according to any of the preceding items, wherein the temperature sensor is adhered to the conductive overlay by a thermally conductive epoxy.

[0038] The power module according to any of the preceding items, further comprising a control circuit electrically coupled to the one or more power transistors and the temperature sensor, the control circuit being configured to adjust the operation of the one or more power transistors based on the direct temperature measurement from the temperature sensor.

[0039] The power module according to any of the preceding items, wherein the adjustment of the operation of the one or more power transistors includes stopping the operation of the one or more power transistors when the direct temperature measurement exceeds a threshold.

[0040] The power module according to any of the preceding items, wherein the adjustment of the operation of the one or more power transistors includes restricting the operation of the one or more power transistors when the direct temperature measurement exceeds a threshold.

[0041] One or more power transistors, each having its own die surface; a first conductive overlay on top of each of said die surfaces, electrically coupled to a first group of said one or more power transistors; a second conductive overlay on top of each of said die surfaces, electrically coupled to a second group of said one or more power transistors; a first temperature sensor physically adhered to the top surface of said first conductive overlay to provide direct temperature measurement for said first group of said one or more power transistors; a second temperature sensor physically adhered to the top surface of said second conductive overlay to provide direct temperature measurement for said second group of said one or more power transistors; a plurality of current sensors physically adhered to and electrically coupled to said first conductive overlay or said second conductive overlay, each of said plurality of current sensors being configured to measure current flow between two of said one or more power transistors; and a control circuit electrically coupled to said one or more power transistors, said first and second temperature sensors, and said plurality of current sensors, said control circuit being configured to adjust the operation of said one or more power transistors based on said direct temperature measurements from said first and second temperature sensors and said measurements of said current flow from said plurality of current sensors, a power module.

[0042] The power module according to any preceding item, wherein the adjustment of the operation of said one or more power transistors includes stopping the operation of said one or more power transistors when any of said direct temperature measurements exceeds a threshold.

[0043] The power module according to any preceding item, wherein the adjustment of the operation of said one or more power transistors includes restricting the operation of said one or more power transistors when any of said direct temperature measurements exceeds a threshold.

[0044] The power module according to any preceding item, wherein said one or more power transistors include silicon carbide (SiC) MOSFETs.

[0045] The first and second conductive overlays are separated by a distance from respective die surfaces of each of the one or more power transistors, and the first and second conductive overlays include conductive vias bridging the distance to electrically couple the first and second conductive overlays to respective ones of the one or more power transistors, the power module according to any of the preceding items.

[0046] The first and second temperature sensors include resistance temperature detectors having non-conductive housings, the power module according to any of the preceding items.

[0047] Directly measuring a surface temperature of the conductive overlay by a temperature sensor physically adhered to an upper surface of the conductive overlay, the conductive overlay being electrically coupled to one or more power transistors and being above respective die surfaces thereof; and adjusting an operation of the one or more power transistors by a control circuit electrically coupled to the one or more power transistors, the adjustment being based on the direct measurement of the surface temperature, the method comprising.

[0048] The conductive overlay is separated by a distance from respective die surfaces of each of the plurality of transistors, and at least one sintered layer bridges the distance to electrically couple the conductive overlay to respective ones of the one or more power transistors, the power module according to any of the preceding items.

[0049] Forming a conductive overlay on a first surface of one or more power transistors; and coupling a temperature sensor to an upper surface of the conductive overlay, a method of manufacturing a power module.

[0050] The method according to any of the preceding items, further comprising physically and electrically coupling a current sensor to the conductive overlay at a position between two different ones of the one or more power transistors.

[0051] Bonding the non-conductive layer to the first surface of the one or more power transistors via an adhesive layer; and forming the conductive overlay on top of the non-conductive layer having vias extending through the non-conductive layer and the adhesive layer to the first surface of the one or more power transistors, the method according to any of the preceding items further comprising.

[0052] The method according to any of the preceding items further comprising electrically coupling the temperature sensor to a control circuit.

[0053] The conductive overlay is spaced apart from each of the respective die surfaces of the one or more power transistors by a distance, at least one sintered layer bridges the distance, and the conductive overlay is electrically coupled to each of the one or more power transistors, the power module according to any of the preceding items.

