Some basic problems about BJT

[refugee]

problems in bjt

Would any one tell me the TRUE or FALSE of these question,and why,I'm confused about it

Ⅰ.A BJT is biased at constant collector current of 1mA, as VCB goes up VBE will decrease.

Ⅱ.In a BJT Transistor, ICEO is β times ICBO.

Ⅲ.As Temp goes up, the beta(β)of goes up with TC of 5000 to 7000PPM.

Ⅳ.As the current density of a BJT goes up, its VBE will decrease.

Ⅴ.As the base sheet resistance of a BJT goes up, its emitter efficiency will decrease.

Ⅵ.The avalanche breakdown of a P+N Junction depends on the doping level of P+.

Your help will be appreciated.

 

[electronrancher]

I smell homework

 

[refugee]

No， It's just some exercises

 

[windgoal]

I. Ture, b/c of finite early voltage;
II. False, ICBO means "measure ICB when Emitter is open";
III. False, the curve of beta versus temperature is a bow bend.
iV. False, Ic=A*Js*exp(VBE/VT-1);
V. Ture
VI. False, depends on the ration of doping level on two sides.