LTC3779 use in non-synchronous buck-boost converter

Dear Analog team:

I select LTC3779 for my DC/DC converter, and my customer is asking me to design this IC in non-synchronous buck-boost converter.

Would you kindly answer my following problem, thank you!

1. Could LTC3779 design in non-synchronous buck-boost converter? If the answer is NO, please tell me why and what damage will cause if I design this structure.

2. Could LTC3779 design with isolate driver IC like adum3224? If the answer is YES, please kindly share how to design the circuit, If the answer is NO, please tell me why and what damage will cause if I design this structure.

3. I saw the block diagram of LTC3779, the IC compare with voltage of Vin and SW1, what purpose is this function work for? What damage will cause if Vin is always bigger than SW1? What situation will happen if this function does not work?

LTC3779 block diagram

Thank you!!

Parents Reply
  • Hi Mikee : 

    Thanks for reply.

    For Question 2

    I use adum3224 because my specification is input 700Vdc, output 350Vdc. I know it is not the standard usage of LTC3779, but I wanna try if it is possible to use LTC3779 in high voltage situration.

    For Question 3

    I saw the comparator output is connecting to buck and boost logic blocks, so I am just wondering which condition may happen, if lost those information will not make huge damage and just lost some function, maybe I do not need to use those function and I could design LTC3779 circuit without offer those information to LTC3779; or lost those information is very dangerous, LTC3779 may work abnormal and damage my circuit, so I should offer those information to LTC3779 to provide work normal.

    Also, why I need to ask Question 3, because my specification is input 700Vdc, output 350Vdc, and I can not offer SW1, SW2 and Vin signal to LTC3779.

    Thanks for your patient.