What is Q point in load line?

Also, the Q Point is the relationship between the diode forward voltage and current defined by the device characteristic. Consequently, there is only one point on the dc load line where the diode voltage and current are compatible with the circuit conditions.

How do you find the Q point from a load line?

Every transistor circuit has a load line. If the base resistance is given you can also calculate the current and voltage for the operating point. By plotting IC (2.9 mA) and VCE (6.3V), we get the operation point —-> Q-point (quiescent point).

How do you find the Q point of a transistor?

How do you find the Q point or operating point of a transistor?

If the transistor is used as a switch then for open switch the Q-point is in the cutoff region, and for the close switch, the Q-point is in the saturation region. The Q-point lies in the middle of the line for the transistor which operates as an amplifier.

How is the Q-point chosen for a transistor?

There can be many such intersecting points, but the Q-point is selected in such a way that irrespective of AC signal swing, the transistor remains in active region. This can be better understood through the figure below. The load line has to be drawn in order to obtain the Q-point.

How to calculate the load line of a transistor?

To obtain the load line, the two end points of the straight line are to be determined. Let those two points be A and B. When collector emitter voltage V CE = 0, the collector current is maximum and is equal to V CC/R C. This gives the maximum value of V CE.

How is the Q-point of a load line fixed?

By solving the established level of IB, the actual Q-point could be fixed as shown in Fig 4.12 If we vary the magnitude of IB by varying the RB value, we find the Q-point shifts towards upward or downward across the load line as depicted in Fig. 4.13.

Which is the operating point of a load line?

When a line is drawn joining these two points, such a line can be called as Load line. This is called so as it symbolizes the output at the load. This line, when drawn over the output characteristic curve, makes contact at a point called as Operating point. This operating point is also called as quiescent point or simply Q-point.