What's a good waveform generator IC to build a circuit (project) around? - Page 1
Forum section: electronics / projects

author: SharpEars
author_rank: Unknown
timestamp: October 22, 2014, 05:21:11 pm
content: Just for kicks, but high bandwidth and the ability to do lots of different waveforms would be cool.

author: microbug
author_rank: Frequent Contributor
timestamp: October 22, 2014, 05:38:15 pm
content: I'd be looking at DDS chips, for a start. Analog Devices do several varieties.NB: You can buy wavegen boards built around Analog Devices chips from China, they would probably do.

author: Neganur
author_rank: Unknown
timestamp: October 23, 2014, 06:06:49 am
content: "lots of different wave forms" and "high bandwidth" will definately take you into I/Q (quadrature) modulation, but I guess the most basic forms (triangle, square, sine) could be done with a regular DDS chip? My favorite is the AD 9914 (expensive little bugger though)Have a look at the parametric table in the lower half of this website:http://www.analog.com/en/rfif-components/direct-digital-synthesis-dds/products/index.html#Direct_Digital_Synthesisthere are also DDS chips with 4 channels (the AD9959 with 500 MHz clock) which maybe could be used for two channels of I/Q modulation. Maybe a nice 2-Ch Arb function generator project?

author: awallin
author_rank: Frequent Contributor
timestamp: October 23, 2014, 01:17:37 pm
content: FPGA with lots of fast memory close by + 12/14-bit fast DAC ?not sure what sample-speeds the economical (100eur) fpga dev-kits could achieve to a 12/14-bit dac? any ideas?

author: gnif
author_rank: Unknown
timestamp: October 23, 2014, 01:26:05 pm
content: Not as fast as a FPGA, etc... but cheap and effective.http://hackaday.com/2014/10/22/function-generator-with-zero-cpu-cycles/

author: miguelvp
author_rank: Super Contributor
timestamp: October 24, 2014, 06:00:02 am
content: I just got this today:http://parts.arrow.com/item/detail/arrow-development-tools/bemicromax10With a DAC, 12-bit, SPI interface (Analog Devices AD5681) among other things. $30 but they are out of stock already.Then again, I don't know if you consider 50MHz high speed.They also have an interposer connector that will connect to some Analog Devices dev boards

author: tggzzz
author_rank: Super Contributor
timestamp: October 24, 2014, 01:38:16 pm
content: Quote from: SharpEars on October 22, 2014, 05:21:11 pmLet's stamp out meaningless adjectives such as "high" and "lots". Quantify the bandwidth: 1kHz or 100GHz? What waveforms: arbitrary/length?

author: SharpEars
author_rank: Unknown
timestamp: October 24, 2014, 11:15:22 pm
content: Quote from: tggzzz on October 24, 2014, 01:38:16 pmVariable frequency 1-100 MHz square wave/arbitrary length.

author: Marco
author_rank: Super Contributor
timestamp: October 25, 2014, 12:43:12 am
content: I don't know of any hobbyist 100 MHz+ AWG's, couple of random links for 100MHz+ sine generators based on DDS's I ran into recently :http://www.pukshofer.com/Privat/Projekte/VNWA/Hauptseite.htmhttp://www.ebay.com/itm/NWT500-Sweep-analyzer-amplitude-frequency-characteristic-analyzer-/261542501615?pt=LH_DefaultDomain_0&hash=item3ce525dcefhttp://www.gempillar.com/dds-ad9910.htmlhttps://labtronics.wordpress.com/tag/dds/http://www.mikrocontroller.net/topic/166831VNWA is readily available as well as schematics, the NWT-500 which is available is only an imitation of the original which uses the same PC software ... the hardware itself is different and closed source.

author: Macbeth
author_rank: Super Contributor
timestamp: October 25, 2014, 01:28:40 am
content: Or you could be trying to do old school sine, square, and triangle?XR2206 ICLooks like a similar very cheap IC to the one I used to make my first function gen back in the late 1980's. It was better than any of the test equipment we had in college at the time that's for sure!

author: bigsky
author_rank: Regular Contributor
timestamp: October 25, 2014, 08:06:31 pm
content: On the subject of old-school, I'm surprised no-one's mentioned the ICL8038

author: dannyf
author_rank: Super Contributor
timestamp: October 25, 2014, 09:55:23 pm
content: QuoteLT has quite a few chips (voltage controlled oscillators).Otherwise, a typical LC oscillator (1648 for example), or even a discrete solution can easily get you there.

author: robimarko
author_rank: Regular Contributor
timestamp: October 25, 2014, 09:56:39 pm
content: I am amazed that nobody mention MAX038

author: Skimask
author_rank: Super Contributor
timestamp: October 25, 2014, 10:43:28 pm
content: Quote from: robimarko on October 25, 2014, 09:56:39 pmTry to get one lately?Like in the last ~10 years?

author: Neganur
author_rank: Unknown
timestamp: October 26, 2014, 01:21:54 am
content: I'm sure those adjectives are relative but would you really call the good old 8038 "high bandwidth" ?gosh, now I have to see what date code the one I have has.

author: robimarko
author_rank: Regular Contributor
timestamp: October 26, 2014, 05:31:05 pm
content: Quote from: Skimask on October 25, 2014, 10:43:28 pmWhat about hundreds on ebay

author: SeanB
author_rank: Super Contributor
timestamp: October 26, 2014, 05:47:38 pm
content: high bandwidth for the 8038 if you consider 1MHz as high frequency. Good for audio if you did not mind the distortion though, or the fact it ran hot enough to cook with.

author: alex.forencich
author_rank: Frequent Contributor
timestamp: October 26, 2014, 06:17:19 pm
content: The hantek htg2002b is capable of generating waveforms up to 100 MHz with a 250 Msps DAC. An effort just started up last night to write an open source version of the firmware that will improve the performance of the unit. I will be working on the FPGA code for the actual waveform generation portion.

author: atferrari
author_rank: Frequent Contributor
timestamp: October 26, 2014, 07:17:49 pm
content: If you can:Program a micro to handle itDesign output circuitry (filter) for itDesign a reasonable PCB to accomodate all thatyou could use the AD9834 (sweeping generator).I strongly suspect that my Siglent function generator was built around it.Datasheet is not hard to understand at all.

author: Skimask
author_rank: Super Contributor
timestamp: October 27, 2014, 12:23:01 pm
content: Quote from: robimarko on October 26, 2014, 05:31:05 pmWhat about the fact the MAX038 was discontinued back in '06?Still think you can get the genuine thing?