摘要 |
A device for protecting an electronic converter, e.g.for halogen lamps, includes a comparator (10) having an output (Vo) as well as non-inverting (14) and inverting (12) inputs for receiving a first input signal (Vi(P)) indicative of the load applied to the converter and a second input signal (Vref(T°)) indicative of the temperature of the converter. The comparator (10) is in a non-inverting Schmitt-trigger configuration having an input-output characteristic with hysteresis. Consequently, the output (Vo) is switched from a first value (Vol) to a second value (Voh) to switch off the electronic converter as the first input signal (Vi(P)) exceeds a first threshold value (VT1). The output (Vo) is switched back from the second value (Voh) to the first value (Vo1) to restart the electronic converter when the first input signal (Vi(P)) falls below a second threshold value (VT2). The second threshold value (VT2) is lower than the first threshold value (VT1), and both threshold values (VT1, VT2) are a function of the signal (Vref(T°)) indicative of the temperature of the converter. The converter is thus protected against both current overloads and temperature overloads. |