I am posting my KiCad schematic, for my revised personal choices, for Jay’s Dynamic E-Load. Extra proofing, suggestions and comments are v-e-r-y welcome. I will be ordering the board, soon.
The only other thing that has been suggested is adding a switch, to disable some of the MOSFETs, for smaller loads. I may do that.
I would really appreciate someone open the Kicad files and confirming that the custom libraries work.
My choices, based on my stocks, or purchase preferences, are
- Dual power supply
- Dynamic, including an auxiliary input, for a Function Generator
- TLV171 Op Amps
- IRFP230 MOSFETs
- LT1019_2.5v Voltage Reference
- The MOSFETs will be wired directly to the PCB and abutted to the heat sink
The auxiliary input, for the function generator, is a new feature option. I researched it, through an independent thread.
https://www.eevblog.com/forum/projects/hacking-a-dynamic-electronic-load-circuit-to-use-an-external-function-generator/It is based on
- Injection of the FG signal, before the attenuation pot
- Signal diodes, in the controlling op amp and the driving op amps, placed in parallel to the feedback circuit.
- A 50 ohm termination resistor
I do not have the knowledge, to create this feature… I am thankful to those that helped design it.
Kia, over at TI, has modeled the circuit and it should be stable.
I am using a trick, to be able to use a cheap 100 x 100mm Chinese board… I will cut the board into two pieces, overlap them and tie the traces together, with TH pins, to get the length that I need. My heat sink is very long. So, some of the repetitive symbols, on the schematic, are to facilitate that. The remaining netwire connections will be made, by connecting the boards.
![](https://www.eevblog.com/forum/projects/electronic-load-project-ltv171-irfp250-with-kicad-files/?action=dlattach;attach=528281)
I am, presently, writing a tutorial, for this process and will release it, soon. The trick is in how to make the exact placement of the upper and lower pads so that they will line up, perfectly.
Special thanks to Jay Diddy B, Kleinstein, JS, Kia and all the others, who have so graciously helped me learn, understand and create.
Jay’s thread, with various versions; Post #144
https://www.eevblog.com/forum/projects/dynamic-electronic-load-project/125/You are free to make any and all use, of the files. However, in doing so, you release me from absolutely all liability. I am not an electrical engineer. I do not guarantee that there are no mistakes. You must verify absolutely everything, for yourself. I did not design the operational circuit.
![](https://www.eevblog.com/forum/projects/electronic-load-project-ltv171-irfp250-with-kicad-files/?action=dlattach;attach=528287)
![](https://www.eevblog.com/forum/projects/electronic-load-project-ltv171-irfp250-with-kicad-files/?action=dlattach;attach=528293)