US-12626871-B2 - Relay, and method for operating a relay

US12626871B2US 12626871 B2US12626871 B2US 12626871B2US-12626871-B2

Abstract

A relay. The relay includes a housing and a microelectromechanical (MEMS) component having a MEMS switch that can be switched between two stable states. The relay further comprises an application-specific integrated circuit (ASIC) component which, along with the MEMS component, is arranged in the housing. The ASIC component is configured to control the MEMS switch and/or to monitor a functionality of the MEMS switch.

Inventors

Matthew Lewis
Bernd Klein
David Bill
Jochen Reinmuth
Johannes Holger Moeck
Michael Krueger
Seyed Amir Fouad Farshchi Yazdi
Stefan Pinter

Assignees

ROBERT BOSCH GMBH

Dates

Publication Date: 20260512
Application Date: 20221020
Priority Date: 20211103

Claims (16)

1 . A relay, comprising: a housing; a microelectromechanical (MEMS) component including a MEMS switch that can be switched between two stable states; and an application-specific integrated circuit (ASIC) component, which is arranged together with the MEMS component in the housing, wherein the ASIC component is configured to control the MEMS switch and/or monitor a functionality of the MEMS switch, wherein the ASIC component is configured to monitor a relay current through the MEMS switch.
2 . The relay according to claim 1 , wherein the ASIC component is configured as a cap of the MEMS component.
3 . The relay according to claim 1 , wherein the ASIC component is configured to monitor a switching state of the MEMS switch.
4 . The relay according to claim 1 , wherein the ASIC component is configured to monitor a closing voltage and/or opening voltage of the MEMS switch.
5 . The relay according to claim 1 , wherein to monitor the relay current through the MEMS switch, the ASIC component is configured to: monitor a voltage across a shunt resistor of the relay; and ascertain the relay current through the MEMS switch based on the voltage across the shunt resistor.
6 . The relay according to claim 1 , wherein a coil is arranged around conductive traces of the MEMS switch, and wherein to monitor the relay current through the MEMS switch, the ASIC component is configured to: monitor an induced voltage of the coil; and ascertain the relay current through the MEMS switch based on the induced voltage.
7 . The relay according to claim 1 , wherein the ASIC component is configured to monitor a contact resistance of a contact area of electrodes of the MEMS switch.
8 . The relay according to claim 1 , wherein the ASIC component is configured to monitor a switch-on time and/or switch-off time of the MEMS switch.
9 . The relay according to claim 1 , wherein the ASIC component is configured to calculate an expected lifetime of the relay based on the monitored functionality of the MEMS switch.
10 . The relay according to claim 1 , further comprising an electrode for capacitively ascertaining a state of motion of a movable structure of the MEMS switch.
11 . The relay according to claim 1 , wherein the functionality of the MEMS switch monitored by the ASIC component includes a switching delay of the MEMS switch, and wherein the ASIC component is configured to compensate for the switching delay of the MEMS switch and/or to output a signal based on the monitored switching delay of the MEMS switch.
12 . The relay according to claim 1 , wherein the ASIC component includes an interface to output an electrical signal in dependence on the monitored functionality of the MEMS switch.
13 . The relay according to claim 12 , wherein the ASIC component is configured to output an error signal when the monitored functionality of the MEMS switch does not meet predetermined requirements.
14 . A method for operating a relay, wherein the relay includes a microelectromechanical (MEMS) component including a MEMS switch that can be switched between two stable states, and wherein the relay includes an application-specific integrated circuit (ASIC) component arranged together with the MEMS component in a housing, the method comprising: controlling and/or monitoring a functionality of the MEMS switch by the ASIC component, wherein the controlling and/or monitoring includes monitoring, by the ASIC component, a relay current through the MEMS switch.
15 . The method according to claim 14 , wherein monitoring the relay current through the MEMS switch further comprises: monitoring a voltage across a shunt resistor of the relay; and ascertaining the relay current through the MEMS switch based on the voltage across the shunt resistor.
16 . The method according to claim 14 , wherein a coil is arranged around conductive traces of the MEMS switch, and wherein monitoring the relay current through the MEMS switch further comprises: monitoring an induced voltage of the coil; and ascertaining the relay current through the MEMS switch based on the induced voltage.

