5V Boost Converter

Hello All,

I'm building a 5V Boost converter for single cell lithium batteries based on the TPS61202 data sheet here. I want to use this as a power source for the Aixiz linear driver to drive a red diode. The 5V output will also be used in other projects.

The schematic is found below.



Can anyone check it over for me to see if I've done anything wrong or if there are any potential problems? I want to run ~500mA off this circuit.

I used the max allowable inductor value of 4.7uH. The inductor is rated at 1.2A.

Lmin=Vin*0.5us/A
=4.5*0.5us/A=2.25uH

The under voltage protection UVLO pin is set to around 2.6V.
Vuvlo=0.25
Vin min/Vuvlo=R3/R4+1
R4 should be around 250k
Vin min=2.6
R3=((2.6V/0.5V)-1)*220k=2068k~2M

If nothing is wrong I'll start designing the board.

Edit: Forgot to add reverse polarity protection. I'll add that in soon.

Why are you using 4.7µH? The datasheet says "Using 2.2 μH is recommended anyway
for getting best performance over the whole input and output voltage range."

You know there are completed 5V boost circuits on ebаy for $1 each, right?

Cyparagon said:

Why are you using 4.7µH? The datasheet says "Using 2.2 μH is recommended anyway
for getting best performance over the whole input and output voltage range."

You know there are completed 5V boost circuits on ebаy for $1 each, right?

Click to expand...

I think for my max voltage I need at least 2.25uH. 3.3uH would work then?

Regarding the ebay circuits, most of them are from China. Are they reliable?

This would work I think. Although I'm looking for the smallest package I can find.

Edit: I'll try the ebay one first before making one, thanks!

Apocalypse said:

Although I'm looking for the smallest package I can find

Click to expand...

There's a place I go to extensively for converters and they are US designed and built, in fact their turning centers in Las Vegas.

Pololu Robotics and Electronics
www.pololu.com

Here's a list of their Boost only and Buck-Boost Modules, see if these might help
https://www.pololu.com/category/132/step-up-voltage-regulators
https://www.pololu.com/category/133/step-up-step-down-voltage-regulators