Hi,
I am using the TPS61500 led driver for a lighting application. I have to drive 20 LEDs with an output voltage of 11.3V and a current of 400mA. I used an 8,2uH 3A inductor with a frequency of 600kHz. If I power the driver with 4V, I have an efficiency of 84% and the temperatures of the inductor and the driver are around 55 ° C. If I go down to 3V in input, the efficiency drops to 69% and the temperatures of the inductor and the driver rise above 90 ° C. When temperatures rise above 90 ° C, I start to see the fliker and the TPS61500 limits the output current, the thermal protection certainly intervenes.
What do you recommend to increase the efficiency on the 3V input?
I would like to know if there is a spreadsheet of the TPS61500.
To follow the schematic:
Test Report Table:
Best Regards
Davide Facchini