TPS563249: Questions regarding TPS563249

Hiroyuki Asaga

Part Number: TPS563249

Hello,

I would appreciate any feedback to the questions below regarding DCDC converter TPS563249.

Currently the device (TPS563249) is not performing thermally at the specification it needs to perform at.

Is it possible to lower the heat resistance by adjusting the heat dissipation pattern in a certain way? If possible, is there any material or test data that can be used as a guide for this?

Also, when using WEBENCH simulation for this device, there is a parameter ``ICThetaJA Effective`` with a value of 51C/W. What is exactly is this parameter and how is it measured? For instance, what kind of PCB is this measured on? Is it measured based off of EVM board or JEDEC standards?

What is the difference between RθjA from the data sheet and ``IC Theta JA Effective`` displayed on WEBENCH?

For reference. the conditions while using this device can be found below:

・Max Output Current：1.15A

・Ta(max)：60℃

・Input Voltage(TYP)：15V

・Input Voltage(MAX)：16.8V

・Output Voltage(TYP)：3.318V

・Output Voltage(MAX)：3.422V

Your help is greatly appreciated!

over 4 years ago

0 Vincent Zhang(BSR) over 4 years ago

TI__Expert 4795 points

Hi Asaga,

ICThetaJA Effective is based on EVM Board(TPS563249EVM-031). RθjA in datasheet is based on JEDEC standards boards.

I suggest you to refer to application notes to better understand different thermal resistors. (

)

What's the temperature you measure at your condition? What's your PCB size and thickness? Is there any high temperature device near TPS563249?

0 Hiroyuki Asaga over 4 years ago in reply to Vincent Zhang(BSR)

TI__Intellectual 1735 points

Hi Vincent,

Thank you for your response and material.

Customer is currently simulating through WEBENCH before considering device.

Is there any information regarding lowering heat resistance specifically through changing the heat dissipation pattern for this device?

Thank you,

Hiro

0 Vincent Zhang(BSR) over 4 years ago in reply to Hiroyuki Asaga

TI__Expert 4795 points

Hi Hiro,

We can lower effective heat resistance by changing the layout. For example use 2oz 4layer PCB, add vias near the IC, etc.

Hope it helps.

0 Hiroyuki Asaga over 4 years ago in reply to Vincent Zhang(BSR)

TI__Intellectual 1735 points

Hi Vincent,

Thank you for the informative feedback.

Is there any additional recommendation you can provide regarding board size, ground trace size, etc.

Also is there an application note or some material similar to an application note for TPS563249 or/and TPS563249EVM-031.

Any help is greatly appreciated.

Thank you,

Hiro

0 Edwin Zang over 4 years ago in reply to Hiroyuki Asaga

TI__Expert 6425 points

Hi Hiro,

below link is TPS563249 EVM user's guide which includes layout, BOM, board size and some waveform. i hope it's helpful for you.

TPS563249EVM-031 17-V, 3-A, Regulator Evaluation Module

BRs,

Edwin.

Power management

Power management forum

TPS563249: Questions regarding TPS563249