Heat resistor

Hello,
I would like to control a heating resistor of 12v, 200W with my arduino UNO R3 board. Does anyone know of a module to do this?
I hope to have given enough information, if not warn me.

You would need a MOSFET, that supports 20Amps. E.G. IRLZ34NPBF

missdrew:
You would need a MOSFET, that supports 20Amps. E.G. IRLZ34NPBF

At 46miiliohm. That's 13W dissipation (large heatsink) and a voltage drop of 0.75V
(which means only 175W get to the heater).

Something more like 5 milliohm or so would be a better choice as the heatsink
could be much more managable. (Choosing MOSFETs by max current is not the
best way - the on-resistance is more revealing)

Far easier to find a non-logic level MOSFET, power it from the 12V and drive it
with a level shifting circuit or MOSFET gate driver chip.

Alternatively you could mount the MOSFET on the thing you are trying to heat alongside the
resistor?

For such a device you would want to drive the gate at nearly 10 Volts to get the low resistance quoted on the data sheet.

You didn’t mention how you want to control the heater. ON/OFF or control heat by some sort of PWM.

If PWM you could decide to switch the MosFet on and off at the standard Arduino PWM frequency. I don’t think that is a good idea. Each time you switch the MosFet on or off you create extra loss in the MosFet. If you could switch the load on and off at maybe 10 Second rate or longer. It will depend on how quickly your heater and load react.

You can cheat a bit and use a BTS7960 H bridge module, they can be gotten for well under $8.00 including shipping. They will do the 200 Watts without a problem. I use them for Dual LED drivers all the time. I use them for high side because the P fet has a lower RDSon. As far as PWM frequency, MOSFETs can be driven in the Mhz range with the proper drive. While it takes virtually no continuous current to turn on or off the MOSFET, it does take considerable pulse current to charge and discharge the gate quickly. Hundreds of milliamps or more are often needed for very fast switching. MOSFETs themselves can switch very quickly. Gate resistors defeat this pulse current requirement. Another part is the BTS660, it will conduct 10 amps generally without a heatsink and be cool. Please note these devices have a minimum voltage which 12V exceeds so they will be good.

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