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General Category => General Discussion => Topic started by: cheerio on December 31, 2012, 17:49:25 PM

Title: digital poti question
Post by: cheerio on December 31, 2012, 17:49:25 PM
Hi,
i need a digital poti that survives ~24V on its resistor terminals. All digital potis i found do only survive the operating voltage of the chip on their resistor terminals. Are there any digital potis for my application or do i have to make a resistor array myself?
The voltage applied to the resistor terminals is between 0V and 24V. I found some potis that work with ~30V supply voltage but i would like to use ~5V supply voltage and still use 0V-24V on the resistor terminals? any chance?

thank you in advance
Title: Re: digital poti question
Post by: kam on January 02, 2013, 10:52:19 AM
I've never met such a digital pot! Maybe you can interface it with a transistor?
Title: Re: digital poti question
Post by: _pike on January 02, 2013, 11:56:36 AM
Check on page 18......
i Think that will suit your requierments.

http://www.analog.com/static/imported-files/data_sheets/AD5290.pdf
Title: Re: digital poti question
Post by: cheerio on January 02, 2013, 18:33:30 PM
Check on page 18......
i Think that will suit your requierments.

http://www.analog.com/static/imported-files/data_sheets/AD5290.pdf
was looking at this already. the problem here is that the input voltage can drop to <1V and the poti won't work with that afaik. Thats why i would love a fixed supply voltage. i think i will make a resistor array :/