# Split supply common-emitter design

Please assist me with this design problem

Design and construct a single stage common-emitter amplifier with the following characteristics:  The voltage gain should be at least 100V/V;  The input resistance should be at least 5 kΩ;  The output resistance should not exceed 2,2 kΩ;  The circuit must be operated from a +10V /0/-10V (split supply). (Hint: consider the split-emitter also called the partially bypassed configuration)

Does the voltage divider biasing formulas apply to this configuration? Where do I actually begin?

Hints: -

Start with what is told and draw a circuit that is compatible with the question. Next, I would take the output resistance of 2.2k as an indicator what the collector resistance needs to be. Go look that up because these are hints and I'm not doing your homework. Given the gain of the required circuit and knowing the collector load resistor, the emitter resistance is directly calculatable.

You might also find along the way that the emitter resistance is in fact a resistor in parallel with a series capacitor and resistor i.e. three components. Go look up what that is all about because you won't learn without finding some stuff out.

Finally the base needs to be biased with a potential divider.

What your question doesn't contain is what frequency range you need to oeprate at and whether the amplifier blocks dc. These are things I cannot answer and are needed to do the job properly.

Here is a good tutorial on a common-emitter amplifier circuit that can help with your design. It also includes info on the split-emitter concept.

http://www.electronics-tutorials.ws/amplifier/emitter-resistance.html