Questions tagged [transistor]
A semiconductor component used for amplifying or switching electrical signals. Use this tag for discussing transistor circuits.
106 questions
2 votes
1 answer
219 views
ESP32 LED PWM fade not working?
Not sure if this belongs more in an electronics SE, but I'll give this a try. I'm trying to use an ESP32-C3 and an NPN transistor (2N5551) to PWM drive an LED (values below). I'm trying a simple fade, ...
- 149
1 vote
2 answers
271 views
PWM with a TRANSISTOR on flexible LED filament
I would like to create a custom lighting, with PWM capability, powered from battery. I would like to use flexible led filaments, and since those consumes more than 40mA, I can't use them directly on a ...
- 65
-1 votes
1 answer
384 views
Problems in running two solenoid together at the same time
I am trying to activate two solenoids (12V/350mA, connected to a 12V/1A adaptor) at the same time using the TIP120 NPN-transistor and 1kohm resistor using the UNO board. Using a simple program, void ...
4 votes
2 answers
1k views
Controlling a 5V fan and ultrasonic fogger with an arduino - do I need an external power supply?
I know the whole controlling a fan with an arduino thing is getting old, but somehow I still don't get it to work. Tried to answer it based on other questions but I am too much of a newbie to ...
- 43
0 votes
1 answer
934 views
arduino 28BYJ-48 stepper only whining, not rotating
Edit, this question has been answered in the comments by chrisl, and also after retesting the code with delay() which showed I forgot to update my lastupdate variable(eerst), I have answered it in the ...
- 254
0 votes
2 answers
539 views
Switching fan on with transistor, fan running very slowly
I want to control a fan with an arduino from 0 rpm to full rpm. Using a (modified) pwm signal from the arduino I can control the speed w/ the pwm signal, but it cannot go all the way to 0 rpm. So I ...
- 13
1 vote
0 answers
308 views
PID cooler temperature control
Hello Hello I am making a controller of a small cooler (dry ice) PID but Im not sure if I am using the indicated mosfet Im trying with a NPN 222a and my second option is IRFZ44 Which would be the best ...
2 votes
3 answers
897 views
Why are transistors necessary before LEDs?
Below is the small RGB LED circuit I'm trying to build. My question is why are the 3 transistors necessary, and can I not link the LEDs directly?
- 39
3 votes
2 answers
176 views
connecting a small motor to arduino using a transistor
I want to connect a small motor (water pump) to an arduino, and I am not sure about the circuit. The pump is small, works with 3.3V, but consumes 0.1A so I decided to use a transistor. The one I have ...
- 31
0 votes
1 answer
701 views
Motor not switching with 2N3904
I have a small motor, it powers fine from the 3V3 and GND output of the arduino nano ble 33. However I need to be able to switch it on and off. My first attempt was to use an output pin, but that ...
- 141
0 votes
1 answer
175 views
Switching 4.2V circuit with 3.3V Arduino GPIO
I am trying to learn about MOSFETs and see this p channel MOSFET and this tutorial. I am trying to use a 3.3V arduino GPIO pin to control a load that is powered from a 4.2V battery in much the same ...
- 170
0 votes
1 answer
75 views
Is it possible to use the same power source for the arduino and a high current
I've need to control some leds which draw 300mA with an arduino (actually an atmega) and after some searching I think the following is the circuit I need, but I'm not really sure if the power source ...
- 9
1 vote
1 answer
449 views
Arduino H-bridge for rc car
I've got an old rc car laying around, of which i would like to swap the insides, but re-use some of the parts that are already in there. The car runs 2 dc motors: one for steering, one for throttle. ...
1 vote
0 answers
211 views
Motor not working when using Nano 33 BLE and transistor because of low voltage
I'm a beginner using a new Arduino Nano 33 BLE to power a low voltage motor. I've tested that the motor can run using a standard 1.5V AA battery when connected directly, but I cannot get it to work ...
- 11
0 votes
1 answer
331 views
How can a DC motor (toy) be run with only an Arduino and transistor without an external power source?
I'm trying to understand this circuit found here. I understand that the Arduino cannot directly run a DC motor because it can only supply 40mA of current and also due to the back EMF which can damage ...
