WO2018115163A1

WO2018115163A1 - Design concept for an esd-optimised control unit

Info

Publication number: WO2018115163A1
Application number: PCT/EP2017/083890
Authority: WO
Inventors: Alexander Wenk; Michael Pechtold; Joachim Vom Dorp; Matthias Keuten; Jürgen Henniger; Andreas REIF; Christian Zankl; Erwin Wittmann; Marion Gebhardt
Original assignee: Conti Temic Microelectronic Gmbh
Priority date: 2016-12-21
Filing date: 2017-12-20
Publication date: 2018-06-28
Also published as: DE102016225727A1

Abstract

The invention relates to an electronic circuit comprising an ESD protection device (100) for protecting an electronic component (200) against an electrostatic discharge. The circuit comprises a substrate material (110), an electronic component (200) which is applied to the substrate material (110), and an ESD protection device (100) which has an opening (120, 30, 140) through the substrate material (110), said opening being adjacent to the electronic component (200) and allowing the current generated by an electrostatic discharge to be discharged.

Description

description

The invention relates to an electronic circuit with an ESD protection device, a control device, a motor vehicle with a control device and a method for producing an electronic circuit with an ESD protection device. Electrostatic discharges, especially in connection with semiconductor devices, are denoted by the abbreviation ESD (Electrostatic Discharge). Because of the low energy, such electrostatic discharges are harmless to humans, however, the electronic semiconductor devices incorporated into controllers may be susceptible to this.

There are basically two different ESD events to consider: - ESD discharges are delivered directly to a metal conductor (in reality, for example, by the finger of a mechanic, in the ESD test by first touching the conductor with the ESD gun and then the Delivery of the ESD charge).

- ESD discharges are released through the air ("lightning bolts") onto the conductor (reality: loaded fitter's finger approaches a conductor until rollover occurs; ESD test: loaded gun approaches the conductor until rollover)

Both events have different limit values of the maximum voltages to be withstood (usually eg direct discharge eg max 8 kV, eg air discharge max 15 kV). Therefore, it is very important to develop improved design concepts with ESD protection, which can also cover increased customer requirements, eg from 8kV to 18kV discharges. It is the object of the invention to reduce the probability of failure of a control unit.

This object is solved by the features of the independent claims. Further developments of the invention will become apparent from the dependent claims and the following description of embodiments.

A first aspect of the invention relates to an electronic circuit with an ESD protection device for protecting an electronic component against electrostatic discharge, comprising: a carrier material, a component which is applied to the carrier material, an ESD protection device, which is passed through the carrier material which is arranged adjacent to the electronic component and allows a derivation of the current generated by an electrostatic discharge in order to prevent a dissipation of the current through the component.

The ESD protection device according to the present invention may provide that a device on a substrate is protected from electrostatic discharge. Essentially ESD damage can be caused by the momentarily high current from the ESD voltage source through a sensitive component

(Semiconductor) to ground or greater electrical capacity in the control unit arise. This is usually a metallic one

Base plate or the housing. This base plate can be connected in a test case to a return conductor of the ESD gun. On the one hand, electrostatic discharges can be prevented by controlling the wiring conductor guides via appropriate protected plastic geometries are protected so that a direct contact or approach of a charged body is made impossible (eg by tight covers,

Plastic spacer rings around punched grid conductor, u. ä.).

Essentially, the following can be achieved hereby:

Ladder guides can not be directly touched by persons (direct discharge).

The structural design may have a sufficiently large minimum distance between the conductors and the charged bodies.

In order to achieve high ESD protection up to high voltages, it may be necessary to have no wiring conductor exposed to the outside at the control unit. This can e.g. be achieved by the use of flexible conductor foils, covers / lids, which are tight (welded / laminated). Existing electrically conductive geometries of the

Controllers can be used as a "lightning arrester" for the ESD flash to direct the discharge current past the sensitive devices directly into the ground return The ground return can be, for example, the base of the circuit, a metal bracket or the housing of a controller protection apparatus can be realized by means of passages in the carrier material in the vicinity of the protected electronic device. the support material with the electronic component can be guided over the ground return conductor or the electronic component can be mounted on the mass ^¬ return conductor. If a problem occurs electrostatic finishing charge The resulting current can be passed directly from the source of the electrostatic discharge in the ground return, through the substrate through the electronic component to be protected is not affected by an electrostatic discharge. That is, no high current is conducted into the electronic component and the electronic component is not damaged.

