Search results
Results From The WOW.Com Content Network
A silicon p–n junction in reverse bias. Connecting the p-type region to the negative terminal of the voltage supply and the n-type region to the positive terminal corresponds to reverse bias. If a diode is reverse-biased, the voltage at the cathode is comparatively higher than at the anode. Therefore, very little current flows until the diode ...
Nonideal p–n diode current-voltage characteristics. The ideal diode has zero resistance for the forward bias polarity, and infinite resistance (conducts zero current) for the reverse voltage polarity; if connected in an alternating current circuit, the semiconductor diode acts as an electrical rectifier.
In the discussion below, focus is on the NPN BJT. In what is called active mode, the base–emitter voltage and collector–base voltage are positive, forward biasing the emitter–base junction and reverse-biasing the collector–base junction. In this mode, electrons are injected from the forward biased n-type emitter region into the p-type ...
A PN junction in forward bias mode, the depletion width decreases. Both p and n junctions are doped at a 1e15/cm3 doping level, leading to built-in potential of ~0.59V. Observe the different Quasi Fermi levels for conduction band and valence band in n and p regions (red curves). A depletion region forms instantaneously across a p–n junction.
This band alignment is due to the biasing conditions that correspond with forward-active mode; forward bias on the emitter-base junction and reverse bias on the base-collector junction. Licensing I, the copyright holder of this work, hereby publish it under the following license:
A load line diagram, illustrating an operating point in the transistor's active region.. Biasing is the setting of the DC operating point of an electronic component. For bipolar junction transistors (BJTs), the operating point is defined as the steady-state DC collector-emitter voltage and the collector current with no input signal applied.
A graphical representation of the current and voltage properties of a transistor; the bias is selected so that the operating point permits maximum signal amplitude without distortion. In electronics, biasing is the setting of DC (direct current) operating conditions (current and voltage) of an electronic component that processes time-varying ...
Under zero- or reverse-bias (the "off" state), a PIN diode has a low capacitance. The low capacitance will not pass much of an RF signal. Under a forward bias of 1 mA (the "on" state), a typical PIN diode will have an RF resistance of about 1 ohm, making it a good conductor of RF. Consequently, the PIN diode makes a good RF switch.