摘要 |
PCT No. PCT/SE86/00161 Sec. 371 Date Dec. 5, 1986 Sec. 102(e) Date Dec. 5, 1986 PCT Filed Apr. 8, 1986 PCT Pub. No. WO86/06223 PCT Pub. Date Oct. 23, 1986.An electronic fuse is intended to be triggered should the current from a load (LA) exceed a predetermined value. The load current is restricted first by a switch in series with the load, the switch being kept in a closed or open state by pulses from a pulse length modulator (PB). The pulse length of the modulator is controlled by a sensing circuit (AK) such that when the load current exceeds the predetermined value, the circuit sends a control signal varying as the load current, so that the closing time of the switch (OM) decreases with increasing load current. After a practically contant time the switch is thereafter set to a permanently open state.
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