PWM Signal to 10v

Hello,

I have a pretty basic problem and I also think I have a solution, but I just want to run it by some people that might know a bit more about this then me.

I need to up my PWM signal from 5v to 10v. I will be using the signal to drive a PWM controlled Meanwell driver.

It states that it needs a low = 0v high = 10v PWM signal.

My plan is to use a uA741 Op-Amp to boost the signal to 10v.

I don't need any heavy load on the circuit as it is only a signal to the driver and will not be powering anything. Is this going to accomplish what I need done?

Thanks for your help,

Jason

a 10v supply, a transistor and some resistors is all you need :slight_smile:

I plan to use a 12v supply with a LM317 to drop the voltage to around 10.3v. The supply would then feed to the uA741 Op-Amp to achieve the 10v signal to pass on to the drivers.

http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/opampvar.html#c3

I just need to know if this is going to accomplish what I need.

Cheers,

Jason

i think a simple transistor (2n2222) would suffice for this. The 0 - 5v PWM signal from the arduino controls the base of the 2n2222 that in turn controls the 10v going to the Meanwell driver.

I don't see the need for an opamp.

To elaborate on what daveg360 said, feed your 5v signal through a resistor to the base of a transistor. Emitter to GND, collector to 10v through another resistor. Then tap your 0-10v PWM signal from the collector.

This will invert the duty cycle of the PWM so handle that in software.


Rob

So, if I am reading it right, use the transistor to open and close the ground on the 10v circuit that is connected to the drivers?

Umm, I think so. I prefer to look at it this way.

The collector resistor pulls the meanwell input high, and every now and then the transistor overrides that and pulls it low.


Rob

I know it's a bit of an ask but would someone be able to knock-up a little drawing for me? It might make a bit more since to me if I have something to look at.

No problems,

Resistor values may vary but that's the idea.

(oops, VCC should be 10v)


Rob

Thanks mate looks good,

You mentioned that I would need to invert the PWM signal in the software. I imagine that will be a little more complex than just reversing the values. I'll have a bit of a dig around and see if I can find anything on the website about it.

Thanks again,

Jason

I imagine that will be a little more complex than just reversing the values.

I don't think so, if you invert the value that would do the trick.

analogWrite (pin, value); // B00000011 or 3

becomes

analogWrite (pin, ~value); // B11111100 or 252


Rob

I'll give that a try once I get all the pieces together.

Do you know of an IC that would contain multiple 2n2222 or similar transistors? I need to have 6 different channels and would like to try and combine them into the smallest package that I can. I don't have a problem putting together 6 individual 2n2222's but would be much easier as one larger package.

What is the best way to determine the resistor values? Is there a formula or a calculator that i can use, or is it just trial and error?

Thanks again,

Jason

Do you know of an IC that would contain multiple 2n2222 or similar transistors?

Have a look at ULN2801/2/3/4/5, ULN2001/2/3/4.

Even better these chips don't need base resistors so you will lose 6 components.


Rob

Hi
There are drawbacks uA741 slow.

This is my favorite circuit.
Supply Voltage 2 / 3 to determine the voltage.
Voltage of the power / trigger 2 3 / 3 return, and window discrimination.
(Hysteresis circuit)
The output can be expected to drive a powerful totem pole.