The ground returns can i.a. be used for stiffening support plates made of aluminum, steel or printed circuit board material with printed conductors. Care should be taken that an approaching, electrically charged body is more likely to discharge into a ground conductor (e.g., base plate or annular open ground wire around a sensitive device) rather than a signal line to be protected which is connected to a sensitive electronic device. It may be the case that ESD-damaged components retain their full function for the time being. The failure of the components can then occur in an uncertain period of time, since the ESD damaged components are no longer suitable for a continuous load.

For the ESD protection device according to the present invention, no additional components need to be installed in the control unit. The already existing components can be designed geometrically different. As a result, additional costs and effort in the production can be avoided. For this purpose, a passage or a plurality of feedthroughs is introduced into the carrier material of the electronic component to be protected. The feedthroughs should be placed adjacent to the electronic component to be protected. The carrier material with the feedthroughs and the electronic component can be arranged above a ground return, eg a conductive base plate or the housing. In the case of an electrostatic discharge, the current can be conducted through the feedthrough into the earth return, so that no high currents are introduced into the electronic component.

The electronic components to be protected can thus be removed from the direct discharge path of the electrostatic discharge and thereby protected.

The increasing ESD requirements in the development of control units can thus be taken into account.

The feedthroughs used in the substrate may have a variety of different shapes. The feedthroughs may be circular holes in the substrate but may also be rectangular, triangular, hexagonal, semi-circular or any other shape. Furthermore, the bushings can also be grooves which are arranged around the component to be protected.

An embodiment of the invention provides that the

Implementation having a conductive via.

The ESD protection device may be used in addition to an electrostatic discharge passage, i. a hole, also provide an electrical feedthrough. That the substrate is pierced by an electrical conductor so that the electrical conductor extends from the top to the bottom of the substrate. By this arrangement, the incoming on the top of the substrate electrostatic discharge can be forwarded directly to the ground return. Thus, the bushings can be designed with small diameters. Furthermore, through the vias, it may be possible to have thicker layers, such as e.g. Circuit boards, with the

To equip and effectively protect ESD protection devices. A further embodiment of the invention provides that the conductive via has an elevation, for example in the form of a tip, out of the plane of the carrier material.

Through the tip, the electrostatic discharge current can be given a point of attack so that the flash of the discharge is "attracted" by the metallized tip and introduced directly into the ground return.

An embodiment of the invention provides that a plurality of feedthroughs are provided in the carrier material, adjacent to the electronic component.

For ESD protection of an electronic component, a multiplicity of feedthroughs can be provided in the carrier material. In this case, the bushings may be holes, metallic bushings or metal bushings with a tip. The individual feedthroughs can be arranged adjacent to the device to be protected in order to ensure the best possible ESD protection. It is also possible to combine the different types of feedthroughs in an ESD protection device to combine the advantages of each type of feedthrough.

An embodiment of the invention provides that the

Bushings are arranged equidistant from each other.

The bushings in the carrier material can have the same distance from each other. Thus, a regular pattern may arise and sufficient capacity remains in the substrate to integrate electrical leads. It should be noted at this point that the number of penetrations can have ^¬ also different distances between them. In particular, so particularly sensitive or provide more intensive ESD protection to important parts by placing more feedthroughs or bushings closer together and closer to the electronic device to be protected.

Another embodiment of the invention provides that the bushings are arranged equidistant from the electronic component to be protected.

In addition to an equidistant arrangement of the bushings with each other, the bushings can also all have a constant distance from the electronic component to be protected. As a result, a geometry can be achieved, which protects all sides of the protected component to the same extent. Again, it should be noted that the bushings may have different distances to the electronic component. In particular in the area with many electrical supply lines to the electronic component, a plurality of feedthroughs may be provided for ESD protection, so that they are particularly protected so as to prevent an increased current in the supply line to the electronic component and thus the damage of the electronic component.

