Digi-pots

[Spruce_Moose]

Has anyone had any experience using digital pots? I'm currently trying to find my best option for 100k. I don't think a vactrol will have the accuracy I'll require. Cheers

[pete_currie]

I've got some Motorola MCP41100's in the draw. Haven't got around to using them yet.
They have an SPI interface, amd I intend on controlling them with an AVR microcontroller.

What are you using them for? Controlling them with?

[Spruce_Moose]

The ATmega328 ..still in the early stages of learning how to use it. The only cool thing I've managed to do so far is this: http://www.youtube.com/watch?v=KZ-0Y7WETCc

[pete_currie]

I am planning on using mine in conjunction with a rotary encoder.
The encoder is used to control the value of the digital pot.
This is itself is fairly redundant, but it means that digital pot setting can be saved and recalled.
It allows you to have presets in an completely analogue circuit.

[Spruce_Moose]

Cool! I'm trying to track down something non-volatile with a 1% tolerance and a range of 100k ohms. From what I can understand, it's going to need enough steps that if I also want to use it with a range as low as 10k it's not going to have audible steps. Also, I think the pot input voltages can't exceed the Vdd.. so if I can only find those specs in a digi-pot with a 5v supply, I might have to look into how commonly that's exceeded in general potentiometer usage in pedals. All these spec. sheets are making my brain mushier

[capt abaham]

wow props awsome!