I am trying to use a transistor for the fist time. I have spent hours reading various post on forms which has led to more confusion than answers. If someone please point me into the right direction
I have attached my circuit I am working on. I am trying to solve the resistance for R3
The formula I have found form this site R=(VVbe)/Ib
If I am understanding every thing (12.9)/.005=2220. My R3 resistor should be 2,2K ohm @ 5% or 1.26K ohm @ 1%?
Data sheet for D3, Kingbrit WP710A10SRCE http://www.kingbrightusa.com/images/catalog/SPEC/WP710A10SRCE.pdf
Forward voltage 1.8 Typ, If 20 mA with maximums of 30 mA and 75 mW
Using a 560 ¼ w ohm resistor I should get a load of 17.7 mA with 34 mW
Data sheet for Q1 , Fairchild BC548 https://media.digikey.com/pdf/Data Sheets/ON Semiconductor PDFs/BC54650.pdf
Typ. Vbe (sat) 900 Typ with the conditions of Ic 100 mA , Ib 5 mA
I have attached my circuit I am working on. I am trying to solve the resistance for R3
The formula I have found form this site R=(VVbe)/Ib
If I am understanding every thing (12.9)/.005=2220. My R3 resistor should be 2,2K ohm @ 5% or 1.26K ohm @ 1%?
Data sheet for D3, Kingbrit WP710A10SRCE http://www.kingbrightusa.com/images/catalog/SPEC/WP710A10SRCE.pdf
Forward voltage 1.8 Typ, If 20 mA with maximums of 30 mA and 75 mW
Using a 560 ¼ w ohm resistor I should get a load of 17.7 mA with 34 mW
Data sheet for Q1 , Fairchild BC548 https://media.digikey.com/pdf/Data Sheets/ON Semiconductor PDFs/BC54650.pdf
Typ. Vbe (sat) 900 Typ with the conditions of Ic 100 mA , Ib 5 mA
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