An embodiment of the invention provides that the

Completations are arranged completely or partially around the electronic component to be protected around.

For the ESD protection of an electronic component of different angles of attack, the bushings can be arranged around the electronic component to be protected. Again, the bushings can be arranged equidistant from each other and / or equidistant from the component to be protected. An embodiment of the invention provides that a

Implementation is arranged equidistant to two electronic components. In addition to the equidistant distribution of the bushings among themselves and the equidistant distribution of the bushings to the electronic component to be protected, a bushing can be arranged equidistant to two electronic components to be protected, i. the bushing is located between two components and can simultaneously protect both components against electrostatic discharge.

According to a further embodiment of the invention, the distances between the component to be protected and the

Implementations be different or be varied freely. The distances can be adjusted depending on the component to be protected and the potential hazard at this point, so you can respond to various scenarios. An embodiment of the invention provides that the carrier material is a flexible guide foil.

In order to adapt the support material to the ground return or Lei ^¬ terplatte, the substrate may be a flexible printed circuit film. This can be easily adapted to the surface of the respective ground return, regardless of whether it is a base plate, a conductive holder or a housing. A further aspect of the invention relates to a control device with an electrical described above and below

Circuit for protecting electronic components against electrostatic discharge. Another aspect of the invention relates to a vehicle with a control device described above and below.

The term vehicle is not limited to a car alone, but also includes trucks, buses, tractors, tanks, construction machinery, rail vehicles, ships, aircraft such as helicopters or aircraft, bicycles and motorcycles.

Another aspect of the invention relates to a method of making an electrical circuit for protecting electronic components from electrostatic discharge. In this case, a leadthrough is produced by a carrier material which is arranged adjacent to the electronic component to be protected and makes it possible to dissipate the current generated by an electrostatic discharge in order to prevent the current from being conducted through the component.

The method may provide that at least one feedthrough, e.g. a hole or via, is placed in a substrate such that an electrostatic discharge is passed through the passage, through the substrate, to a mass return. As a result, the electronic components can be protected against overvoltage damage by electrostatic discharges.

Further features, advantages and possible applications of the invention will become apparent from the following description of the embodiments and figures. The figures are schematic and not to scale. If the same reference numerals are given in the following description in different figures, these designate the same or similar elements. Fig. 1 shows a schematic representation of a

ESD protection device with a bushing according to an embodiment of the invention. Fig. 2 shows a schematic representation of a

ESD protection device with a metallized leadthrough according to an embodiment of the invention. Fig. 3 shows a schematic representation of a

ESD protection device with a metalized implementation with a tip, according to an embodiment of the invention. Fig. 4 shows a schematic representation of a

An ESD protection device having a leadthrough adjacent to an electronic device according to an embodiment of the invention. Fig. 5 shows a schematic representation of a

An ESD protection device having a leadthrough adjacent to an electronic device according to an embodiment of the invention. shows a schematic representation of a vehicle with a control device with an ESD protection device according to an embodiment of the invention.

FIG. 1 shows a schematic representation of an ESD protection device 100. It has a carrier material 110 and a feedthrough 120, which is arranged adjacent to an electronic component 200. The electronic component 200 is connected to the carrier material 110 and in the carrier ^¬ material 110, the electrical leads for the electronic component 200 run. The carrier material 110 with the feedthrough 120 can be arranged above a ground return. By this arrangement, an electrostatic discharge can discharge directly into the ground return without striking the substrate 110 and damaging the electronic device 200 thereon.