[0054] A further aspect of the present invention is provided by the subject matter of the following items.

[0055] [Item 1] One or more power transistors, each having a respective die surface; a conductive overlay over each of the respective die surfaces of the one or more power transistors, electrically coupled to each of the one or more power transistors; and a temperature sensor coupled to the upper surface of the conductive overlay to provide direct temperature measurement to the one or more power transistors, a power module.

[0056] [Item 2] The power module according to any of the preceding items, further comprising a current sensor physically and electrically coupled to the conductive overlay to measure current flow between two of the one or more power transistors.

[0057] [Item 3] The power module according to any of the preceding items, wherein the current sensor includes a current measurement shunt.

[0058] [Item 4] The power module according to any preceding item, further comprising a control circuit electrically coupled to the one or more power transistors, the temperature sensor, and the current sensor, wherein the control circuit is configured to adjust the operation of the one or more power transistors based on the direct temperature measurement from the temperature sensor and the measurement of the current flow.

[0059] [Item 5] The power module according to any preceding item, wherein the adjustment of the operation of the one or more power transistors includes stopping the operation of the one or more power transistors when at least one of the direct temperature measurement and the measurement of the current flow exceeds a threshold value.

[0060] [Item 6] The power module according to any preceding item, wherein the adjustment of the operation of the one or more power transistors includes restricting the operation of the one or more power transistors when at least one of the direct temperature measurement and the measurement of the current flow exceeds a threshold value.

[0061] [Item 7] The power module according to any preceding item, wherein the one or more power transistors include silicon carbide (SiC) MOSFETs.

[0062] [Item 8] The power module according to any preceding item, wherein the conductive overlay is spaced apart from each die surface of the one or more power transistors by a distance, and the conductive overlay includes conductive vias that bridge the distance to electrically couple the conductive overlay to each of the one or more power transistors.

[0063] [Item 9] The power module according to any preceding item, wherein the temperature sensor includes a thermistor having a non-conductive housing.

[0064] [Item 10] The power module according to any preceding item, wherein the temperature sensor is adhered to the conductive overlay by a thermally conductive epoxy.

[0065] [Item 11] The power module according to any of the preceding items, further comprising a control circuit electrically coupled to the one or more power transistors and the temperature sensor, the control circuit being configured to adjust the operation of the one or more power transistors based on the direct temperature measurement from the temperature sensor.

[0066] [Item 12] The power module according to any of the preceding items, wherein the adjustment of the operation of the one or more power transistors includes stopping the operation of the one or more power transistors when the direct temperature measurement exceeds a threshold value.

[0067] [Item 13] The power module according to any of the preceding items, wherein the adjustment of the operation of the one or more power transistors includes restricting the operation of the one or more power transistors when the direct temperature measurement exceeds a threshold value.

[0068] [Item 14] The conductive overlay is separated from each of the die surfaces of the one or more power transistors by a distance, The power module according to any of the preceding items, wherein at least one sintered layer bridges the distance and electrically couples the conductive overlay to each of the one or more power transistors.

[0069] [Item 15] A method comprising: directly measuring a surface temperature of the conductive overlay by a temperature sensor coupled to an upper surface of the conductive overlay, the conductive overlay being electrically coupled to one or more power transistors above their respective die surfaces; and adjusting an operation of the one or more power transistors by a control circuit electrically coupled to the one or more power transistors, the adjustment being based on the direct measurement of the surface temperature.

[0070] [Item 16] forming a conductive overlay on a first surface of one or more power transistors; and coupling a temperature sensor to an upper surface of the conductive overlay, a method of manufacturing a power module.

[0071] [Item 17] further comprising physically and electrically coupling a current sensor to the conductive overlay at a position between two different ones of the one or more power transistors, the method according to any preceding item.

[0072] [Item 18] coupling a non-conductive layer to the first surface of the one or more power transistors via an adhesive layer; and forming the conductive overlay on an upper portion of the non-conductive layer having vias extending to the first surface of the one or more power transistors through the non-conductive layer and the adhesive layer, the method according to any preceding item.

[0073] [Item 19] further comprising electrically coupling the temperature sensor to a control circuit, the method according to any preceding item.

