analysis of two transistors ib,ic,ie? - Electrical Engineering Stack Exchange
your forgetting re.
you need use effective resistances r4 , r6, value
\$r4_e = r4 * (1+\beta) = 40,000 * 101 = 4,040,000\omega\$ \$r6_e = r6 * (1+\beta) = 1,000 * 101 = 101,000\omega\$
using base circuit looks this.
simulate circuit – schematic created using circuitlab
you solve using various methods, shortcut realise that, ideal vbe, voltage @ top of both emitter resistors identical. such can treat both legs being in parallel. circuit can further simplified to..
now should able calculate current through circuit as..
\$i_{rb} = (2.6 - 0.6)/(2,260 + 98,540) = 19.84ua\$
that makes base voltages both..
\$v_b = 2.6 - 19.84ua * 2.26k\omega = 2.555v\$
so
\$ib1 = (2.555-0.6)/4.04m\omega = 0.484ua\$.. , \$ib2 = (2.555-0.6)/101k\omega = 19.356ua\$
however: these numbers make sense if transistor not saturated. question states \$i_e \approx \beta * i_b\$ indicates in case not.
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