Question

Give the relation between Ie, Ic and Ib. Also give the order of their magnitude.

Answer 1

Explanation:

Ie =Ib+Ic where Ie is proportional to both Ib and Ic.

Thus, the value of Ib and Ic can never be individually greater than that of Ie.

Let Alpha (a) be the proportionality constant between Ie and Ic and

Beta (B) be the proportionality constant between Ib and Ic

Therefore,

For Active Region,

The collector junction is reversed biased (Jc) and the emitter junction (Je) is forward biased

Therefore

Ic = Ie × a and Ic = Ib × b

For Saturation region,

Both Jc and Je are forward biased

Therefore,

Ie(saturation) = aIe and Ic (saturation) =BIb.

For Cut off region,

Both Jc and Je are reversed biased

Therefore,

Ib = Ic = Ie = 0