Abstract: A safe external A/C adapter protecting the user against hazardous, high-voltage D/C output. High voltage is defined as any voltage in excess of 60V D/C. The adapter provides an internal remote ON/OFF circuit that automatically switches the D/C output OFF unless the output plug is seated within a mating socket disposed in an electronic device powered by the adapter. When the output plug is so seated, the hazardous voltage output is inaccessible to the user. In addition, a secondary shutdown circuit is provided that latches off the A/C input in the unlikely event that the remote ON/OFF circuit should fail. The secondary shutdown circuit is largely independent from the primary remote ON/OFF circuit, and can be implemented using control circuitry already present in the adapter. No special mechanical connectors are required.

Abstract: A method for controlling the output of electrical consumers connected to ac voltage, especially ohmic loads such as hot-plates, fans, hot-air blowers, electric heaters and the like, wherein an electric or electronic circuit component which conducts ac voltage in both directions, preferably a triac, is connected in series with the consumer, and the output control is effected at the consumer by the given angle of the phase control. An additional electric or electronic circuit component is arranged in parallel to the first series switching element, however, the additional component is controlled first so as to conduct in a controlled manner at the trigger time determined by the device control. The current flow of the additional component is substantially taken over by the first circuit component at the latest when reaching a predetermined threshold current through the load or a threshold voltage at the load or triac.

Abstract: A proximity detector having a power switch 30 which is switched as a function of the approach of an object. The detector includes a MOS depletion transistor T1 which connects one of the terminals 15 of the detector to a control input of a power switch 30 through a control switch T2. A regulator stage 45 is coupled to T1 in order to keep T1 saturated in the closed condition of the detector and to regulate the gate voltage of T1 when the detector is in a open state.