| 摘要 |
A trimmable microminiature force-sensitive switching device for detecting the state of external conditions, such as pressure, acceleration and temperature, is disclosed. The device includes a silicon substrate having a reduced-thickness, deflectable member adapted to change its deflection in response to changes in the external condition to be detected. Increasing deflection of the member establishes electrical contact between a common contact and first one, then progressively more, spaced electrical contacts of a plurality of switches. Each of the spaced electrical contacts is connected to a common terminal. Trimming of the switching device is accomplished by application of a preselected external force, such as pressure, that causes the deflection of the deflectable member and the closing of one or more of the switches. Electrical energy is then applied to the external terminal of the common contact and the external terminal of the common terminal of the fusible links, such that current flows through the switches that have closed and through their associated fusible links, causing those fusible links to open circuit, thereby precluding the subsequent detection of external conditions whose level is at or below the preselected level applied during trimming of the device.
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