Prototyping TI TPS61097 Boost Converter

  • Hero Member

    So, while waiting for the official boost module I decided to try out the samples I got from TI a while back. The TPS61097 is a 5-Pin SOT-23 Package. I soldered two of them on typical "SOT23 to DIP adapters" found on Ebay. One was then put on a breadboard and one was permanently soldered on prototype pcb. Despite my best efforts I'm out of my depth here and cannot get these circuits to work. I tried the EN pin connected to Vin directly and using a 10k resistor. I have some ceramic caps (DIP) and shielded inductor (SMD) that I've tried.


    My DMM tells me that there is an output voltage but it seems to slowly dissipate, counting down from around 3V or so as if the chip just locks up. Tried connecting a fresh out of the box Arduino Pro Mini and it turns on the red power led but it cannot boot hence no blinking green led.

    Is there some way to troubleshoot the chip itself without building the entire circuit and introducing more variables? Could I have simply burnt the chip while soldering? I didn't have the right diameter solder at the time so I may have mucked about too long to get rid of the excess, and still no liquid flux to expedite the process as suggested in most tutorials. Or is the input voltage too close to the limit? I get 3.26V from two new AA. Pretty lost here ...

  • What are you using for the inductor (L1)? The spec sheet indicates that something in the 4.7 microHenries range should work.

  • Hero Member

    @soward I use some sort of no-name 10 uH 12mm (I know, stupidly big) shielded inductor from AliExpress. Looks a lot like these, fairly bulky and heavy:

    Haven't done more than go over it with the continuity tester to see that it didn't have some sort of rudimentary inside damage. I also tested the capacitors, they were close enough to 10 uF but I did some surprising minor variation that can't be blamed on the DMM. Random Ebay caps are probably not a good idea if you need spot on values. But they did seem to work.