How can I calculate R1 and R2 values for this transistor biasing circuit?

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SUMMARY

The discussion focuses on calculating the resistor values R1 and R2 for a transistor biasing circuit with a collector current (I0) of 10mA, an output voltage (V0) of 10V, and a supply voltage (Vs) of 16V. The DC current gain (hFE) is specified as 80. To determine R2, the voltage across it (6V) is used along with the total current (I0 + Ib), while R1 is calculated using the voltage across it (9.3V) and the base current (Ib).

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Hi guys,

I am trying to find a way to calculate biasing network for the attached circuit.

Basically I need to find R1 and R2 values for operating point of I0 = 10mA and V0 = 10V and Vs = 16V.
DC current gain is assumed to be hFE=80.

How do you calculate R1 and R2 based on these info? Please let me know.

Thanks in advance!
 

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You know the collector current Io so you can work out the base current from Hfe.

So, this total current (Io + Ib) passes through R2 and you know the voltage across R2 (16 - 10) so you can work out R2.

Then, you know the voltage across R1 (10 -0.7) and you know the current flowing in it (Ib) so you can work out the value of this resistor.
 

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