Question

Find the output resistance for a NPN BJT transistor at VBₑ​=0.7. The early voltage is 40 V. The saturation current is 10⁻¹⁴ A. At VBₑ​=0.7 V, Find the collector current at VCₑ​=2 V and 8 V.

Answer 1

The output resistance for a NPN BJT transistor can be calculated using Ro = VA / IC, where Ro is the output resistance, VA is the Early voltage, and IC is the collector current. The collector current at VCₑ=2 V and VCₑ=8 V can be found using IC = IS * (e^(VCₑ/VT) - 1), where IS is the saturation current and VT is the thermal voltage.

Step-by-step explanation:

To find the output resistance for a NPN BJT transistor at VBₑ=0.7 V, we need to use the equation for the output resistance of a BJT transistor:

Ro = VA / IC

where Ro is the output resistance, VA is the Early voltage, and IC is the collector current.

Given that VBₑ=0.7 V, we can calculate the collector current at VCₑ=2 V and VCₑ=8 V using the equation:

IC = IS * (e^(VCₑ/VT) - 1)

where IS is the saturation current and VT is the thermal voltage.

Let's calculate the collector current at VCₑ=2 V and VCₑ=8 V using the given values:

IC(2V) = 10⁻¹⁴ A * (e^(2/0.026) - 1)

IC(8V) = 10⁻¹⁴ A * (e^(8/0.026) - 1)