I've been using the L7660 for bipolar power for a while. Was about to order some when I noticed the company had issued an advisory to a change in the data sheet. The datasheet now recommends adding a Schottky diode between the -ve output and ground to prevent latch-up. It says to so this if the rise rate is > 2V/us.
I've one in my Gristleizer and am wondering if I need to do that - I don't really know how to estimate the rise rate.
I also noticed that it recommends to add a 1N4148 from the -ve pin to ground to prevent latch-up
I know charge pumps can be fragile beasts, so this would be nice to know!