Search results

  1. Silvio

    Variable dual PSU for Lab use

    Here I am posting a dual Psu for use in the lab. This power supply was intended to be run with a linear regular after the smps. However it can be used as it is. The voltage range is between 4v-30v. In my version I added a dual linear regulator which the input follows with about 6v more than...
  2. Silvio

    Calculation of snubber resistor and capacitor and also Gate resistor calculation.

    In the PDF file below one will find how to calculate snubber components and also how to calculate the gate resistor for a mosfet or IGBT so that the dead time can be calculated correctly and the transistor will switch in time.
  3. Silvio


    Here is guide to winding a safe transformer for SMPS. In this article you will find good guide lines to help you out making a safe transformer and adopt a good practice how to wind transformers with good coupling, It will also look a little bit on mandatory clearances in PCBs used for off line...
  4. Silvio

    Making litz wire at home

    Here you will find my experiences when making litz wire at home based on information that I gathered through the net. I also examined and experimented myself with several types and these are my findings. Cannot upload zipped file of 1.16MB If anyone wish to see this file I can post it through...
  5. Silvio

    Best heat transfer insulator

    I encuntered a dilemma what to choose as an insulator behind a power transistor. Is it a silicone pad, a mica pad or a ceramic pad. Which of these deliver the best heat transfer to the heat sink? Which of these has the best electrical insulating properties? And lastly Safety. All opinions are...
  6. Silvio

    Llc hb smps 2000w

    Here is an smps that I have been working on for the last 6 months. This is my first prototype and apart from the simplicity this smps has a lot of features for it to work on an audio amplifier. 1) Over input voltage protection with a Varistor 2) A good input filter to reduce EMI as much as...
  7. Silvio

    Compact Aux power supply for smps

    Here I am presenting an auxiliary power supply meant to be fitted with a SMPS of half or full bridge. The output voltage was chosen to be 17v which is quite ideal for this purpose. However this voltage can be varied to suit the particular need . The TOP221P chip is utilized as this comes in...
  8. Silvio

    Choosing the right output inductor for smps

    Dear Members I have been experimenting with SMPS for quite a while now but I have found that when choosing output inductors a few problems occurred especially regarding voltage drop and the output inductor getting hot. I have been using Excellent IT during my design for half bridge topology...
  9. Silvio

    IR2161 smps

    Hello fellow friends, has anyone tried this chip as an amplifier smps? I can see that it has a soft start and also a short circuit protection. I found someone on youtube comparing the IR2153 with this chip. unfortunately it was in Russian and did not understand a word he said. The IR2161 is...
  10. Silvio

    Audio smps 700w (IR2153)

    Audio smps 550 watts 700watts peak Here is an audio half bridge smps that can be altered in quite a lot of ways. This smps was designed in such a way that different drivers can be adopted, also that different protection circuits can be adopted. The one presented here is with a current limiter...
  11. Silvio


    Hello fellows, here I am presenting my new universal SMPS. This Power supply is of half bridge topology. The reason it is called Uni-Smps is because it can be triggered with different drivers as the oscillator board is detectable with a pin header. There is adequate space on the driver board...
  12. Silvio

    Switching power supply design by Abraham L Pressman

    Does anybody know where to download this book or does anybody has it? My Mail address is Thanks Silvio
  13. Silvio

    1000w smps based on LUDO3232

    Hi fellas, I am building a smps based on Ludo 3232 but with a different arrangement. I would like to take some comments about the arrangement of the pcb layout and if the spacing is adequate. The pdf is attached please take a look.
  14. Silvio

    IR2153 350 watt RMS Audio SMPS with current limiter --based on Borysgo2 design--

    Hi everyone, here I am presenting a tutorial and explaining my hard work in building a successful working SMPS. I being a newbie myself in this field of work had to learn things the hard way and the way to it all is explained in the PDF attached. All is found in it so one can replicate it. I...
  15. Silvio

    Isolation transformer

    Hello everyone I need a soft start for my new isolating transformer. This is to power the whole bench when working on mains etc. The capacity is around at least 2.5Kw at 200volts output. This transformer used to power an amplifier of 6kw and it had two of these. Does anyone have a schematic...
  16. Silvio

    Help needed understanding Excellent IT software

    Dear All, Regarding the understanding of Excellent IT software I have a few questions how to use this software. The maximum flux density of the core material selected in my case (N87). When imputing the frequency and also the core material this changes automatically. 1) Does this box...
  17. Silvio

    Confused regarding ferrite core power output

    Dear all, I am a bit confused regarding power output of ferrite core transformers. According to data sheets and comparison what everyone else did by reading forums over here it was found that though data sheets (TDK Epcos cores) say for example an ETD 49 can give around 700 watts at 100Khz in...
  18. Silvio

    HELP NEEDED to calculate a snubber for the primary of smps

    Hi, can anybody help me calculate the values of a snubber needed for the primary winding of a half bridge smps? At the moment I have 680pf 1kv with a series resistor of 150 ohms at 3watts but its getting rather hot! Input voltage = 230 volts AC Input dc voltage at transformer Primary is 155 Vdc...
  19. Silvio

    Conversion of ATX power supply (heat dissipation problem at low voltage high current)

    Dear All, lately I converted a computer ATX power supply rated at 400 watts. it is intended to work as a dual variable power supply from 1-30vdc at 5 amps 1) The topology is half bridge. 2) The chip is the TL494. 3) The ferrite transformer is re wound to give 2 secondary windings of 34 volts...