Help to design an electrical circuit properly

Hello to all,

I write this letter with my head held kind of low. it’s that way because I feel that I failed in my task of building my kids a couple of cool toys for the summer. Designing, 3D printing weren’t the issue. The problem has been creating the circuit that powers these things the way I want to is where the trouble is.

You see, I’m barely an electrician. As in half the time when I’m looking at a wiring schematic I have to go online to see what the symbols represent. I have all the tools to build whatever I want, just not quite the skill to design an electrical circuit properly.

I’ve been watching a lot of videos of 555 timers on Youtube. For some reason I just cannot get mine to work properly. I’ve even tried a couple of transistors with resistors, capacitors and was unable to do that as well. I see many other videos of it working. I do the exact same thing but it’s not working for me for some reason.

What I’m hoping is somebody can help me out with the design for what I need. I think part of the problem is that all those flip flopping circuits are usually just powering leds.

My toys are going to need more than that. they’re going to have a couple of little Motors in them. Size is an issue. I want to keep everything small. I want to use some coin batteries that are paralleled together and then in series, or is it the other way around?

I’m going to put what my needs are and the components current/voltage draw is. I hope you can help me with a schematic drawing.

I will be using Coin Batteries, rechargeable Lithium 3V 11MAH. I can use several in series or parallel. What the circuit needs I will supply,

I want to use a mini tactile switch for on off MAXIMUM VOLTAGE: 16 VDC MAXIMUM CURRENT DC: 50 mA DIELECTRIC STRENGTH: 250 VA C (1mn) CONTACT RESISTANCE: ≤ 500 mΩ INSULATION RESISTANCE: ≥ 100 MΩ BOUNCE TIME: ≤ 10 ms.

I want 1 circuit output to power an electrical motor rated at Voltage 3.7V,Current: about 150 ma. Run time from 2 seconds to 4 seconds.

The second output circuit will need to power 1 LED, 20ma 3 - 3.2 v… I will also power an additional motor whole the led is running, Motor will need 2.7 - 3volts less that 100 mA

I would very much like after turning on the first output will run. Then shutoff when the second out turns on. After it turns off the system will pause for the same length as either output lines run for then start again.

Finally, I would like the system to have a delayed runt time or off delay. Total run time for 5 to 10 minutes.

Any help would be awesome!

Please contact me at 725-267-4095,



Hi Doug,
Do you have an existing schematic you’re working with ? What are the problems you’re having with the 555 timers ?

please send your email and I will forward what I need help with. Also include a price for your time.

From your description, Arduino sounds like the best option to me. But if you are not familiar with coding, 555 seems to be the only feasible option.

You can see the LED dimmer and and motor speed controller circuit here:

Here you will get the basic idea.

However, if you have already made a circuit design or PCB, you can post those to:

I could really use help designing 3 small 3v DC circuits. Please leave your contact details or send me a message at, 725-267-4095


Thank you for contacting Digi-Key , we do not design circuits but we do have companies that we work with that may be able to help you with this , below is a link for them .

Thanks Craig

Can you show me how to do a double circuit? By that I mean one side is a flip side flip flop and the other side is like a strobe.

What I’m hoping for is this, 2 LEDs with a buzzer speaker with its own transducer on one side of the flip-flop staying powered for less than 1 second. The other side of the flip flop the power DC motor will stay lit for about 3 seconds. Both of these are using Less Than 3 volts. Matter of fact the motor I’m using only uses 1.5 volts at 20 milliamp or something like that.

Then I would like a strobe circuit to power the whole thing. The flip flop powered for say 20 to 30 seconds then shut off for 20 or 30 seconds then repeated continuously.

If you can show me how to make this circuit, that would be awesome.

Myself and kids would be forever grateful.