Activate by clicking the switch

Function

As already seen in the seven-segment display, one can address the individual light segments through suitable resistances. As a rule however, not the the minus-, but the plus poles are combined. The IC7447 is added, which reduces the number of switches. Through the switching logic in the IC, the numerals are directly displayed.

Using four switches, 16 (0-15) various combinations are possible, which is more than can be indicated. Therefore, the last 5 situations only display symbols. In the above simulation (to cause less confusion) they are simply switched off. The circuit allows, by the way, with a 5-volt DC current supply, (three 1,5-v batteries placed one after the other) the copying of the seven-segment display DL707 (approx. 2€) and the IC74SN47 (approx 1,5€). The seven-segment display DL707 however, has three plus connections which must all be connected with each other. 04/10