12 MHz Waveform Generator- What Does That Even Mean?


The Analog Discovery 2 has many tools, and one of the most commonly used is the Waveform Generator. You can send a large variety of signals, from your basic sine wave, to modulated signals. It’s also used in the Network Analyzer to provide the frequency inputs.

We say in the spec sheet that the Waveform Generator can provide 12MHz with the BNC adapter, but what does that really mean? Well, that means that when sending a signal of 12MHz with the BNC Adapter the signal will hit the 3dB point, meaning the amplitude will fall to .707. Without the BNC Adapter, this will occur at 9MHz.

Let me show you:

Here is a signal that is well within the spec, a 1MHz sine wave. Here you can see that the amplitude is at a full 1V.

Here you can see the 1MHz signal with full signal integrity.

At 10MHz without the BNC Adapter, we are just above the promised spec of 9MHz, and you can see that the amplitude has fallen below the .707 mark. A usable signal for many projects, but not ideal.

The 10MHz signal with (C1) and without (R1) oversampling. Since it is just outside the spec, it is just under the 3dB point.

Now lets go way out of the range of the specifications, a 25MHz signal.

Here you can see the 25MHz signal. It is way out of the spec so the signal integrity has been significantly diminished.

Here you can see that the amplitude of the signal is between .2 and .4 and the quality of the signal is diminished significantly. Frequencies outside of the spec can be access in no limits mode, but are mainly used for testing by our engineers.

If you want to try out the software that runs the Analog Discovery 2 you can download it and test it in demo mode for free.

Comment below if you have any other specifications you’d like clarified. And make sure to let us know what your working on with the Analog Discovery 2!

Share on FacebookTweet about this on TwitterShare on Google+Pin on PinterestShare on RedditShare on TumblrShare on LinkedInShare on StumbleUponEmail this to someone

About Author

When I started school I wasn’t interested in any of things I’m passionate about now. In fact originally I started out wanting to study art. But then I decided I didn’t want to have people telling me what to create, so I changed to music. Then I decided I didn’t want to ruin a hobby by making it my career. At the same time my Physics class was teaching a unit on the physics of music, and I thought that was way interesting, so I changed to physics. Then by the time physics was over I decided that the coolest part of physics was electricity and magnetism, and I may as well get a degree that transfers directly into a career. So while all this was happening, I was attending Shoreline Community College, and during that time I found my passion, or rather presented itself repeatedly, until I realized, maybe I should take a hint from the universe. While at community college, I was asked to help at the high school by tutoring chemistry students. Then I was asked to help at the elementary school by being a math Olympiad coach. I continued both because I found I really enjoyed it. I also had an opportunity, and was hired to be a tutor in the Math Learning Center at the Community College, a job I really loved. At the same time I was working as a Nanny, which I had been doing for several years, the main reason because I could and would answer the hard questions the kids asked honestly (i.e. why is the sky blue). I then was recommended by the patrons of the MLC to the transfer tutoring center (private tutoring,) and developed a wait list of students. Through all these opportunities at some point I realized that I loved watching people go from totally lost, to masters of a subject. I was also forced to admit that having all these opportunities continually renewed, I must have been somewhat good at it. So I decided I wanted to teach, which fits with my mission oriented personality. I saw a serious lack of passionate ECE professors in the institutions I attended. At WSU I continued this trend by being ask to TA for computer science and electrical engineering, being a TA for a total of 4 semesters. This continued by getting an amazing opportunity in my first semester at Washington State University to work at Digilent, an educational company. So even if I didn’t want to teach, turns out I can’t avoid it. Luckily it is my main passion.

Leave A Reply