D4Sparks - a ZVS driver for Flyback and other high voltage transformers.
In the examples below the supply is 12V DC and the primary winding is 3+3 turns (centre tapped) on the bare limb of the flyback.

D4Sparks is a great building block for tesla coils, Jacob's ladders an CO2 laser supplies.
When driving flyback transformers it will continue working even when the transformer's output is short circuit, making it suitable for capacitor charging.

Like all high voltage supplies the combination of a powerful FBT and D4Sparks driver could kill or inflict serious burns.
Only people experienced with high voltage electricity should build or operate this kind or equipment.

D4Sparks & a high power flyback transformer from a large back projection TV.


Video of these two bits used for a desktop Jacob's ladder. Jacobs_ladder.mpg 

You can charge capacitors - here a 1nF 15kV cap is charged until the gap between its feed wires breaks down.


The D4Sparks has a remote enable.  I got close to the transformer to take a video clip then enabled the D4sparks for 1 second.
It was a bit louder than I expected ;-)   d4sparks_cap.mpg

With the addition of some water cooling it can drive a small CO2 laser.


Video clip of  D4Sparks, FBT and a car windscreen washer pump being used to run a 10W CO2.
Shorting the two enable terminals turns the D4Sparks on.  D4SparksCO2.mpg

D4Sparks application info.

 Like all high voltage supplies the combination of a powerful FBT and D4Sparks driver could kill or inflict serious burns.
Only people experienced with high voltage electricity should build or operate this kind or equipment.
Knowledge of electronics, HV safety and a certain amount of test equipment is required.

The FBT contains an internal rectifier this means the output is pulsed DC.  When charging capacitors they will remain charged when power is removed.  The stray capacitance of the HV output can also shock after power is removed.  After operation it is essential that the output is discharged.  An earthed probe (connected to driver & FBT GND) with a well insulated handle is recommended.

Never touch the HV output or HV output cable during operation.
Electric shocks, Ozone, UV radiation from any discharge and fire due to discharge igniting flammable material are all anticipated hazards.

 The driver and FBT have been tested using a 3+3 turn primary wound on the bare limb of the FBT.  The supply was 12VDC.  The no load output is approximately 15kV.
Operating at other voltages is possible but the user is responsible for checking the rating of the MOSFETs and determining a suitable number of primary turns.







Schematic of FBT



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