From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive!
7 posts • Page 1 of 1
- Super Deluxe Wiggler
- Posts: 1850
- Joined: Tue Aug 07, 2018 11:20 am
- Location: Portland, OR
I asked about the 2164 as a current sourse for a triangle VCO before and was advised by Neil Johnson that's it not ideal to use that way, and as per the data sheet is best kept as current sink, like in the expo converter in the ssi data sheet. (Must confess the reason were above me however.)
the 2164 should work ok. perhaps neil assumed you were going to drive the capacitor directly, but if you use an opamp integrator sinking and sourcing should both be fine. the input stage has DC accuracy issues due to offset voltage/current, but i dont think its a show stopper. but, the 13700 is a more widely available part, and is cheaper. it also allows you to more accurately control the expo converter. theres pros and cons to each.
Of the parts suggested above, which is least likely to go out of production in the near future? (i.e. is commonly used in mass produced systems like mobile phones, home appliances, etc. ?)
neither are widely used parts, but are both likely to be around for quite some time. i feel like the LM13700 might outlast the 2164, but thats still going to be at least another 20 years from now. a discrete transistor approach would be the only one guaranteed to not go out of production, as you can swap in different transistors as needed.