The emitter is heavily doped, while the collector is lightly doped, allowing a large reverse bias voltage to be applied before the collector base junction breaks down.
42.
The DC bias voltage supplies the FET amplifier ( at a low current ), while the capacitor decouples the DC supply from the AC input to the recorder.
43.
These microphones evolved from the carbon microphones used in the early days of aviation and the telephone which relied on a DC bias voltage across the carbon microphone element.
44.
For example, a bias voltage is applied to a transistor in an electronic amplifier to allow the transistor to operate in a particular region of its transconductance curve.
45.
Phantom power is sometimes used by workers in avionics to describe the DC bias voltage used to power aviation microphones, which use a lower voltage than professional audio microphones.
46.
Another application of reverse biasing is Varicap diodes, where the width of the depletion zone ( controlled with the reverse bias voltage ) changes the capacitance of the diode.
47.
Q3 is a common emitter stage that provides amplification of the signal and the DC bias current through D1 and D2 to generate a bias voltage for the output devices.
48.
Thus the device is turned off not by reverse bias voltage applied to the gate, as in the case of conventional MOSFET but by full depletion of the channel.
49.
They are often used in pairs to switch between two different RF sources such as the VHF and UHF bands in a television tuner by supplying them with complementary bias voltages.
50.
X-ray photons create electron-hole pairs in a-Se, and the transit of these electrons and holes depends on the potential of the bias voltage charge.
