Producing negative to positive square wave pulse

Question

Situation

I need 2 kHz -10/40 V square wave duty <1 % pulse to drive 50 ohm load.
I have a working 0-40 V solution: PWM by MCU driving a N-MOSFET low side switch off a 40 V DC rail.

schematic

^{simulate this circuit – Schematic created using CircuitLab}

Questions:

Is it possible to somewhat shift the voltage to negative after MOSFET output (low side is tricky, no common ground)?
If not, what is the most practical way to produce such pulse?

If you need low to be -10 volts irrespective of changes in duty cycle then you need a negative rail or circa 12 volts. Create one or make one or redefine 0 volts as -10 volts. — Andy aka, Commented Feb 3, 2021 at 15:16
If you don't have a -10 V supply, you can use a zener clamp with a DC restorer starting with a 50V supply. using very low ESR RdsOn parts tinyurl.com/y2rvywy6 — D.A.S., Commented Feb 3, 2021 at 23:25
@Andyaka Could you please show me how to use the negative rail ? If I insert negative rail to high side, L will be short. If I insert negative to low side, MCU will be burnt. — 7E10FC9A, Commented Feb 6, 2021 at 11:51

The Force Awakens · Accepted Answer · 2021-02-06 12:05:39Z

-1

The best way to do this is by using a differentiator(op-amp circuit).This website provides the basics.

answered Feb 6, 2021 at 12:05

The Force Awakens

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