VDB analysisDesign errors of 5% or less are acceptable, because of resistor tolerances.
Find the base voltage: Assumption: Base current is so small that it has no effect on the voltage divider. 5% error  > base current is 20 times smaller than the divider current.
Checking the assumption:
_{} Even under the worst case condition the calculation is within the 5% limit, hence the assumption can be done. Summary of Process and Formulas
HO: What will change if the emitter resistor increases to 2KΩ? (unchanged voltage divider)
Solution:
VDB LoadLine and QPoint
Saturation point:
  > _{} Cutoff point:
Qpoint:
Now we plot these values and get the load line and the Qpoint:
The values V_{CC}, R_{C}, R_{1}, and R_{2} are controlling saturation current and cutoff voltage. To move the Qpoint is possible by varying the emitter resistance (R_{C}). Get the Qpoint in the Middle of the Load Line To set the Qpoint is a important preparation as you will see later on. Effect of R_{E}: R_{E} too large  > Qpoint moves into cutoff Q  point in the middle of the load line: Half the value of I_{C (sat)} and redesign R_{E} I_{C (sat)} = 2.47 mA ==> 1.23 mA _{} Look for the nearest standard value:

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