0
\$\begingroup\$

I have the following plans: I want to use a 555 timer in astable mode to light up 5 different LEDs. These should light up one after the other (i.e. not two at the same time). After that, there should be a pause for the same period of time as for the lighting of an LED. Then, it starts from the beginning again.

I already checked a little today: I need a ring counter. Unfortunately, I don't have one in the library. I'm using PSpice for TI 2020, so I don't have all imaginable parts. Could you suggest how I can use simple means to build a ring counter with 6 outputs? I don't expect you to solve everything, I'm just asking for ideas so that I can start.

I would like to use a typical 9V battery as the source. (If that's too much, I'll just use something smaller or a voltage divider. That shouldn't stop us.)

I can do that with the timer. Did you see in the last thread. How fast can the timer actually get, in terms of frequency?

However, if you have a completely different approach, always give me your opinion! :)

\$\endgroup\$
5
  • 2
    \$\begingroup\$ PSpice isn't going to necessarily provide a pre-assembled Ring Counter, but a ring counter is nothing more than a composition of flipflops and some logic for feedback and pattern generation. The individual parts (flipflops and logic gates) are almost certainly available in a simulator designed for digital tasks. \$\endgroup\$
    – nanofarad
    Nov 8, 2021 at 19:14
  • \$\begingroup\$ After that, there should be a pause for the same period of time as for the lighting of an LED. ... what happens after the pause? \$\endgroup\$
    – jsotola
    Nov 8, 2021 at 19:25
  • \$\begingroup\$ @jsotola It starts from the beginning again. \$\endgroup\$
    – Daniel
    Nov 8, 2021 at 19:33
  • 1
    \$\begingroup\$ that information belongs in the question, not in a comment ... please edit your post \$\endgroup\$
    – jsotola
    Nov 8, 2021 at 19:34
  • \$\begingroup\$ @nanofarad a composition of flipflops Yeah that's the thing. I tried to build a 4-bit asynchronous counter with flip-flops this afternoon, but it went wrong and I realized that I needed a "digital source". \$\endgroup\$
    – Daniel
    Nov 8, 2021 at 22:21

2 Answers 2

2
\$\begingroup\$

Here's a possible solution to to this problem. What you can do is make a simple FSM (finite state machine) with a counter and some logic gates. Below is one I did to get a LED 'pixel' to cycle between red, green, blue, and white.

enter image description here

You could do something similar with a 3 bit counter (you need at least 7 states). Could use a decoder to turn on one LED per state.

\$\endgroup\$
0
\$\begingroup\$

I think the easiest way would be to use a 4017 with the LEDs connected to outputs 0-4 and output 6 fed back into MR.

\$\endgroup\$
1
  • \$\begingroup\$ Absolutely!!!!! \$\endgroup\$
    – user173271
    Nov 16, 2021 at 10:54

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.