Go Down

Topic: Create PWM with amplitude of +9v and -9v (Read 1 time) previous topic - next topic

vova1610

Hi, I have an Arduino Duemilonove and Ardumoto shield. Is somewone know if it is possible to create a +/-9v PWM with frequency of about 50Hz using those resources? I also need to control the Duty Cycle..

Grumpy_Mike

Yes it is easy you need a split voltage supply of +/- 9 volts and a pair of transistors. What sort of current do you need to drive with this?

However I suspect that you don't actually want to do this so we need to know what you actually want to do and if this is the right way. So many beginners waste a lot of time asking for things that they don't really need, but theynonly think they need.

vova1610

I need to drive actuator, which is about 500-600mA. It is for My final project in university.

Grumpy_Mike

That is a lot of current. Anyway a class B push pull amplifier stage should do it.

vova1610

I know that Ardumoto shield can provide a negative DC (-9v) voltage while setting: digitalWrite (dir_a, LOW), and positive DC (+9v) while setting: digitalWrite (dir_a, High). Therefore i can get a PWM of +-9v without any additional transistors, but i don't know if i can do it in high frequency.. How can i make delay of HIGH and LOW to be less than 1ms.

Go Up