TPS785-Q1: TPS78512QKUVRQ1

Semih Senyuz

Part Number: TPS785-Q1
Other Parts Discussed in Thread: TMS320F28388D,

Hello Sir,

In my design I try to convert 5V-1.2V for supplying my TMS320F28388D core.So I have found TPS785 fixed 1.2V LDO.
For 0.7 source current do you think TPS785 could be efficient way?Or do you have any recommendation to supply it.

Thank you for your interest in advance
Semih Senyuz

over 1 year ago

0 Erin Thibeault over 1 year ago

TI__Expert 6570 points

Hi Semih,

I think TPS78512QWDRBRQ1 is a good selection for this application.

Is AEC-Q100 a requirement for your application?

BR,

Erin

0 Semih Senyuz over 1 year ago

Prodigy 70 points

Hello Erin,

It is acceptable whether TJ or TA 125 celcius no problem unless it is 85 celcius.But as i said, we concerned about efficiency and temperature of the device and unfortunately i couldn't simulate it.If I sink 0.7A 5-1.2 = 2.3.8 * 0.7 = 2.66 W, I don't know device can handle it.If you evaulate on this perspective I would be appreciate.

Thank you for your interest
Best Regards
Semih Senyuz

0 Erin Thibeault over 1 year ago in reply to Semih Senyuz

TI__Expert 6570 points

Hi Semih,

TPS785-Q1 is rated to operate from -40 to 150ºC.

The junction to ambient thermal resistance (R_ΘJA) for the DRB package is 59.5ºC/W. So at 5V in, 1.2V out and 0.7A, the device will heat up by ~158ºC (2.66W*59.5)

The KVU package might be a better alternative here. The junction to ambient thermal resistance (R_ΘJA) for the KVU package is 31.6ºC/W. So under these same conditions, the device will heat up by ~84ºC (2.66W*31.6). Thus, I recommend TPS78512QKVURQ1 instead of TPS78512QWDRBRQ1.

You can improve thermal performance per this app note: An Empirical Analysis of the Impact of Board Layout on LDO Thermal Performance

BR,

Erin

Power management

Power management forum

TPS785-Q1: TPS78512QKUVRQ1