![]() ![]() In the figure, the mechanical switch is connected to a latch. The figure shows that many bounces from "0" to "1" happen when a switch is pressed. What makes this a problem is the speed of the electronic circuits, since contact's vibrations can be confused with (fast) switching. ![]() When a switch is pressed, it briefly vibrates at the contact area, which causes the circuit to be closed and opened many times before the vibration ceased. Read below about contact bounces and how to avoid them by using a latch.Īll mechanical switches exhibit a phenomenon called "contact bounce".Preparation task 2 (done before the lab).Is it possible to say that P and Q are always inverses of each other? Do you have to prohibit some input combination to make the SR-latch valid?.Now identify a, b, P and Q with the variables used in a SR-latch.You should just remove the connections you have made yourself. A weak battery can make your measurements uncertain even if you wired everything right! - Attention! You should never "tear down" the basic connections we made in advance on the breadboard. Please note! Do not have the battery plugged in unnecessarily. Operate DIL switches with a screwdriver tip to change the order of their variables to the one indicated in the table and fill in the output values. Its output value depends not only on the input values, but also on the order in which they change. The latch is not a combinational circuit but a sequential circuit. You can also simulate the circuit with LTSpice on your own computer at home in advance.Ĭonnect the latch on the board using the provided soft cables.(Do not analyze the input combination a= b=0, this you will do at the lab with a real circuit). Try to reason your way to a truth table for the circuit. ![]() NOR-gates are in the chip 7402, choose two gates from the chip and enter their pin-numbers in the figures - it will facilitate the connection work at the lab.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |