single cell dc/dc converter PCB BC327 PNP

this is a dc/dc converter PCB I designed a few years ago. One transistor, two coils, and some passive components. It is adjustable. prototype photo actual PCBs are infrared soldered. New revision of the dc/dc converter PCB! It has been tested from 1.2 volts to 5 volts input range. Small PIC circuits can be powered directly from 1.2 volts battery with … Continue reading

switching regulator test circuit (based on LM317)

  test circuit for switching power supply. Not using a ready-made IC! It is based on PNP transistor, and coil from a CFL. Efficiency is not so good but not too bad, the transistor does not heat up, dumping 6 volts into 22 Ohms, from 20 Volts. The circuit makes some noise! And it is not the latest technology…actually based … Continue reading

TL494 SMPS – switching mode power supply

this is a prototype I have built for research purpose. Recently I have learned how to use MOSFET technology. 1x VGA cooler is used together with IRF9540 p-channel MOSFET. 20V/100A welding transformer is used as voltage source! With no load, DC output is about 60V. 1x 12V 50W bulb for testing. Actually today I tried a second bulb in parallel … Continue reading

dc/dc converter, new PCB revision available

  redesigned the PCB! -no patches -high efficiency LED via 4.7k resistor -variable resistor to adjust quitescenct current -robust diode -imprint on the PCB for input/ouput, + and – this PCB can power small PIC circuits directly from 1.2 volts battery, as well it can replace 9v batteries, for instance it can generate small 12v currents from 2x AAA cells. … Continue reading