Komal
Last Activity: 9 Years ago
The "Early Effect" is a modulation of the base collector depletion region. For a transistor under normal bias, the base collector region is in reverse bias. As the collector emitter voltage grows, the reverse bias increases, slowly increasing the size of the depletion region, but enabling more charge carriers to make it across the depletion region and get swept up by the base emitter forward biased diode.
If you look at the IV characteristic of a transistor, you would hope Ic would be constant with Vce. However, you will notice the current grows ever so slightly. Some transistors are better than other transistors.