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Voltage Gain VG in the Grounded Emitter Connection

Author: Leonard Krugman

The voltage gain was defined by equation (3-24) in terms of the general four-terminal parameters as:


The voltage gain in terms of the transistor parameters for the grounded emitter connection becomes:

transistor_basics_04-32.gif Eq. (4-9)*

The maximum voltage gain defined by equation 3-25 is:


which in this case becomes

transistor_basics_04-31.gif Eq. (4-9A)

For the point-contact transistor, assuming RL = 30,000 ohms and Rg = 10 ohms,


and the maximum voltage gain is transistor_basics_04-26.gif

For the junction transistor, with RL = 100,000 ohms and Rg = 10 ohms, the voltage gain is


and the maximum voltage gain is transistor_basics_04-28.gif

Notice that the voltage gain in this connection, like the current gain, is negative. Again this merely indicates that the input voltage is inverted in phase.

Last Update: 2010-11-17