Picture of Low cost  waveform generator (0 - 20MHz)
This Project comes from the necessity of getting a wave generator with a bandwidth over 10 Mhz and an harmonic distortion under 1%, all of this with a low cost price.
This document describes a design of a wave generator with a bandwidth over 10MHz , which produce:  sine, triangle, sawtooth, or square (pulse) waveforms with an harmonic distortion under 1%, duty-cycle adjustment, frequency modulation, TTL output and offset voltage. It is also presented the design of a frequency counter.

Step 1: Parts list

Picture of Parts list
This is the main parts list.
The main part, MAX 038 is a discontinued part, but it still can be bought .

It is attached  an approximate budget.

bmutlugil17 days ago


Where can the MAX038 chip be bought, I can not buy a working one..

swander1 year ago
Very cool. Is there a way to output this to a PC so as to use its display? CRT's are getting a little scarce in small sizes. Maybe mic jack? That obsolete IC can still be had for about $21 US.
Carlosrhrh (author)  swander1 year ago
If you need Know the frequency, I will try to upload a frequency counter as soon as possible.
nuninu Carlosrhrh4 months ago

I like your design and I'm building this project.
Could you upload a schematic of a frequency counter?

jmrt11 months ago

i checked the voltage on the vref it is still in the negative range. can you help me what is the problem?

Carlosrhrh (author)  jmrt11 months ago
i think that you must check first that the chip work correctly, because i bought 11 chips, and only worked one. (10 from china and the good one in england).
You can test with an easy circuit, like it is showing in the chip pdf.
you dont have to use this pin, you can use a voltage divisor instead. (see the circuit explanations for farther infor
Carlosrhrh (author) 11 months ago

hello jmrt.

The pin1 (REF) of the chip MAX038 it is a positive voltage, and it is an output.

All the designe of this project is based on the MAX038 PDF.


jmrt11 months ago

hello. we did this project and our supply V- = -5v and
V+ = +5v. but why does the input voltage in pin1 is in negative??:( Vref= -3.5v)

pls help us. this is for our project study.. thank you!! :)

robotmaker1 year ago
can asy make one much cheaper with a waveform generator ICL8038
IT GIVE SAWTOOTH,square,sine and other circuits can be added to easy,op amp circuits and more
Carlosrhrh (author)  robotmaker1 year ago
I know, but the MAX038 have a bandwidth of 20MHz or more, and the ICL8038 have only a bandwidth of 300KHz, so this is a low cost "high" waveform generator... :)

FabLabLeon1 year ago
Amazing job!!!!
I just ordered the parts, this is an awesome design around an awesome chip !
I was looking around for a cheap and decent function generator for some time now and I don't have the time now to to deepen myself in making/designing a desent circuit for a diy function generator, but you did al the work for us !
You really helped me, thank you, its highly appreciated !
If you have some problem when you build it, only let me know and I will help you.
guds7771 year ago
is it useful as a 220v 0-60 hz motor controller..
Carlosrhrh (author)  guds7771 year ago
It is not.
Edgar1 year ago
Voted, and Blogged about it:
Edgar1 year ago
Nice! Like the Fabbing side of it, too. :)
Voted, and also Blogged about it, too useful to pass un-noticed:
I really like the box.

Good show.

pfred21 year ago
That is one expensive integrated circuit. I would hate to let the magic smoke out of that one!
Carlosrhrh (author)  pfred21 year ago
It is more expensive to buy a new one with this characteristics.
It cost to build about 100 euros.
Good to know. The whole project is very interesting and an impressive end result. My only complaint about the article is that if you're going to hype something as 'low cost' right in the title, then saying how much it cost should be right in the project description. I went though every page of it trying to figure out exactly how 'low cost' is low cost'.. heh
Carlosrhrh (author)  hexidismal1 year ago
Hello. I already put a budget attached in the second step.

Unfortunately, 'low cost' is a relative term. In this kind of thing, it's low compared to what a commercial product with similar specs would cost.. Look around the surplus market for that chip, you may get lucky and find one for a lot less.
Yeah the Max038 is obsolete now anyway like the XR2206, best not to make new designs using it.
That's not entirely true, it depends on which sort of performance you want. You could build a high-end 12 bit DDS version that would work quite well up to 10 MHz pretty cheaply using a low-end FPGA, DAC and a good output filter! Total cost would probably be somewhere around 30-40 Euro.

On the other hand, if you wish to go analog:
If you need a low distortion sine-wave oscillator nothing quite beats a Wien-bridge oscillator with a light-bulb is a good choice. For higher frequencies a Collpits-oscillator isn't a bad choice, but keeping it running over a wide frequency range of several octaves is problematic. But I should probably stop before I scare people away. :)
ajoyraman1 year ago
This is good work ! I am a fan of another obsolete part the Intersil 8038 which works well up-to 50 kHz. Unfortunately these analog IC's have disappeared.
aldente461 year ago
Thanks Carlosrhrh
I've had a MAX038 in my parts bin for many years waiting for me to get around to making it a project. Now that I've seen your efforts and your PCB artwork I have been inspired to finally go ahead with it. Aldente46
I love it
Awesome job! Looks very professional!
Carlosrhrh (author)  Infinitevortex1 year ago