How to make a 12V induction cooker in an old hard drive case

An induction cooker comes in different sizes and runs on different voltages. It can even be powered from a rechargeable battery, and assembled on the basis of an out-of-date hard drive. After all, the base of the disk is polycarbonate and aluminum - materials that can withstand high temperatures and do not conduct electric current. And all the parts are inexpensive. Therefore, it will not take much time and will not be expensive.

Required Parts

• 2 transistors IRF3205 - http://alii.pub/66pgpe
• 2 resistors at 220 Ohm - http://alii.pub/5h6ouv
• 2 diodes 1N4007 - http://alii.pub/5m5na6
• Capacitor 2-6 uF - http://alii.pub/66ph12
• ferrite core 15-20 mm for inductance - http://alii.pub/66lwtq (or ready-made choke 220 µH - http://alii.pub/66lx1w)

Induction heater circuit

The simplest two-transistor circuit induction heats up. The sample, which will be described below, has a touch button with a transistor switch and a voltage stabilizer. For ease of repetition, the secondary switching circuit with the touch button is not indicated.

Making a 12V induction mini cooker

To do this, remove the top cover of the HDD and remove all its contents.The electronic board is also unscrewed.

On the remaining base, two holes are prepared into which running N-channel field-effect transistors IRF3205 are installed (you can take similar powerful field-effect transistors with high switching speed and low resistance). They are needed to use direct current instead of alternating current. Transistors are isolated from the base!

Next, a 90 mm fan is removed from the old video card, RAM cooler, or somewhere else. It is better to take it with a metal base and blades. It is attached to a wide hole in the substrate using screws, superglue or other means.

Ferrite pads are installed around it (you can find it on the radio market or be smart).

10 turns of rolled copper wire with a diameter of 6 mm are laid on them, used as a load for the trigger circuit and at the same time as a heater (it is soldered to the field drains).

2 inductive coils are attached around the transistors (30-32 turns of 0.8 mm wire on a ferrite or other dielectric core). Dielectric material is also laid under them.

One terminal of the coil is soldered to the drain of its transistor, and the second is connected to each other. Next, the sources of the field workers are connected by a jumper. Before this, for convenience, you can bend their shutters. A thermally stable capacitance of 2 to 6 μF (in this case 2.3 μF) is installed between the drains. Two 220 Ohm resistors connected in series are soldered between the gates. 1n4007 rectifier diodes are soldered from the gates to the drains of adjacent transistors (anode to the gate). Power is supplied to the central point between the inductive coils (“+”) and to the sources of the transistors (“-”).

A linear voltage regulator L7805CV (LM7805) is installed.Its input is connected to a jumper between two coils, ground - to the midpoint between two resistors. A MOS transistor (irfz44) is attached next to it, replacing the relay that powers the fan and generator circuit. On top of these elements, a push-button touch sensor on/off the circuit is soldered through a small capacitance.

Next, the electronic board is put in place on the back side of the substrate and the power input is soldered to the original HDD connector.

The case is closed and the product is ready for testing.

The tests carried out show that the plan actually works. If you have a pacemaker, do not stand close when the device is turned on!

Watch the video