I am designing a 2N2222 transistor common emitter voltage-divider amplifier. Using 9V for the power supply and trying to make the loadline to determine Q. How do I determine the sauration point current for the load line?voltage-divider amp

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    \$\begingroup\$ Please include a schematic so we know what you mean when you say "voltage-divider amlifier". \$\endgroup\$ – The Photon May 3 '19 at 18:38
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    \$\begingroup\$ What do you mean by "saturation point current"? Do you mean the collector current at which the transistor starts to go into saturation? You do realize that for most practical purposes, the amplifier will be horribly distorting at amplitudes much lower than the point where the thing goes into saturation, yes? \$\endgroup\$ – TimWescott May 3 '19 at 18:55
  • \$\begingroup\$ The goal is for the amp to oscillate between saturation and cutoff without clipping. How do I determine the saturation current from the datasheet for 9V? \$\endgroup\$ – SamR May 3 '19 at 19:19
  • \$\begingroup\$ without a small Re will result in very high gain but very distorted for full swing due to Vbe square law. If you want to learn how to design, learn what specs matter 1st, and include say for max swing bias point, with Zin= input impedance and low-frequency cutoff (RC values) and THD or as I prefer, it is easiest to measure AC coupled % asymmetry error for distortion.by difference in +,- in peaks / total swing.... ANY questions? \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 May 3 '19 at 20:31
  • \$\begingroup\$ Yes, just one. What is the Ic saturation point and where is it found on the datasheet? \$\endgroup\$ – SamR May 3 '19 at 20:47

try this circuit


simulate this circuit – Schematic created using CircuitLab

the saturation current will be 9v/2,000 = 4.5ma

If BETA is 100, this circuit will automatically (negative DC feedback) make the collector voltage be near VDD/2, no matter what is the VDD.

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    \$\begingroup\$ Is R1 supposed to be 200k(ish) instead of 2k? \$\endgroup\$ – The Photon May 4 '19 at 15:09

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