TPA6139A2: Thermal performance

Vincent Chen64988

Part Number: TPA6139A2

Hi Team,

My customer is designing TPS6139A2 in his schematic and would like to know the thermal performance when the worst case happen.

The supply voltage is 3.3V, in the worst case the max. limited output current is 60mA. The power dissipation is 3.3V*0.06mA*2ch=0.396W. RθJA of TSSOP package is 130°C/W, so the Tj=0.396*130+25=76.48°C (room temp. is 25°C).

Please comment is my understanding is correct or not.

Thanks very much.

Vincent Chen

over 3 years ago

0 Justin Beigel over 3 years ago

TI__Mastermind 18545 points

Hello Vincent,

Your calculations use the output power rather than the power dissipated in the device to calculate the temperature. It would be better to consider the supply current for this calculation.

Best Regards,

Justin Beigel

0 Vincent Chen64988 over 3 years ago in reply to Justin Beigel

TI__Expert 4480 points

Hi Justin,

Since customer is in schematic design phase and not able to measure the supply current of the device. Is there any equation to calculate Tj at room temperature of 25°C when TPA6139A2 is operating at most worst case?

Thanks a lot.

Vincent Chen

+1 Justin Beigel over 3 years ago in reply to Vincent Chen64988

TI__Mastermind 18545 points

Hello Vincent,

You can use the supply current listed in the datasheet (25mA) for an estimate. This is with no load so there would be some variation with whatever load your customer is going to have but this still gives a rough idea of the temperature of the device (35.725°C using the same formula as above).

Best Regards,

Justin Beigel

0 Vincent Chen64988 over 3 years ago in reply to Justin Beigel

TI__Expert 4480 points

Hi Justin,

Got it, thanks a lot for your support.

BR,

Vincent Chen

0 Justin Beigel over 3 years ago in reply to Vincent Chen64988

TI__Mastermind 18545 points

Hello Vincent,

You are welcome.

Let us know if you have any other questions.

Best Regards,

Justin Beigel

Audio

Audio forum

TPA6139A2: Thermal performance