摘要 |
An apparatus, such as a mobile phone for example, is electronically switched on in the following manner. A power-on circuit (POC) initially provides a power-on signal (POS). A power supply (PWS) derives a power supply voltage (VCC) from an electrical power source (EPS) in response to the power-on signal (POS). A feedback path (FBP) upholds the power-on signal (POS) on the basis of the power supply voltage (VCC). There is a risk that the apparatus is switched off unintentionally when the electrical power source (EPS), a battery for example, is temporarily disconnected from the power supply (PWS) for a relatively short time, for example due to a shock or a vibration. In order to reduce this risk, the feedback path (FPB) comprises a hold circuit (HOLD) for upholding the power-on signal (POS) for a least a period of time (Thold) following a drop (DRP) in the power supply voltage (VCC). |