I am trying to modify the circuit that resembles a 3-way LED lamp. For example, first press on switch turns on one LED, second press turns on two LEDs, third is all LEDs, and fourth will turn off all LEDs.

I tried taking out the capacitors in between each ring counters but it does not work nor does directly connecting R2, R4, R6 and R8 to the PB switch. I looked at solutions online but mostly showed a circuit where all LEDs turn on together or by using a 555 timer. I am trying to not use any ICs as much as possible. enter image description here

  • 3
    \$\begingroup\$ When people don't want to do things the normal way, it improves the question (and answers) if they say why. \$\endgroup\$ May 23, 2014 at 13:47
  • \$\begingroup\$ Sorry because I am trying out a project i saw online \$\endgroup\$
    – txrxmo
    May 23, 2014 at 13:52
  • \$\begingroup\$ You need a proper counter/shift register and then using the combinations of outputs from that in a truth table and using AND or NAND gates to implement the logic that you need \$\endgroup\$
    – KyranF
    May 23, 2014 at 15:11

2 Answers 2


From what I can tell from your question, you are trying to do logic operations with buttons as inputs and LEDs as outputs.

You may want to get familiar with things like truth tables, De Morgan's laws, circuit/logic minimization, and so on. There's simply an entire academy built around logic and I have a feeling you're trying to sneak past it.

For now, forget about driving the LEDs, think of them as being either on, or off. Think of your buttons as being on or off as well. These two states are described as 1/0, TRUE/FALSE, or as we like to call them - HIGH/LOW. It seems to me that this is the thing you're asking.

This is an enormous topic and is entirely impossible to cover in a single answer. But worry not, there are megatons of study material out there.

Edit: As I obviously misunderstood your question, the information I provided doesn't relate to your question very much.

  • \$\begingroup\$ i would need more than one button for the operation? \$\endgroup\$
    – txrxmo
    May 23, 2014 at 15:10
  • \$\begingroup\$ No you wouldn't, I simply misunderstood your question. \$\endgroup\$
    – Dzarda
    May 23, 2014 at 15:17
  • \$\begingroup\$ Is there any way to modify the circuit?? \$\endgroup\$
    – txrxmo
    May 23, 2014 at 15:22

You can either try and find some extremely novel Analog way of accomplishing what you're trying to do, or you can fork over the however-many-cents it costs to get a Digital Logic Chip, hook up a few wires, and you're ready to go. I think the real issue comes down to this: How much do you want to bang your head against the wall? There's no sense in trying to kill a mosquito with a cannon. I think that mirrors what other people are saying as well.

  • \$\begingroup\$ i would have done that in the first place but i am trying to stick to pure analog. Its not about the "real issue". \$\endgroup\$
    – txrxmo
    May 24, 2014 at 4:29
  • \$\begingroup\$ Ok. That's fine. Have you attempted to simulate this in a simulations program like LT Spice? LT Spice is free, and might help you to better understand how this circuit works and what you can do to fix it. Have you done any simulations? \$\endgroup\$
    – zklim
    May 25, 2014 at 14:25

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