Testing Procedure

Using a 12V source and a automotive 12v light bulb:

• connect up the bulb and record its current draw from the bulb and the voltage of the supply.

To measure the Voltage from Drain to Source

• connect negative to Source(S)
• connect voltmeter as shown
• connect the + side of the voltmeter to Drain (Bulb should be off)
• connect the + side of the voltmeter to Gate (will activate the mosfet)
• connect the + side of the voltmeter to Drain (Bulb should be ON)
• record voltage

Testing IRFP260 (Fake)

Measurements

Voltage: 12.09v

Current: 2.00A

Voltage Drain to Source: 0.42v

Calculated R(ds)

R(ds) = Vds / I = 0.42v / 2.00A = 0.210 ohms

Datasheet Specs

https://www.vishay.com/docs/91215/91215.pdf

R(ds) = 0.055 ohms

Result

FAKE!

Testing IRFP260 (Real)

Measurements

Voltage: 12.06v

Current: 2.00A

Voltage Drain to Source: 0.075v

Calculated R(ds)

R(ds) = Vds / I = 0.075v / 2.00A = 0.0375 ohms

Datasheet Specs

https://www.vishay.com/docs/91215/91215.pdf

R(ds) = 0.055 ohms

Result

Real!

References