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What is cascode amplifier find its gain?
The C-B stage provides a high voltage gain, AV = -181. Current gain of cascode is β of the C-E stage, 1 for the C-B, β overall. Thus, the cascode has moderately high input impedance of the C-E, good gain, and good bandwidth of the C-B.
What is current mirror used for?
The current mirror is used to provide bias currents and active loads to circuits. It can also be used to model a more realistic current source (since ideal current sources don’t exist).
What is cascode circuit?
The cascode is a two-stage amplifier that consists of a common-emitter stage feeding into a common-base stage. In modern circuits, the cascode is often constructed from two transistors (BJTs or FETs), with one operating as a common emitter or common source and the other as a common base or common gate.
What are the features of a cascode amplifier?
A cascode amplifier consists of a common-emitter stage loaded by the emitter of a common-base stage. A cascode amplifier has a high gain, moderately high input impedance, a high output impedance, and a high bandwidth.
What kind of transistors are used for cascode?
The cascode circuit can also be built using bipolar transistors, or MOSFETs, or even one FET (or MOSFET) and one BJT. This circuit arrangement was very common in VHF television tuners when they employed vacuum tubes . The cascode arrangement offers high gain, high bandwidth, high slew rate, high stability, and high input impedance.
Where did the BJT cascode amplifier come from?
Before the invention of the RF dual gate MOSFET, the BJT cascode amplifier could have been found in UHF (ultra high frequency) TV tuners. A cascode amplifier consists of a common-emitter stage loaded by the emitter of a common-base stage.
Which is better a cascode circuit or a triode circuit?
However, the screen in a pentode partitions the current through the tube and this makes the pentode generally noisier than a triode. The cascode circuit can achieve the same high gain as the pentode and enjoys the same reduction of Miller Effect.