Explanation of Reference Numerals

[0074] 100 Power module 102 Conductive overlay 104 Temperature sensor 106 Thermally conductive epoxy 108 Power transistor 108 Transistor 110 Via 112 Adhesive layer 114 Non-conductive layer 116 Current sensor 118 Control circuit 200 Method 202 Step 204 Step

Claims

1. One or more power transistors, each having its own die surface; A conductive overlay on top of each of the die surfaces of the one or more power transistors, electrically coupled to each of the one or more power transistors; and A temperature sensor coupled to the upper surface of the conductive overlay to provide direct temperature measurement to the one or more power transistors, The conductive overlay is spaced a distance from each of the die surfaces of the one or more power transistors, The conductive overlay includes conductive vias that bridge the distance to electrically couple the conductive overlay to each of the one or more power transistors, a power module.

2. The power module according to claim 1, further comprising a current sensor physically and electrically coupled to the conductive overlay to measure current flow between two of the one or more power transistors.

3. The power module according to claim 2, wherein the current sensor includes a current measurement shunt.

4. The one or more power transistors, the temperature sensor and a control circuit electrically coupled to the current sensor, The control circuit is configured to adjust the operation of the one or more power transistors based on the direct temperature measurement from the temperature sensor and the measurement of the current flow, the power module according to claim 2.

5. Adjusting the operation of the one or more power transistors includes stopping the operation of the one or more power transistors when at least one of the direct temperature measurement and the measurement of the current flow exceeds a threshold, the power module according to claim 4.

6. Adjusting the operation of the one or more power transistors includes restricting the operation of the one or more power transistors when at least one of the direct temperature measurement and the measurement of the current flow exceeds a threshold, the power module according to claim 4.

7. The power module according to claim 1, wherein the one or more power transistors include silicon carbide (SiC) MOSFETs.

8. The power module according to claim 1, wherein the temperature sensor includes a resistance temperature detector having a non-conductive housing.

9. The power module according to claim 1, wherein the temperature sensor is adhered to the conductive overlay by a thermally conductive epoxy.

10. Further comprising a control circuit electrically coupled to the one or more power transistors and the temperature sensor, The control circuit is configured to adjust the operation of the one or more power transistors based on the direct temperature measurement from the temperature sensor, the power module according to claim 1.

11. The power module according to claim 10, wherein adjusting the operation of the one or more power transistors includes stopping the operation of the one or more power transistors when the direct temperature measurement exceeds a threshold.

12. The power module according to claim 10, wherein adjusting the operation of the one or more power transistors includes restricting the operation of the one or more power transistors when the direct temperature measurement exceeds a threshold.

13. One or more power transistors, each having its own die surface; A conductive overlay on top of each of the respective die surfaces of the one or more power transistors, electrically coupled to each of the one or more power transistors; and A temperature sensor coupled to the upper surface of the conductive overlay to provide a direct temperature measurement to the one or more power transistors, The conductive overlay is spaced a distance from each of the respective die surfaces of the one or more power transistors, A power module in which at least one sintered layer bridges the distance and electrically couples the conductive overlay to each of the one or more power transistors.

14. A step of directly measuring the surface temperature of the conductive overlay by a temperature sensor coupled to the upper surface of the conductive overlay, wherein the conductive overlay is electrically coupled to one or more power transistors at the upper part of their respective die surfaces; A step of adjusting the operation of the one or more power transistors by a control circuit electrically coupled to the one or more power transistors, the adjustment being based on the direct measurement of the surface temperature, The conductive overlay is spaced a distance from each of the respective die surfaces of the one or more power transistors, A method, wherein the conductive overlay includes conductive vias bridging the distance to electrically couple the conductive overlay to each of the one or more power transistors.

15. The step of bonding a non-conductive layer to a first surface of one or more power transistors via an adhesive layer; The step of forming a conductive overlay on top of the non-conductive layer having vias extending through the non-conductive layer and the adhesive layer to the first surface of the one or more power transistors; The step of bonding a temperature sensor to the top surface of the conductive overlay, a method for manufacturing a power module.

16. The method according to claim 15, further comprising the step of physically and electrically coupling a current sensor to the conductive overlay at a position between two different ones of the one or more power transistors.

17. The method according to claim 15, further comprising the step of electrically coupling the temperature sensor to a control circuit.

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