I built the little circuit shown in the schematic below. As you can see, I took a lot of measurements, some of which I understand and some I don't.
The circuit is powered with a 6V lantern battery. The base bias for Q1 comes from another circuit which is also powered from the lantern battery, but only supplies 3.33V as an output signal. When I attach it to R4, the voltage drops to 1.75 and then there is a .93V drop across R4, so the final bias voltage for Q1 is .81V. The base current is .935mA (less than 1 mA,) and the collector current is 55mA, so β for Q1 in this circuit is 58.8.
I understand that R1-R3 limit the collector current to 55mA, but what I would like to know is whether Q1 is in saturation, and if so, is it considered "soft" or "hard" saturation.
My other hope is that someone will show me the math for Ohm's law as it applies to biasing Q1. (Yeah, I am a little embarrassed to ask.)
Thanks in advance.
The circuit is powered with a 6V lantern battery. The base bias for Q1 comes from another circuit which is also powered from the lantern battery, but only supplies 3.33V as an output signal. When I attach it to R4, the voltage drops to 1.75 and then there is a .93V drop across R4, so the final bias voltage for Q1 is .81V. The base current is .935mA (less than 1 mA,) and the collector current is 55mA, so β for Q1 in this circuit is 58.8.
I understand that R1-R3 limit the collector current to 55mA, but what I would like to know is whether Q1 is in saturation, and if so, is it considered "soft" or "hard" saturation.
My other hope is that someone will show me the math for Ohm's law as it applies to biasing Q1. (Yeah, I am a little embarrassed to ask.)
Thanks in advance.
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