Comparing sine and triangle waves

hello everyone,
i'm a student from belgium and i have to program an BLDC motor with labview. for this i need a PWM (pulse width modulated) signal. i want to do this by comparing a sine wave with a triangle wave, theoretically this should give me
block wave with different duty cycle. i have added a picture to make my question more clear.
as you can see there are two triangle waves to compare with the sine wave, every time one of the triangle crosses the sine wave a pulse is generated and stays high untill the next cross.
thanx in advance

Hello,
When i tried to reproduce this problem, I couldn't succeed in it.
While looking at you jpeg I noticed that you have connected something to the channel input of your ddt to waveform convertors. You should remove this (except if this was your intention) and then everything should work.
If this doesnt work, then you can always use the file attached to this post.
Kind Regards,
Thierry C - Applications Engineering Specialist Northern European Region - National Instruments
CLD, CTA
If someone helped you, let them know. Mark as solved and/or give a kudo.
Attachments:
testje.vi ‏420 KB

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Comparing sine and triangle waves

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