Selectively energising circuit for antiparallel LEDs - has junction points between anode and cathode of two LEDs coupled to voltage source poles

摘要

The circuit energises one or none of two anti-parallel LEDs. Each of the junction points (3,4) between the anode of one LED (1 or 2) and the cathode of the other LED are coupled via a resistor (5,6) to a pole (7) of a voltage source, and via a semiconductor switch (8,9) selectively high- or low-ohmic to the other pole (12) of the voltage source, according to the switch input level. At the junction point (3) between first LED anode and the second LED cathode is coupled the output of a first controllable switching stage, as well as the input of a second controllable, inverting switching stage. The output of the second switching stage is linked to the LED second junction point (4) via a resistor. USE/ADVANTAGE - For two-colour LEDs, with simple switch and energising circuit for replacement of pole reversed switch.