Description

FIELD The present invention relates to a relay and a method for operating a relay. BACKGROUND INFORMATION A relay is an electrically operated switch. A circuit can be used to switch between a first switching state and a second switching state. For example, electromagnetic changes due to the flow or absence of a current in a coil can cause a mechanical element of the switch to close or open. An exemplary relay is the reed relay, which comprises two electrical contacts, a coil, and a flyback diode. Relays can be designed as microelectromechanical (MEMS) components. An exemplary MEMS relay is described in U.S. Pat. No. 8,378,766 B2. The same processing steps that are used in the production of conventional semiconductor structures can be used in this instance. Mechanical relays typically consist only of passive components without additional intelligent functions, i.e., built-in testing, monitoring, or other functions. However, in many cases it may be useful to monitor the status or state of the relay. This is especially true for particularly critical systems. Further, any mechanical relay wears out slowly over its lifetime, and as it ages, problems can occur. For example, the relay can no longer be switched on or off, the contact resistance can increase to an uncontrollable level, or the relay can switch more slowly due to increased adhesive forces. To the extent that such intelligent functions are needed for monitoring the functionality of the relay, they must be added with external components and devices, which increases system complexity, area, and costs. SUMMARY The present invention provides a relay and a method for operating a relay. Preferred embodiments of the present invention are disclosed herein. According to a first aspect, the present invention accordingly relates to a relay. According to an example embodiment of the present invention, the relay comprises a housing and a microelectromechanical, MEMS, component comprising a MEMS switch that can be switched between two stable states. The relay further comprises an application-specific integrated circuit (ASIC) component which, along with the MEMS component, is arranged in the housing. The ASIC component is configured to control the MEMS switch and/or to monitor a functionality of the MEMS switch. According to a second aspect, the present invention relates to a method for operating a relay, wherein the relay features a housing and a microelectromechanical, MEMS, component comprising a MEMS switch that can be switched between two stable states, and wherein the relay features an application-specific integrated circuit, ASIC, component arranged in the housing together with the MEMS component. According to an example embodiment of the present invention, the MEMS switch is controlled by the ASIC component and/or the ASIC component monitors a functionality of the MEMS switch. An example embodiment of the present invention provides a relay comprising a MEMS component and an ASIC component in a common housing, wherein the evaluation device already present in the ASIC component is used to monitor and/or control the MEMS switch of the MEMS component. This can provide a very compact and cost-effective relay that can also provide intelligent functions for monitoring. By means of the ASIC component, a multitude of intelligent functions can be integrated into the relay at minimal cost. Also, in many cases, more detailed information can be provided because the ASIC component has direct access to all parts of the relay. By using the logic of the ASIC component to control or monitor the relay, it is possible to add the corresponding functionalities with only minimal additional production costs. There is no need for a separate ASIC, which would be significantly more expensive to manufacture. In the following, the term “monitoring” can be understood as measuring, evaluating, or checking a corresponding variable. Furthermore, it is possible to compare the corresponding variable with predefined values in order to ascertain whether or not there is an error with respect to the corresponding variable. A functionality of the MEMS switch can be understood as the ability to switch correctly. Further, various characterizations of the MEMS switch may also be understood hereunder, such as a closing voltage, a relay current, or other features described in particular below. According to another embodiment of the relay of the present invention, the ASIC component is configured as a cap of the MEMS component. By using the ASIC component as a cap, a compact, hermetically sealed relay can be provided with various metallization options. According to a further embodiment of the present invention, the relay comprises (optionally in addition to an electrode for switching the MEMS switch) an electrode for capacitively ascertaining a state of motion of a movable structure (i.e., the element that can be switched) of the MEMS switch. According to another embodiment of the relay of the present i