Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Using Digital Pots

Status
Not open for further replies.

muso52

Member
Hi People,

I am lookiing at the use of using a digital pot as an analogue input (0 - 5v) to a pic.
As there is no apreciable load on the device I think all will be well but If anyone has knowledge of these devices and have some relevent comments I would welcome them.

Thanks
Willy
 
hi Willy,

As the rate of change of voltage input to the PIC's ADC will be slow, a pot of around 10K will be OK.

Some PIC d/s state 5K or 10K as being a maximum 'source' impedance if you you require a fast sampling rate.

E

EDIT:
What value of Dpot do you want to use in this application.?
 
Last edited:
Good Afternoon Eric,

The manual pot input to the PIC (at the moment) is a 10k across 5v which was recomended. So I guess a 10k digital would be Ok.

Secondly it will be 'clocked' very slowly so do not forsee any problems.

For info the dig pot is replacing a man pot used as a CC controller input to a midi pic.

Willy
 
You know that most digital pots can not have a signal beyond the supply voltage. (0-5V) man pots don't seen to care.
 
Hi Ron,

I appreciate that but the max input voltage to the pic is ....5V the same as source.

Also I read somewhere that the 'pot' bottom end has to share ground with Vcc.
Not sure if that applies to all digi pots.

Willy
 
Good Morning guys,

I hope this dosn't appear lazy but can anyone recomend a simple digital pot with the following?

Non-Volatile
10K
Non SPI (or SPI disable)
256 step if possible.
simple up/dn interface
Pdip

Thanks,

Willy
 
Digikey.com. or most parts venders, search for digital pot. You can mark no to spi. Yes to dip etc.
--------------------------------
Up/down pins & Non-V. = Maxm & Nuvoton

DS1809 is not what you want but.....
also look at MAX5128
 

Attachments

  • DS1809.pdf
    122.9 KB · Views: 193
Last edited:
Hi Ron,

Digikey.com. or most parts venders, search for digital pot. You can mark no to spi. Yes to dip etc.

Urr.....Duh Didn't think of that. Getting old(er).

Thanks
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top