| 摘要 |
<p>Provided is an electronic device capable of determining that a pre-assumed temperature cycle has passed, and measuring the service life of a device. A service-life-determining unit (1) comprises a sensor element (11), an interposer (12), and a motherboard (13). The sensor element (11) is joined to the interposer (12) and electrically connected therewith. The interposer (12) is bonded to the motherboard (13) and electrically connected therewith. The sensor element (11) and interposer (12) have different linear expansion coefficients; therefore, stress is generated at solder bumps that are connection sites. The distance between a first solder bump (51) and a second solder bump (53) or second solder bump (54) arranged on a widthwise end part of the sensor element (11) is longer than the distance between the second solder bump (53) and the second solder bump (54); therefore, stress is concentrated at the first solder bump (51). If the first solder bump (51) is set so as to rupture in a pre-assumed temperature cycle, the fact that the pre-assumed temperature cycle has passed can be determined, and the service life of a device can be measured.</p> |
