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

[aim1nonly]

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 V_s = 16V.
DC current gain is assumed to be h_FE=80.

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

Thanks in advance!

 

[vk6kro]

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.