How to use a High power mosfet.

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1

Dear friends.

On last month I tried to drive a high power mosfet with a 12V signal (maybe change it to 24v in the future).
So, I found some boards and redid (reverse engineering) the schematic.

I will use this circuit to power (heater bands) to heat a container with liquid.

The heater have 200W @ 12V (maybe 24V in future)
Mosfet: HA210N06 (datasheet http://www.cecb2b.com/batchupload/inventoryother/zfa_ic_inventory/201495/zfa__332199_f13c9a0a038c37904c57614f101672ad.PDF)
Transistor: BC817-40 SMD (datasheet https://www.diodes.com/assets/Datasheets/ds11107.pdf)

With a lot of effort I came to the schematic, but my doubts are:
1 - The mosfet could "burn" and the circuit stay on? (it's not safe)
2 - Why this schematic use the BC817?
3 - Is this schematic correct?

thank you

mosfet-HA210n06.png
mosfet-HA210n06.png882×502 4.94 KB

2
  1. I can't definitively answer this, but every device that I've let the smoke out failed "open".
  2. You don't need the opto-isolator, you could probably drive the BC817 from the GPIO pin (through a suitable base resistor).
  3. Can't tell- you haven't said anything about the heater pads specifications.