TMCS1100: TMCS1100 Bandwidth concern

Willy Su

Prodigy 10 points

Part Number: TMCS1100
Other Parts Discussed in Thread: TIDA-010062

Dear Team,

I see TIDA-010062 using TMCS1100 for the PFC current loop control

The PFC stage switching frequency(Fsw) is around 100kHz.

Base on my experienced, the control loop bandwidth need to be 10*Fsw.

So the TMCS device should be around 1MHz to fulfill the job here.

May I know the reason why you choose this device here and the system can still work well?

https://www.ti.com/lit/ug/tiduet7c/tiduet7c.pdf?ts=1628475650633&ref_url=https%253A%252F%252Fwww.ti.com%252Ftool%252FTIDA-010062%253FHQS%253Dsys-ind-null-21Q3IndustrialPower_loctrweb-exah-ON24-foc_event_rmd-tw

Kevin

over 3 years ago

0 Mitch M over 3 years ago

TI__Mastermind 20565 points

Hello Kevin,

Thank you for using the TI forum. I am reaching out to the team who created that TIDA to see if they have any insight for you. I will reply tomorrow with any updates.

0 Mitch M over 3 years ago in reply to Mitch M

TI__Mastermind 20565 points

Hello Kevin,

It actually looks like the answer to your question is right in their document:

0 Desheng, Guo over 3 years ago

TI__Expert 6190 points

hi, Kevin
If you are using the current sensor do CCM PFC current control, generally it is only 2kHz bandwith (current loop), so you do not need to sense the switching current. Somebody choose 1MHz hallsensor, they may hope to do OC protection. But LMG341x has OCP integrated already.

Sensors

Sensors forum

TMCS1100: TMCS1100 Bandwidth concern