Simulation Files

Here you will find simulation files for some of the circuits in the my RSGB book ‘Power Supplies Explained’ as well as others that will accumulate over time. They are in the popular Simetrix format. A free ‘elements’ version of Simetrix is currently available from their website. Simetrix says:

“SIMetrix/SIMPLIS Elements is our demonstration free version that can be used without license or copying restrictions, for personal, educational and business use.

Virtually all features of the full version are enabled but we do restrict the size of the circuit that can be simulated. These limits are generous enough for them to be used for real work and we are happy for our users to do so. SIMetrix/SIMPLIS Elements comes with the fully featured schematic editor and waveform viewer found in the full version. SIMetrix/SIMPLIS Elements is available for Windows® systems only”.

I also recommend you look at a web based design tool - I use this for all my schematic drawing as it is easy, flexible and can output in .pdf format for printing or further conversion to other formats. pdf files are vector graphics files which means they are small and are perfect quality whatever the scale unlike bitmap files like .png or .jpg. It will also output .svg and bitmap files but I have had less success with these formats. Easy EDA has a PCB layout and simulation feature which I haven’t tried to date.

SPICE simulation files are text files. If you click on the Figure links below you will see text. Copy this to a text editor like notepad and save it with a .WXSCH extension. It should then open with SIMETRIX (change 2.1 to .sxgph

Figure 1.3:  Simple linear regulator dissipates 11.2W

Figure 2.1: Mains transformer and bridge rectifier

Figure 2.10: Full-wave voltage doubler

Figure 2.17: Resettable electronic ‘fuse’

Figure 3.1: Simple Zener stabiliser

Figure 3.5: A high power Zener equivalent

Figure 3.6: High power shunt stabiliser with NPN transistor

Figure 3.7: Dual output shunt stabiliser

Figure 3.8: TL-431 IC as a Zener diode

Figure 3.10: A high power Zener equivalent using a TL-431

Figure 3.12: Simple series linear regulator

Figure 3.13: Series Darlington regulator

Figure 3.14: Series regulator with paralleld transistors

Figure 3.15: Series regulator wit constant current limiting

Figure 3.17: Series regulator with foldback current limiting

Figure 3.18: Closed loop linear regulator

Figure 3.20: Series regulator with adjustable output

Figure 3.21: Remote sensing

Figure 3.22: LM317 adjustable regulator

Figure 3.25: General arrrangement of three terminal regulators

Figure 3.26: Increasing output voltage by 0.6V

Figure 3.27: Increasing output voltage with resistors

Figure 3.28: The LM317 adjustable regulator

Figure 3.29: The LM317 as a constant current source

Figure 3.30: A PNP pass transistor increases output current

Figure 3.31: Q2 adds a current limit

Figure 3.32: Low drop regulator with auxiliary supply

For calculation of the ripple voltage and current for rectified and smoothed AC from a 50/60Hz transformer, check out this spreadsheet simulation