Hi Folks,
I have a simple question that may have been already answered. I have a H-Bridge MOSFET Driver circuit that takes a microcontroller PWM signal and amplifies it to a 12V PWM signal used to drive a 4A 12V DC Brushed Motor.
We have it working on a PIC16F microcontroller and it works great keeping a constant "8V" looking signal (PWM wave), but it can also dial down to lower "voltages" and higher ones as well. The problem is that I do not have the PIC code for it.
When I remove the PIC16F and replace it with an Arduino and use Pin 3 or 5 to output a PWM signal, it also works just like above, however the difference is when using the Arduino, I hear a high-pitch whine. When doing the exact same thing with the exact same circuit and motor, but on the PIC16F, I don't hear the whine.
What am I doing wrong, and how to I make the Arduino not make the whine? Just using this basic code:
void setup() {
pinMode(3, OUTPUT);
}
void loop() {
analogWrite(3, 166);
}
The MOSFET Driver circuit is based on the Linear Technologies LT1158:
http://cds.linear.com/docs/en/datasheet/1158fb.pdf