FIG. 2 shows a metallized feedthrough 130 through the carrier material 110. Due to the metallization, the electricity from the electrostatic discharge can be better from the

Top of the substrate 110 through the substrate 110 therethrough and then passed into the Masserückführung. In addition to the better conduction of the current through the substrate 110 through the metallization, the electrostatic discharges are attracted. Thus, a better ESD protection for the electronic components 200 and thus for the entire electrical circuit can be ensured by the ESD protection device 100. Fig. 3 shows a metallized leadthrough 140 with a top formed out of the plane tip. The tip is applied to the metallized leadthrough 140 to reduce the distance between the metallized leadthrough 140 and the object from which the electrostatic discharge originates. An object from which an electrostatic discharge emanates may, for example, be a human finger which mounts or repairs the electrical circuit or a tool for repair. On the other hand, an active point of attack for the current is offered by the metallized feedthrough 140 with a tip.

Fig. 4 shows an electrical circuit with an ESD protection device 100 which is mounted over a holder. The bracket can be made of metal and is earthed in this case. Thus, the holder represents the Masserückführung. The substrate 110 is in Fig. 4 of a flexible film, in which the supply lines for the electronic component 200 are integrated. The passages 120 are executed in FIG. 4 as circular holes and arranged around the component 200 to be protected. The distances between the individual feedthroughs 120 are the same and also the distance between the individual feedthroughs 120 and the component 200 to be protected are designed to be consistent. Furthermore, it is shown in FIG. 4 that a leadthrough 120 is suitable for protecting two electronic components 200, in which the

Implement 120 is disposed between two electronic components 200 to be protected. Ideally, in this case, the feedthrough 120 is arranged such that the distance to both electronic components 200 is the same.

5 shows an electrical circuit with an ESD protection device 100 in a further embodiment. Here, the carrier material 110 is designed as a flexible film and this is arranged around the Masserückführung around. The feedthroughs 120 are placed close to the electronic device 200 to be protected so that effective protection against electrostatic discharges is possible. The electrostatic discharge thus takes place through the leadthrough 120 of the carrier material 110 and is returned via the ground return, so that no high electrical loads occur for the component 200 to be protected. Thus, by the ESD protection device 100 according to the present invention, an electric circuit can be prevented from damages caused by electrostatic discharges.

6 shows a vehicle 600 with a control unit 610, in which an electrical circuit with an ESD protection device 100 is installed.

Claims

claims

An electronic circuit comprising an ESD protection device (100) for protecting an electronic device (200) from electrostatic discharge, comprising:

a substrate (110);

a device (200) mounted on the substrate (110);

an ESD protection device (100) having a leadthrough (120, 130, 140) through the substrate (110) disposed adjacent to the electronic device (200) and allowing dissipation of the current generated by electrostatic discharge To divert the current through the device (200) to prevent.

2. Electronic circuit according to claim 1,

wherein the passage (120) is a hole.

3. Electronic circuit according to one of claims 1 or 2, wherein the passage (130) has a conductive through-connection.

4. Electronic circuit according to claim 3,

wherein the conductive via (140) has a bump.

5. Electronic circuit according to one of the preceding claims,

wherein a plurality of passages (120, 130, 140) in the carrier material (110), adjacent to the electronic ^{component ¬} (200), are provided.

6. Electronic circuit according to claim 5, wherein the passages (120, 130, 140) are arranged equidistant from each other.

7. Electronic circuit according to one of claims 5 and 6, wherein the bushings (120, 130, 140) are arranged equidistant from the electronic component to be protected (200).

8. An electronic circuit according to one of claims 5 to 7, wherein the passages (120, 130, 140) are arranged completely or partially around the electronic component (200) to be protected.

9. Electronic circuit according to one of the preceding claims,

wherein the passage (120, 130, 140) is arranged equidistant from two electronic components (200).

10. Electronic circuit according to one of the preceding claims,

wherein the carrier material (110) is a flexible conductive foil.

11. Control device (610) with an electronic circuit according to one of claims 1 to 10, for the protection of electronic components (200) from electrostatic discharge.

12. vehicle (600) with a control device (610) according to claim 11.

13. A method for producing an electronic circuit, for protecting electronic components from electrostatic

Discharge, comprising the following step:

Creating (601) of a passage through a carrier material, which is arranged adjacent to the electronic ^¬ to be protected electronic device and a derivative of the by allows electrostatic discharge of generated current to prevent leakage of the current through the device.