Tagged Questions

3
votes
2answers
121 views

arduino pulse to transistor power maximum

Hello I want to get a confirmation that what I am doing is not going to fry my Arduino Mega. The sketch I am using to send a pulse out on pin 8 to a 2n3055 that is switching 12 volts is this: ...
2
votes
1answer
97 views

Simplest design approach for PWM control with power MOSFET

I'm designing an application in which the current running into a load is controlled by PWM. A microcontroller generates a PWM cycle at 20kHz and this signal is used to control a MOSFET which is ...
1
vote
2answers
657 views

Transistor / mosfet for PWM dimming of 30W RGB LED

I am building a led mood light with a high power RGB LED (30W) using 3 constant power supplies for each color. These are the items I had in mind (but open to suggestions): 30W Integrated RGB LED ...
2
votes
2answers
646 views

Driving a Fan using TIP120 to PWM from Arduino

So I have recently started my first group project, which is to design an autonomous hovercraft. We decided to drive the propulsion fans (which are rated at ~7 V and our battery runs at 12 V) using a ...
3
votes
2answers
987 views

Driving PWM lights with parallel darlington arrays

I am building some service light arrays, which I want to operate using the Arduino's PWM outputs. This lighting is going to be powered by 5V OR 12V with a nominal current of 700mA per array. There ...
3
votes
3answers
865 views

Piezo circuit issues

In my circuit I am seeing strange behavior from my piezo. I am driving a 4Khz (TDK PS1240P02BT) piezo buzzer with a BSS138K N-channel logic-level enhancement FET. The PWM output of my microcontroller ...
4
votes
4answers
2k views

Transistors and PWM

I'm little confused about this one and don't know where to start. The idea is to have micro-controller or FPGA output PWM signal (5V or 3.3V while PWM is 100%), and then use a transistor to power ...
3
votes
2answers
223 views

Too slow falling edge

I constructed this circuit in the simulator Multisim11. It should switch current 15A trough resistor R1 for PWM regulation. I need to make it work for frequency 2kHz. The function generator XFG1 on ...
2
votes
1answer
403 views

Voltage controlled voltage source

I am designing a high powered LED driver controlled by a microcontroller. Now it would be very easy to make a constant current limiter so I don't burn out my LED. I have a bunch of LM317's and ...