VNQ9080AJ Flyback diodes for inductive loads

[emachabeeinnotag]

Hi,

I'm designing a custom PCB and I'll be using a VNQ9080AJ to drive 4 inductive loads (hydraulic valve spools).

Is the protection diode in the datasheet sufficient for that application?

The device will drive up to 28 VDC ~3.5 to 5 amps inductive loads.

I need to know if I need to add external flyback diodes.

Thanks!

[robert3]

For your application, the internal diode shown in the VNQ9080AJ datasheet can handle small inductive spikes, but for 4 inductive loads at 3.5–5 A each, it’s recommended to add external fast flyback diodes across each load.

Use diodes rated for at least the load current and reverse voltage (e.g., Schottky or fast recovery diodes) to ensure reliable operation and protect the IC from high-voltage transients.

The datasheet note about the ground diode/resistor (≈4.7 kΩ) helps with multiple HSDs sharing the same ground, but external diodes per load provide safer, long-term protection.