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Electronics => Beginners => Topic started by: Legion on February 08, 2014, 09:28:50 pm

Title: Analog vs Digital Function Generators and Frequency
Post by: Legion on February 08, 2014, 09:28:50 pm

I've seen it stated in many places that it's useful to have both an analog and a digital oscilloscope. Does the same hold true for function generators? Are analog generators better at non-sinusoidal signals? I've read that digital generators drop the max frequency when you get into saw tooth and other functions. Lastly, how do I determine how big of a frequency range I need? Do certain areas of electronics require GHz freqs while other areas are fine in the low MHz?

Title: Re: Analog vs Digital Function Generators and Frequency
Post by: SArepairman on February 08, 2014, 11:13:26 pm

DDS for 90% of things that you would want in lab function generator. It offers a good balance.

http://www.ti.com/lit/an/snoa665c/snoa665c.pdf (http://www.ti.com/lit/an/snoa665c/snoa665c.pdf)

Read table 1 (page 4) to get an idea about different methods of making sine waves.


and yea, analog/hybrid will be better at triangle and pulse then a dds in terms of speed. a 1400$ agilent meter will do triangle up to 100KHz, a used 90$ generator from 1985 will do triangle to 10MHz... but the agilent will be more stable and just nicer and more precise.