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Four quadrants MOSFET graph

1. Four quadrants MOSFET graph

Low loss ideal diode circuits use MOSFETs in opposite direction to create the ideal diode. Here we must know that, in contrast to bipolar transistors, MOSFETs conduct in two directions. Nevertheless it is weird that only one quadrant is shown at the manufacturers MOSFET characteristic curves. I haven’t found four quadrants MOSFET graphs, so I have done measurements and created such a chart myself. Note that in the reverse direction the body diode is active.

Here is a 4 quadrants graph of an IRFP140 MOSFET. The range is limited, it is only for showing the behaviour in the reverse direction.

4 quadrants N channel enhancement MOSFET output characteristic curves

Here is a 1 quadrant MOSFET graph from the manufacturer.

1 quadrant MOSFET output characteristic curves

2. Ideal diode circuit example

There are many components available to create ideal diodes. To find applications Google “ideal diodes ic”.

LTC4352 ideal diode controller circuit