Crystal diode and transistor amplifier circuit 6

The above refers to the situation where only a fixed voltage is applied without an input AC signal. After adding the input signal, the voltage applied to the emitter junction is equal to the sum of the battery voltage Veb and the signal voltage. Since the signal voltage is constantly changing, the voltage on the emitter junction also varies with the signal voltage, causing a corresponding change in the height of the barrier layer of the emitter junction. When the potential barrier is high, the emitter current Ie is small, and when the potential barrier is low, diode Ie is large, which means that the emitter current Ie will change with the input voltage. If the emitter current Ie is large, it indicates that there are more holes reaching the base region, and more holes passing through the base region to reach the collector junction. diode As a result, the collector current Ic is also large. Conversely, if the emitter current Ie is small, the collector current will also be small. At the same time, we can also imagine that when the emitter current Ie is large

The number of complexes in the base area will also be more, and the number of complexes will correspondingly decrease when Ie is small, and the composite current will also vary. However, diode  this change, due to the already small composite current, is negligible compared to the changes in Ie or 1c. Here, we use Δ Ie to represent the change in emitter current and Δ Ic to represent the change in collector current.diode