TPS65235: LNB voltage regulator_power consumption

Samuel Sales

Prodigy 10 points

Part Number: TPS65235

Hi,

Could you tell me the worst case power consumption in certain modes of the TPS65235 and how this could be calculated.

e.g. 12V input/ 18Volts output/ at 600mA load/ with diseqc. 140mΩ power MOSFET running at 1 MHz

Thanks,

Samuel

8 months ago

0 Lucia Gao 8 months ago

TI__Genius 16580 points

Hi Samuel,

Thanks for reaching out! For the power consumption, you can refer to the efficiency curve/ test with EVM board. Could you please let us know working condition of your application? Vin range, Vout, loading, Fsw? We can share you the result according to your application.

Thanks!

BRs

Lucia

0 Samuel Sales 8 months ago

Prodigy 10 points

Hello,

Yes I was able to make a rough calculation based on datasheet graphed out efficiency of 89% @12V input 18 output 600mA. Device power consumption/loss was calculated as 10.8W - (10.8*0.89) = 1.18W. Is this correct? How would Fsw affect this figure, understanding that Diseqc is generally a short burst not affecting overall power.

Thanks,

Samuel

+1 Lucia Gao 8 months ago in reply to Samuel Sales

TI__Genius 16580 points

Hi Samuel,

Thanks for your feedback. For calculating the power consumption, you can first calculate total power consumption of the device and minus the loss of the inductor. For example here the total power consumption is 18*0.6/0.89-18*0.6=1.334W. Then please minus the loss of 4.7uH inductor. For different Fsw, it will have an effect on the switching loss, you could test with EVM board to get the loss.

Thanks and kindly let us know if there is anything unclear.

BRs

Lucia

0 Samuel Sales 8 months ago in reply to Lucia Gao

Prodigy 10 points

Thank you. that's clear. Your total power and efficiency includes the inductor.

Thanks,

Samuel

0 Lucia Gao 8 months ago in reply to Samuel Sales

TI__Genius 16580 points

Your welcome!

BRs

Lucia

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TPS65235: LNB voltage regulator_power consumption