Tool/software:
Hi TI colleague:
Could you check if TPS551892-Q1 can be used as constant current source for super cap charging? see below picture
The idea is to select R4=50mohm so the constant current can be set to 1A. Based on my understanding this should work, however I’m not 100% sure if CC mode could be continuous and not tripping the short circuit protection.
As we’re freezing our design early next week, please take this as an urgent request.
TPS551892-Q1 datasheet points out:
can this happen in our application and trigger short circuit protection ?
Hi Max,
Yes, TPS551892 can be used as 1A constant current output, it will not trigger the hiccup. To trigger Hiccup protection, both two conditions need to be satisfied: (1) Vout is smaller than 0.8V, (2) the average inductor current limit is triggered, the average inductor current limit is about 4A when Vout is low. Since the output current limit is set at 1A which will not trigger condition#2, so hiccup will not be trigger, below is the test result which I did before, with 5F supercap and set at 3A output charging current, hiccup is not triggered.
BRs,
Bryce
Hi Bryce,
That's great, I revised my design as below total 50F/5V
I think it should work ok based on your test, do you see any problem?
thanks
Max
