If you want to drive lowZ injectors without ballast resistors, you want to use PWMing. Since v3.2 the default autoassembled configuration comes with PWMing capability, so this is only needed for formerly ordered v3.1 or v3.0 (or if you let the smoke out of the FETdrivers somehow or you just want to donate 7 Euro :-).
PWMing on v3.0 .. v3.1 requires:
- 2*Rnet (5pin, 2k2..10k) to PWM the FETdriver inputs from the common signal
- 4*TC426 or TC4426 (SOIC8 package) 2 channel inverting FETdriver chip (compatible with MC34151D or MC33151D (each can drive 2 gates)
- 8*22..33 Ohm 0805 resistors (for FET gates)
Note that high-voltage (eg. 30V) flyback will smoke if PWMing is configured. So if you plan to configure PWMing, apply low voltage flyback ( because of injector cycle to cycle fluctuations, usually very hard to tune good idle below 2.0 msec injector pulsewidth),
see LowZ extension and
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