Hi,
I confirmed that there was a short between INTVCC and BST of LT8620. Therefore, I think the internal diode may be broken.
If you have any experience with this cause, please let me know.
Best regards
LT8620
Recommended for New Designs
The LT8620 is a compact, high efficiency, high speed synchronous monolithic step-down switching regulator that accepts a wide input voltage range up to...
Datasheet
LT8620 on Analog.com
Hi,
I confirmed that there was a short between INTVCC and BST of LT8620. Therefore, I think the internal diode may be broken.
If you have any experience with this cause, please let me know.
Best regards
Thanks for the information. One possible cause may be the overvoltage on the BST pin. Another thing to check is the BST cap on the pin. A local 0.1uF cap is recommended to be close to the IC.
Best regards,
Andrew
Hi Andrew-san,
Thank you for your reply.
I confirmed the BST cap on the pin. But I didn't confirmed value of between BST and SW. I will confirm this value.
I also have another question. Could LT8645S apply above possibility.
Because LT8645S was confirmed same problem. But datasheet has not information. if you have information, please let me know.
Best regards
Hi Andrew-san,
Thank you for your reply.
I confirmed the BST cap on the pin. But I didn't confirmed value of between BST and SW. I will confirm this value.
I also have another question. Could LT8645S apply above possibility.
Because LT8645S was confirmed same problem. But datasheet has not information. if you have information, please let me know.
Best regards
My pleasure to help. It depends on the application. LT8620 and LT8645S have very similar voltage range. LT8645S has higher current rating. The LT8645S belongs to the silent switcher product family with extremely low noise level. There is no need for BST cap, which is integrated into LT8645S.
I recommend to compare the schematic and PCB layout with the demo board design.
Best regards,
Andrew