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PWM signal creation with NI USB-6002

Good evening,

 

I am relatively new to LabVIEW, and I'm working on a university project that involves generating a PWM (Pulse Width Modulation) signal using an NI 6002 device to control a blower.

 

The challenge I'm facing is that the datasheet for the blower specifies a required signal frequency of 25 kHz, although I've observed that it works at 10 kHz when using a bench power supply.

 

I've attempted to generate the signal using software timing to control a digital output, but I've encountered limitations. I initially used the timed loop function, but it appears to have a maximum frequency of 1 kHz (can someone confirm this?). This makes it unsuitable for my needs.

 

In my efforts to overcome this limitation, I've started exploring analog outputs. Specifically, I used the LabVIEW library example titled "Voltage - Continuous Output.vi." While this approach has shown improvement, it's still restricted by a maximum sampling rate of 5 kS/s, resulting in an achievable signal frequency of only 2,5 kHz.

 

Given my limited experience with LabVIEW, I'd greatly appreciate any recommendations or guidance on how to address this issue. It's important to note that I'm not in a position to change the hardware device. Additionally, I'm puzzled by the fact that the datasheet indicates an 80 MHz sampling frequency, and I'm curious about how this relates to my current limitations.

Thank you for any assistance or insights you can provide.

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USB-6002 is a "low-cost" device and hence could not generate a 25kHz PWM.

 

BTW, 80MHz is the timebase used as a reference for the sampling clock.

santo_13_0-1697203018773.png

 

 

 

Santhosh
Soliton Technologies

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