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The only terminal remaining is the source. This is a common-source FET circuit. The analogous bipolar junction transistor circuit may be viewed as a transconductance amplifier or as a voltage amplifier. (See classification of amplifiers). As a transconductance amplifier, the input voltage is seen as modulating the current going to the load.
The common collector amplifier's low output impedance allows a source with a large output impedance to drive a small load impedance without changing its voltage. Thus this circuit finds applications as a voltage buffer. In other words, the circuit has current gain (which depends largely on the h FE of the transistor) instead of voltage gain. A ...
In most amplifiers a reduction in gain takes place before hard clipping occurs; the result is a compression effect, which (if the amplifier is an audio amplifier) sounds much less unpleasant to the ear. For these amplifiers, the 1 dB compression point is defined as the input power (or output power) where the gain is 1 dB less than the small ...
The output is usually connected to an external pull-up resistor, which pulls the output voltage to the resistor's supply voltage when the transistor is off. For PNP open collector outputs, the emitter of the PNP transistor is internally connected to the positive voltage rail , so the collector outputs a high voltage when the transistor is on or ...
A Class B push–pull output driver using a pair of complementary PNP and NPN bipolar junction transistors configured as emitter followers. A push–pull amplifier is a type of electronic circuit that uses a pair of active devices that alternately supply current to, or absorb current from, a connected load. This kind of amplifier can enhance ...
Transistor testers have the necessary controls and switches for making the proper voltage, current and signal settings. A meter with a calibrated "good" and "bad" scale is on the front. In addition, these transistor testers are designed to check the solid-state diodes. There are also testers for checking high transistor and rectifiers.
Figure 3: A shunt-series feedback amplifier. Figure 3 shows a two-transistor amplifier with a feedback resistor R f. The aim is to analyze this circuit to find three items: the gain, the output impedance looking into the amplifier from the load, and the input impedance looking into the amplifier from the source.
Three types of OTAs are single-input single-output, differential-input single-output, and differential-input differential-output (a.k.a. fully differential), [1] however this article focuses on differential-input single-output. There may be an additional input for a current to control the amplifier's transconductance.