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Currently, I'm designing Zeta Converter for my projects and I made this design. enter image description here

When there is no supply applied to the zeta converter, the PWM signal seems good. enter image description here

But it ends up getting a bad turn-off signal like this picture when the supply applied enter image description here

edited: so each channel are connected to PWM1/PWM2 & SOURCE to see how PWM signals are. PWM1/PWM2 are connected to the GATE of MOSFETS and SOURCE are connected to the SOURCE of MOSFETS

connector power to ic

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    \$\begingroup\$ Please show layout, and preferably a photo of where the probes are connected and oriented. \$\endgroup\$ Aug 3, 2023 at 14:00
  • \$\begingroup\$ sorry, I just edited the post. please take a look \$\endgroup\$
    – tabun
    Aug 3, 2023 at 14:10
  • \$\begingroup\$ A schematic of the gate driver circuit would be very interesting. \$\endgroup\$
    – Jens
    Aug 3, 2023 at 14:12
  • \$\begingroup\$ For the gate driver circuit, you can see it in the schematic I posted. At the top right of the picture \$\endgroup\$
    – tabun
    Aug 3, 2023 at 14:14
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    \$\begingroup\$ Apparently the ground of scope (or scope's GND lead) is disturbed. Is there any physical connection between the scope's ground and IN– of the circuit? Try isolating the GND of the scope (from it's power cord) and re-take the measurements. \$\endgroup\$ Aug 3, 2023 at 15:09

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If the circuit is made on a solderless breadboard then the capacitance and inductance of the rows of contacts and the wires all over the place make oscillation like you show.

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  • \$\begingroup\$ I'm not using a solderless breadboard. The first experiment was using perforated PCB and it work. Then I printed it into a PCB. \$\endgroup\$
    – tabun
    Aug 3, 2023 at 14:40

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