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DIY Stompboxes => Building your own stompbox => Topic started by: todd.dukes on April 16, 2019, 09:21:41 AM

Title: MAX9722 will not work without 1uF on PVss
Post by: todd.dukes on April 16, 2019, 09:21:41 AM
I don't know how I missed in from the data sheet, but I had a lot of trouble getting the charge pump to work on the MAX9722. They do have at least one schematic that shows a 1uF cap from PVss to ground (pin 7 on TSSOP)

I hope this helps anyone wanting to try this chip.

It works well with this cap. It doesn't work at all without it. I am using this with the 78L05, but have some 7805 on order to use in the final project. The TSSOP is small but I got it soldered ok using the Kester 186 and some solder wick.

Here is the second one I soldered:

(https://i.postimg.cc/7fySd2Qq/20190415-094935.jpg) (https://postimg.cc/7fySd2Qq)