Is this description correct for the three working conditions of a transistor? To achieve these conditions, how should the peripheral circuit...

QWE4562009

Is this description correct for the three working conditions of a transistor? To achieve these conditions, how should the peripheral circuit... [Copy link]

Is this description of the three working conditions of a transistor correct? To achieve these conditions, how should the peripheral circuit be calculated? Let's take the NPN transistor as an example!

1nnocent

The description in red is correct, but the peripheral circuit still needs to be combined with the specific circuit.

For example, if we use the common emitter amplifier circuit for analysis, we divide the voltage of Rb1 and Rb2 to set Vb, and calculate Ib and Ic, VCC-Ic*Rc=Vc.

Now that Vb and Vc are calculated, we can set the three states as described in red, and make the Rb2 partial pressure less than Ve.

If you know how to calculate the working point, it is not difficult to set these three working states

QWE4562009

1nnocent posted on 2021-6-19 16:02 The description in red is correct. For the peripheral circuit, it still needs to be combined with the specific circuit. For example, if the common emitter amplifier circuit is used for analysis, the Rb1Rb2 voltage divider setting...

Hello, is VE equal to VBE? 0.6V? For silicon tubes

QWE4562009

1nnocent posted on 2021-6-19 16:02 The description in red is correct. For the peripheral circuit, it still needs to be combined with the specific circuit. For example, if the common emitter amplifier circuit is used for analysis, the Rb1Rb2 voltage divider setting...

I don’t know IC and IB yet. How do I calculate VC?

1nnocent

QWE4562009 posted on 2021-6-19 16:34 Hello, is VE the same as VBE? 0.6V? For silicon tubes

Yes

1nnocent

QWE4562009 posted on 2021-6-19 16:35 I don’t know IC and IB yet. How to calculate VC?

First you need to measure the β value of the transistor, Ib can be calculated, the above figure Ib = (Vb-Vbe) / Re / (1 + β)

Ic=βIb, I omitted it because I thought you could calculate it. IRb1 must be more than ten times greater than Ib.

QWE4562009

1nnocent posted on 2021-6-19 17:22 QWE4562009 posted on 2021-6-19 16:35 I don’t know IC and IB yet. How to calculate VC? First you need to measure the transistor’s & ...

Hello, thanks for your guidance. Generally speaking, you need to know the six parameters of VC, IC, VB, IB, VE, RC, and RB. Of course, the parameter tables of β and VBE are already known.

QWE4562009

1nnocent posted on 2021-6-19 17:22 QWE4562009 posted on 2021-6-19 16:35 I don’t know IC and IB yet. How to calculate VC? First you need to measure the transistor’s & ...

There are more experts in this forum...

1nnocent

1nnocent posted on 2021-6-19 17:22 QWE4562009 posted on 2021-6-19 16:35 I don’t know IC and IB yet. How to calculate VC? First you need to measure the transistor’s & ...

It depends on the need. It is good to know how to calculate. Personally, I think the parameters of triode are nothing more than Ib, Ic, Vb, Vc, Ve.

QWE4562009

1nnocent posted on 2021-6-19 18:31 It depends on the need. It is good to know how to calculate. Personally, I think the parameters of triode are nothing more than Ib, Ic, Vb, Vc, Ve.

Hello, for example, if you want to enter amplification or saturation, what calculation steps are needed? For example, which parameter should be calculated first, and which one should be calculated later?