3
\$\begingroup\$

What issues would one encounter by using a gate driver IC to directly drive a load instead of using it to drive transistors?

For consideration would be the very affordable Infineon 2EDN752x series dual low-side gate driver capable of 5A source and sink. The load would be inductive - a Wurth 732-2909-ND flyback transformer stepping the voltage up from 12v to about 140-180v. The transformer will be driven at a frequency range between 20kHz and 80kHz and a 25% duty cycle of 1s (250ms on 750ms off). Current draw will average less than 300mA.

What would be the issues of utilizing such a device as a full-bridge "in-and-of-itself" by connecting the outputs in series with the load and adding appropriate external protection such as flyback diodes?

This is specific to the Infineon 2EDN752x series of gate drivers, but it can just be considered as a starting point for this discussion. Click here for the datasheet.

The transformer is a Wurth Electronics 750845240 - Click here for the datasheet.

\$\endgroup\$
  • 1
    \$\begingroup\$ Gate drivers are meant for peaky current pulses, not continuous current and will overheat very quickly. That 5A rating is a peak rating due to its expected use. Their output resistance is on the order of 1 ohm. That's a lot of heat. \$\endgroup\$ – Toor Feb 28 at 15:34
  • 1
    \$\begingroup\$ 3125C temperature rise according to the thermal resistance listed. \$\endgroup\$ – Toor Feb 28 at 15:41
  • 1
    \$\begingroup\$ Welcome to SEEE, but please understand that this isn't a discussion forum. You ask specific questions and hope to get get specific answers. Questions like this one risk being closed as too broad or too opinion-based. \$\endgroup\$ – Finbarr Feb 28 at 15:45
  • \$\begingroup\$ @Finbarr I will modify the question to be specific to the datasheet provided. Thanks! \$\endgroup\$ – GabeNix Feb 28 at 15:47
  • 1
    \$\begingroup\$ @Toor - Very good point. A substantial current de-rating from the datasheet specification would need to figured into the potential circuit. This would limit possible uses. My consideration for this would be possible high speed switching applications with duty-cycles of less than 50%. And would place an average current draw of 300mA or less for this particular driver. \$\endgroup\$ – GabeNix Feb 28 at 15:53

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.