a)In linear or active mode : For a give base current the collector current is constant even though the Vce can vary.across its terminal.
b)In linear or active mode :If Vce is kept constant then collector current varies in propotion to base current

So we can configure BJT as a CV or CC ?

 

To a first order approximation, its a CC device when in the linear or active mode (not saturated).

 

Thanks

 

When the Vce Vs Ic is plotted for a given Ib
a)with Vcc varying we reach a point where Ic (Y axis)is constant even though Vce (X axis) increases as Vcc is increased .Whats the significance of this ?
Does this mean even though the Vce changes across its terminals for a given Ib ...the Ic will be constant !

 

When the Vce Vs Ic is plotted for a given Ib
a)with Vcc varying we reach a point where Ic (Y axis)is constant even though Vce (X axis) increases as Vcc is increased .Whats the significance of this ?
Does this mean even though the Vce changes across its terminals for a given Ib ...the Ic will be constant !

In most cases the characteristic curves are not flat but have a slight upward slope. This means the collector current is nearly constant for a fixed base current, up to the point of destruction. In most cases it is the external circuitry that limits the collector current to a value that will prevent destruction. Increasing the base current doesn't get you more collector current because the device is saturated.