LTC3676-1 gets Over Heated in i.mx6 quad

Hello,

what about your schematic to give us at least a 'small' chance to work on your problem? Which power/currents are you dragging from each LTC3676-1 channel? What do you mean with 'properly'? Any scope shots for more insights?

What temperature are you measuring? Is thep art with its exposed pad soldered properly on a well done layout with enough vias and GND planes?

kind regards

Markus

Thank you for your quick reply.

1. LTC3676ELXE-1 application circuit diagram ( for I.MX6 Quad )

    https://drive.google.com/file/d/1X_UPTJWGqkW_qdJSMTTzp0lk15HQZQnA/view?usp=sharing

2. The output of the LDOs is good as shown below.
  - LDO1 = 3V Good
  - LDO2 = 3V Good
  - LDO3 = 1.8V Good

3. Buck SW2 is also good.
  - SW2 = 1.5V Good 

4. The rest of the Buck Regs.
   If any one of SW3 or SW4 is Enable, each output is output similar to the figure below.

https://drive.google.com/file/d/16mLZEsL8cdM4kflOwImarBPUdY6RsPKQ/view?usp=sharing

Thank you for your quick reply.

1. LTC3676ELXE-1 application circuit diagram ( for I.MX6 Quad )

    https://drive.google.com/file/d/1X_UPTJWGqkW_qdJSMTTzp0lk15HQZQnA/view?usp=sharing

2. The output of the LDOs is good as shown below.
  - LDO1 = 3V Good
  - LDO2 = 3V Good
  - LDO3 = 1.8V Good

3. Buck SW2 is also good.
  - SW2 = 1.5V Good 

4. The rest of the Buck Regs.
   If any one of SW3 or SW4 is Enable, each output is output similar to the figure below.

https://drive.google.com/file/d/16mLZEsL8cdM4kflOwImarBPUdY6RsPKQ/view?usp=sharing

Hello,

are you able to operate the LTC3676 without processor as load and check Vout stability in general?

Have you chosen 2.25MHz or 1.25MHz as switching frequency?

Are you able to read/write the registers via I2C?

br

Markus

Hello,

Thanks to your advice, the problem was easily solved.
The problem occurred because the Buck Reg coil was incorrectly mounted on the PCB.

The coil's resistance value was too small to check, so this happened.
The coil has been remounted and the LTC3676-1 is now working fine.

Due to the recent short problem of parts, I made a quick design change and made a new board, and thanks to you, I solved this problem well.
Thank you again.

kind regards

Coupler