Hi
My customer use TPS73HD301 to power two C2000 28374, the input voltage of both channel is 5V, and channel 1 output 1.2V, channel 2 output 3.3. Can both channels afford 750mA current load simultaneously？Do you have test waveform？Thanks.
Best regards
Chen
Hi Chen,
I am assuming the customer is operating without air flow in the system.
If so, it looks unlikely that both can provide this level of current simultaneously at these voltages, even if the ambient temperature is 25C (room temp).
Please see this snapshot from the datasheet.
(5-1.2)*0.75 = 2.85W
(5-3.3)*0.75 = 1.275W
2.85W + 1.275W = 4.125W, which is higher than 2.9W or 3W with no air flow.
At >4W it will be very hard to dissipate the heat and stay within the manufacturer specification.
I would recommend dropping the 5V across a 3rd LDO going into the 1.2V output.
A low cost, industry standard like the LM317 will be an easy choice.
Thanks,
- Stephen
