Monthly Archives: April 2014

LT-1303-5 with new inductor


Based on some ideas in the eevblog forums, I replaced the TDK inductor I used in the first videos with a Sumida RCH-855np.  The sumida specifically says…

• Ideally used in Printers, LCD TV, DVD, Copy Machine, Mainboard of the compounding machines etc. as DC-DC Converter inductors.

Since the TDK data sheet was a bit ambiguous and stated it was for “Power lines” there was a theory that the TDK may have actually been a choke.  Turns out the results show pretty much the same performance.  I was unable to get above 67% efficiency.  I would really like to see someone do better with this chip on video.

I think my next step will be to but the Adafruit kit for the minty boost, which uses the LT1302 chip in its design.  I am curious to see the results on a professionally designed pcb with a similar chip.

Followup to the LT1303-5 DC to DC Boost Converter

Per  many recommendations by the forums users over at, I made a few modifications to the boost converter circuit.  I increased the size of the output filter cap, and reduced the length of the conductors.  I picked up 5% additional efficiency but still fall short of the 80+ percent in the data sheet.

LT1303 Efficiency dataRevised for 17mA out.


LT1303-5 two cell to 5V Boost converter supply

In this video I put together a small circuit to test out the LT1303-5.  I am not getting the efficiency numbers in the data sheet.  See the attachment below for the figures I recorded.  Granted I don’t know what Im doing, so if you spot the issue, please let me know… and be gentle.  Thx, JZJ



LT1303 Efficiency data

LT1303-5 boost regulator datasheet