resistors' value in transistor circuit

[smiles]

Suppose you know the type of transistor, this transistor's circuit also include many resistors around it, what parameter of transistor (get from datasheet) that you need to know for the enough calculating (finding the value of resistors) ?
Thanks !!!
Here is its datasheet https://pdf1.alldatasheet.com/datasheet-pdf/view/21668/STMICROELECTRONICS/2N1613.html

 

[hbaocr]

hello,smiles
U need attension to hefe (DC gain cuurent) to design your circuit to terminate resistor value. Note Ic max (collector current max) to design a limited current.
example .For designing transistor as switch which Ic =100 mA. You calculate Rc to limit Ic curent. after chosing Rc(Resistor on collector) => Ib(current on base)= Ic/(hfe*k) .(K= safety factor , usually chosing k=4). and base on Ib you can terminate Rb(resistor on base).

 

[smiles]

As you say, and get from datasheet, I have these parameters
Ic Collector Current 500 mA (ok, this is Icmax value)
hFE* DC Current Gain for 2N1613
................Ic = 500 mA......Vce = 10 V........hFE(typical) = 55
Do I need Vce for calculation ?

 

[hbaocr]

hi, smile . Transistor usually use as two function in three region operation of it.

When it i used as swicth, It work in two region : ( saturated region , and break down region).when it is saturated Vce≈ 0, and Ic =VCC/( Rc+Re ) while (Ic ≥hfe*Ib).on this case you must note Ic on datasheet to note that it must be more than Ic which u need to design
when it in break region it is considered no current through Collector and Vce ≈ Vcc ( U need to notice Vce on datasheet must be more than Vcc in order to avoid destroying C -E junction)
Ic =500ma on datasheet is the max current that CE junction can tolarate. Simliar to Vce that is the max voltage drop on CE junction. When U design , you can also choose Ic < Ic max =500ma , and Vce <Vce max

when it is working on linear region. it works as amplifying signal device . The signal on Base will amplify with gain =hfe on Colletor
According to your Bias . You Transistor can either Work in two above function
note that hfe can change when temperature change.
Ic , Vce on datasheet are the max factor which transistor can tolerate
cheer

 

[smiles]

Thanks so much !!!