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 BLOG     PIC Tutorials     Time for Science     24 February
2009 Author: Giorgos Lazaridis BJT Transistor theory  Transistor
Circuit Essentials Choosing the right bias  After selecting the
proper connection, the one that is most suitable for your
application, you must select a biasing method. Biasing in
general means to establish predetermined voltages and currents
at specific points of a circuit, so that the circuit components
will operate normally. For transistors, biasing means to set the
proper voltage and current of the transistor base, thus setting
the operating point, also known as quiescence point (Q). We will
discuss in details the quiescence point within the next
chapters. For now, you need to know that this point will
determine how the transistor will operate (amplifier or switch).
A correctly placed Q offers maximum amplification without signal
distortion or clipping.  The most efficient and commonly used
biasing method for transisto