Low-G MEMS acceleration switch

摘要

A motion-sensitive low-G MEMS acceleration switch, which is a MEMS switch that closes at low-g acceleration (e.g., sensitive to no more than 10 Gs), is proposed. Specifically, the low-G MEMS acceleration switch has a base, a sensor wafer with one or more proofmasses, an open circuit that includes two fixed electrodes, and a contact plate. During acceleration, one or more of the proofmasses move towards the base and connects the two fixed electrodes together, resulting in a closing of the circuit that detects the acceleration. Sensitivity to low-G acceleration is achieved by proper dimensioning of the proofmasses and one or more springs used to support the proofmasses in the switch.

主权项

1. A MEMS acceleration switch, comprising:
a base including a first contact plate; a sensor wafer with a proofmass, wherein the proofmass includes a second contact plate; an open circuit formed by a gap between the first contact plate and the second contact plate; and wherein the proofmass is coupled to the sensor wafer via springs designed so that during acceleration, the proofmass moves towards the base and the first contact plate comes in contact with the second contact; wherein the springs have a 25 to 1 or lower length-to-width ratio.