Is BJT is current controlled device?

Is BJT is current controlled device?

A BJT is a current controlled device because its output characteristics are determined by the input current.

Are transistors current controlled?

Full Member level 3. A bipolar transistor is said to be current controlled because when it is biased in the active region the output (collector) current is controlled from the input (base) current.

Are BJT transistors still used?

Yes, BJTs are still used. BJTs have higher transconductance, which gives them higher gain. They are ideal for amplifiers, where you want to maximize the gain. There is actually considerable amount of research going on in how to replicate the BJT performance in CMOS technology, especially for satellite applications.

How BJT is current controlled?

BJT is current controlled due to the relationship between input (base current) and output (collector current). Ic = BETA*Ib. Where BETA is relatively constant over several decades of current. The MOSFET controls the channel charge based on the gate bias voltage (relative to source & bulk).

Does transistor control voltage or current?

Basically, a bipolar transistor amplifies a small current entering the base to produce a large collector current. It is a current-driven device since the collector current is controlled via the base current. The current gain varies with the collector-emitter voltage (VCE).

Why is a transistor classified as a current operated device?

In a transistor, emitter current= base current+collector current. It means emitter current controls the collector current and base current. For a given emitter current, collector current is controlled by base current. That is why, the transistor is a current operating device.

Why transistor is called as current controlled device?

Why transistor is called current controlled device? The output voltage, current or power is controlled by the input current in a transistor. So it is called the current controlled device.

Is a BJT current controlled or voltage controlled?

The confusion about whether a BJT is current controlled or voltage controlled comes from two sources. The first is that the equations we use in describing electric circuits are not definitions of one variable in terms of several others. Rather they are describing a constraint between several variables.

How does a BJT amplifier produce voltage?

If a voltage comes out of a BJT based amplifier that voltage is either the BJT’s collector current which is turned into a voltage by a resistor connected to the BJT’s collector orthe BJT is used as a voltage buffer (common collector or emitter follower) where it does not provide any voltage amplification but is does provide current amplification.

Is junction transistor a current or voltage controlled device?

Any VOLTAGE signal used the junction transistor base circuit must be converted (or limited) to a current of suitable size using a resistor or other device. Hence the junction transistor is a current controlled device that can be made to operate with an input voltage and external circuit components.

What is the difference between BJT and common emitter current gain?

Both explanations (a BJT is voltage controlled / current controlled) are valid models, each appropriate in a different context. So called “common emitter current gain” is a range not a constant. Good designs don’t depend on it.