Need to get higher voltage or higher amps.

Hi! This has nothing to do with Arduino so sorry about that, I just don't know other places where smart people can give me answers about electronics. Anyways, I have been making a little password lock system using npn transistors (BC547B and two 2n551's) that will allow you to open and close a door using a motor if everything is correct. I will post the circuit below. Basically it is a not gate combined with an and gate. When everything is correct, it can light up an led but definitely not drive a motor. What can I do to be able to drive the motor? Can I change resistor values? Get a boost converter? I'm not sure. Thanks! It is part of a clock I am making so that my teacher can store stuff.

Rapid :)

Sorry for the bad picture quality…

You could replace the LED with an NPN power transistor. Connect the transistor Base to the right side of the 330 Ohm resistor, the Emiiter to GND and the Collector to the motor. The other pole of the motor You connect to motor power plus.

Hi again! I believe it is a current problem, and I will try this. But so to be clear, base to resistor, Emitter to GND, and Collector to negative of the motor, and the positive of the motor to vcc? I'll try. Thanks!

Do not forget the flyback diode across the motor to protect the transistor from the inductive kickback when the motor power is shut off.

IT WORKED!!! THANK YOU SO MUCH!!!!!!!!! And wait what diode?

Place a diode across the motor. Cathode to motor + and anode to GND. That will kill the power generated by the spinning motor at stopping. Else the transistor will get damaged.

Question: I made myself a three way switch so the door can go up and down by switching the polarity that I control. So would I need 2 diodes to keep it from going both directions because the polarities switch, or is this a dumb question?

I would need to see how everything is connected. You cannot have forward and reverse with a single transistor motor driver. That requires an H bridge if done with transistors. H bridge motor drivers have the diodes built in. If the motor is connected to a mechanical switch no diodes are required.

If you are using a pair of DPDT relays They act like a H-bridge. The diode goes from ground (before the MOSFET) to power

this way the relays and motor act like one unit for the MOSFET.

Post a sketch of your circuit to help make sure things are clear.

I’m working on creating the circuit right now. I will include the new power transistor part of it in. I will upload it as soon as it is done. The way I did the three way switch this is by using 4 buttons and making a little rocking switch that has a kind of see-saw design that press two buttons on each end. I will post a pic of that right now.

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Ok I finished the circuit but didn’t add the motor circuit. The circuit is the same as in this video, but implemented differently: DC Motor Reverse Forward Switch - Two Direction Control - YouTube
Basicly I push two push buttons at a time using a see-saw type switch. here is the rest of the circuit. R7 and R1 are where my switched for the password will be connected and then the other end of the switch to 5v.

So does anyone know what to do...