TLV62150 Efficiency Problem

Your schematic follows the D/S and is ok. Can you post your raw measured efficiency data and your inductor part number?

Dear Chris

We have used inductor from Coil Craft and its manufacturer part number is XAL4020-222MEB. Please find the attached datasheet for the same.

My INPUT is : 12 V 

Current Consumption by my system is :  150mA

Output of My buck converter is 5V which i am giving to drive LEDs, i have 8 x 8 LED Matrix .

I am also attaching datasheet for LED (APT1608SURCK)  as well for your reference. Each LED is Drawing 24mA.xal4000.pdfAPT1608SURCK.pdf

I am calculating that raw measured efficiency is around 60-65%, which should be 80-85% as i have pulled FSW to Low.

Thanks

Krunal Shah

I don't understand how you are using your circuit, configured to give 5Vout, to drive LEDs? For example, if you have 8 in series that would be at least 16V applied to the string based on their forward voltage.

In any case, to measure efficiency we need to measure (with a DMM) Vin, Iin, Vout, and Iout per this app note Figure 5: www.ti.com/.../slva236.pdf

Dear Chris

Please find the attached LED matrix which i am driving. Do i need to change Inductor Or Capacitor? 

My Software logic is such that i will keep every RAW on and keep column switching to on/off led

I will test the voltage as you said using DMM and let you know the result

Thanks

Krunal SHah

Dear Chris/Team

Waiting for your reply on the query.

Thanks

Krunal Shah

Were you able to measure the raw values that are needed to compute efficiency?

As well, the above setup looks like it would have too much voltage drop across the LEDs. Assuming they only need 3V or so, then this is 2V which must be lost. Lowering the voltage to 3.6V or so would likely reduce the input power.