Hi Max,

Thanks for reaching out.

We will look into this and reply to you these two days.

BRs,

Bryce

Hi Max,

What is input voltage range? Can you help provide part number of C620-C623?

What is the voltage range of the super cap?(From ?V-?V)

Regards,

Mulin

input: 6-16V

C620: EEHZK1V101XP

C621-C623: GCM32EC71H106KA03K

Supercap: 2.2V-3.0V each

Thanks

Max

Hi Mulin,

I saw you another comment:

I had a discussion with Bryce Xun (TI expert) about this part to charger supcaps, seems ok, can you tell me why is not ? 

Plese feedback about the schematic design if it is ok to use  

TPS551892QWRYQRQ1

Thanks

Max

see previous discussion:(1) TPS551892-Q1: buck-boost to charging supercaps - Power management forum - Power management - TI E2E support forums

Hi Max,

To confirm, TPS551892-Q1 can be used as constant current source for super cap charging. It is a simple solution without rich features. To discuss, I am wondering why do you choose this part instead of a BQ part? Sorry for confusing you.

About the schematic, below is my feedback:

1. Input 6-16V, output 4.4V-6V, maximum output current 1A. Set output voltage is 4.8V, when Vout reaches 4.8V, the charging will stop. I think it will be better to set Vout target to 6V. Can you share your opinion?

2.For better transient performance, recommend to use a 4.7uH inductor with Isat>8A.

3.Change R744 to 0ohm.

4. Recommended compensation parameters: R749=10k, C631=6.8nF, C632=100pF.

5.Follow layout guideline.2275.TPS55289 Layout Guideline.pdf

Regards,

Mulin

Thanks Mulin for feedback. 

We cannot set output to 6V since it is too high for supercap at worst case condition.