I see the XC9128 is a bit difficult to source - I can find small quantities of the XC9128D part in stock, but none of the B variety. (These differ in the “integral protection” - not sure how important that is to the design)
I have had a bit of a difficult time finding a suitable replacement - the best I could come up with was the TPS61097A-33 which is certainly more pricey but otherwise is close - unfortunately it doesn’t appear to source enough current though. Any thoughts on other alternatives or the suitability of this TI part? Or any ideas if the integral protection can/should be skipped?
It’s been a while since I looked into it @scottm, (having the same observations/concerns as you). I can report though that I have been using the XC9128D in a Nora style design for a while now with no apparent issues.
I just found some other TI parts that can handle larger currents, but don’t have the bypass feature (for example, the TPS6106) That seemed to be one of the better features of the design (given the voltage regulation on board the module).
It is a bit hard to source. I found a sales rep in NY that claims to be able to get any quantity of Torex parts. I could pass along his contact info if you like. I dislike using parts that I can’t get whatever I need immediately though. There are a lot of new regulators coming out, though I admit I use the TI TPS62233 and TPS62162/72 almost exclusively. I like rechargeable LiPo’s for battery designs, especially with the new Qi wireless charging standards and chips becoming really easy to use.