5. Base-emitter saturation voltage VBE(sat)： Fig. 8
First, apply a voltage of about 0.6 V between the base and emitter with the voltage source VBE. After that, the collector current IC is applied while gradually increasing until the specified current is reached. Next, adjust VBE so that the base current IB is the default, and measure the voltage between the base and emitter at this time. This voltage is VBE(sat).
If the current source on the collector side is applied while the transistor is off, it may become an abnormally high voltage and destroy the transistor. Set the voltage when the current source is open so that it is less than the collector-emitter voltage VCEO described in the absolute maximum ratings.
VBE(sat) is temperature dependent (Fig. 9).
This characteristic VBE(sat) is a spec that makes a pair with collector-emitter saturation voltage (Table. 2).
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