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There's a balance where the voltage at the collector Vce has just the exact value needed to feed just enough base current to maintain the collector current what's needed to get the voltage at the collector to be dropped to Vce from value Vcc. It can be coarsely calculated with Vbe and transistor's Hfe (see NOTE1). Or it can be found by simulating or by making a test circuit.

That biasing solution has one advantage: It reduces the dependency on transistor's Hfe which vary easily -50...+100% between the individuals of the same type. Also the collector leakage current doesn't affect as much the operating point as it would do in case Rb was connected between Vcc and the base.

Rc between the collector and the base is essentially a negative feedback mechanism which as a side effect reduces the gain in multistage transistor amplifiers, but that also can be considered as an advantage: The non-linearity of the transistor causes less distortion in a class-A amplifier stage.

NOTE1: One must solve equation group

Ic = Hfe(Vce - 0,7V)/Rb

Vce = Vcc - Rc(1 + 1/Hfe)Ic

The first one says that Ic = Hfe * Ib

The second one says the voltage drop in Rc is the collector current plus the base current multiplied by Rc

There's a balance where the voltage at the collector Vce has just the exact value needed to feed just enough base current to maintain the collector current what's needed to get the voltage at the collector to be dropped to Vce from value Vcc. It can be coarsely calculated with Vbe and transistor's Hfe (see NOTE1). Or it can be found by simulating or by making a test circuit.

That biasing solution has one advantage: It reduces the dependency on transistor's Hfe which vary easily -50...+100% between the individuals of the same type. Also the collector leakage current doesn't affect as much the operating point as it would do in case Rb was connected between Vcc and the base.

Rb between the collector and the base essentially causes a negative feedback, which as a side effect reduces the gain in multistage transistor amplifiers. But also that can be considered as an advantage: The non-linearity of the transistor causes less distortion in a class-A amplifier stage.

NOTE1: To get the operating point (=idle state Ic and Vce) one must solve the next equation group

Ic = Hfe(Vce - 0,7V)/Rb

Vce = Vcc - Rc(1 + 1/Hfe)Ic

The first one says that Ic = Hfe * Ib

The second one says the voltage drop in Rc is the collector current plus the base current multiplied by Rc.

There's a balance where the voltage at the collector Vce has just the exact value needed to feed just enough base current to maintain the collector current what's needed to get the voltage at the collector to be dropped to Vce from value Vcc. It can be coarsely calculated with Vbe and transistor's Hfe (see NOTE1). Or it can be found by simulating or by making a test circuit.

That biasing solution has one advantage: It reduces the dependency on transistor's Hfe which vary easily -50...+100% between the individuals of the same type.

It's a negative feedback mechanism which also reduces the gain in multistage transistor amplifiers, but that also can be considered as an advantage: The non-linearity of the transistor causes less distortion in a class-A amplifier stage.

NOTE1: One must solve equation group

Ic = Hfe(Vce - 0,7V)/Rb

Vce = Vcc - Rc(1 + 1/Hfe)Ic

The first one says that Ic = Hfe * Ib

The second one says the voltage drop in Rc is the collector current plus the base current multiplied by Rc

There's a balance where the voltage at the collector Vce has just the exact value needed to feed just enough base current to maintain the collector current what's needed to get the voltage at the collector to be dropped to Vce from value Vcc. It can be coarsely calculated with Vbe and transistor's Hfe (see NOTE1). Or it can be found by simulating or by making a test circuit.

That biasing solution has one advantage: It reduces the dependency on transistor's Hfe which vary easily -50...+100% between the individuals of the same type. Also the collector leakage current doesn't affect as much the operating point as it would do in case Rb was connected between Vcc and the base.

Rc between the collector and the base is essentially a negative feedback mechanism which as a side effect reduces the gain in multistage transistor amplifiers, but that also can be considered as an advantage: The non-linearity of the transistor causes less distortion in a class-A amplifier stage.

NOTE1: One must solve equation group

Ic = Hfe(Vce - 0,7V)/Rb

Vce = Vcc - Rc(1 + 1/Hfe)Ic

The first one says that Ic = Hfe * Ib

The second one says the voltage drop in Rc is the collector current plus the base current multiplied by Rc

There's a balance where the voltage at the collector Vce has just the exact value needed to feed just enough base current to maintain the collector current what's needed to get the voltage at the collector to be dropped to Vce from value Vcc. It can be coarsely calculated with Vbe and transistor's Hfe. Or it can be found by simulating or by making a test circuit.

That biasing solution has one advantage: It reduces the dependency on transistor's Hfe which vary easily -50...+100% between the individuals of the same type.

It's a negative feedback mechanism which also reduces the gain in multistage transistor amplifiers, but that also can be considered as an advantage: The non-linearity of the transistor causes less distortion in a class-A amplifier stage.

There's a balance where the voltage at the collector Vce has just the exact value needed to feed just enough base current to maintain the collector current what's needed to get the voltage at the collector to be dropped to Vce from value Vcc. It can be coarsely calculated with Vbe and transistor's Hfe (see NOTE1). Or it can be found by simulating or by making a test circuit.

That biasing solution has one advantage: It reduces the dependency on transistor's Hfe which vary easily -50...+100% between the individuals of the same type.

It's a negative feedback mechanism which also reduces the gain in multistage transistor amplifiers, but that also can be considered as an advantage: The non-linearity of the transistor causes less distortion in a class-A amplifier stage.

NOTE1: One must solve equation group

Ic = Hfe(Vce - 0,7V)/Rb

Vce = Vcc - Rc(1 + 1/Hfe)Ic

The first one says that Ic = Hfe * Ib

The second one says the voltage drop in Rc is the collector current plus the base current multiplied by Rc