What is the purpose of using a differential amplifier with active load?

What is the purpose of using a differential amplifier with active load?

The purpose of a differential amplifier with active load is to provide an increase in the voltage gain. The total gain of a differential amplifier with active load is the product of the voltage gains of the discrete stages.

How do we calculate output voltage of differential amplifier with active load?

I want to compute the value of VO. I would have guessed that VO = VCC – VEB. Asuming VCC = 5V and VEB = 0.6 V, that would render VO = 4.4 V, as in the left branch of the circuit.

What is active loaded amplifier?

In circuit design, an active load is a circuit component made up of active devices, such as transistors, intended to present a high small-signal impedance yet not requiring a large DC voltage drop, as would occur if a large resistor were used instead.

What is a BJT differential amplifier?

Differential Amplifier using Transistor. A differential amplifier is designed to give the difference between two input signals. The emitters of both T1 and T2 are connected to a common emitter resistor so that the two output terminals V1OUT and V2OUT gets affected by the two input signals I/P1 and I/P2.

What is the equation of load current for a differential amplifier with an active load?

What is the equation of load current for a differential amplifier with an active load? Clarification: The load current is given as product of difference between input & output voltage and transconductance. Therefore, the equation of load current is , IL = gm×vd.

What is the advantage of active load?

Question: What are advantages of having an active load rather than a resistive load in a transistor amplifier? Select all that are true. less sensitive to variations in transistor parameters higher differential-mode gain Ad lower power smaller area on an IC lower common-mode gain Ac.

What is active load and passive load?

ANSWER: A load which is completely resistive is an active load; all the power goes into the resistance and is dissipated in heat and the current is in phase with the voltage. A purely passive load is when either a capacitor or ideal inductor is connected to the load.

What is the working of differential amplifier?

In a differential amplifier, the voltage generated at the output is proportional to the difference of the two input signals. So, when the two applied inputs are equal i.e., there is no difference between the two input voltage the resulting output voltage will be 0.

How can we effectively improve CMRR of a differential amplifier?

Answer: CMRR is the ratio of differential voltage gain (Ad) to the common mode voltage gain (Ac), so we can improve the CMRR by either increasing differential voltage gain or by decreasing common mode voltage gain. To increase CMRR, emitter resistance RE should be increased.

How does a BJT differential AMP bias a circuit?

BJT differential amp with current mirror biasing In order to properly bias this circuit, it is necessary to include . Two things are accomplished by including in our circuit. One of them is that we can induce the current in , and thus, the current in .

Which is easier to analyze MOSFET or BJT?

BJT and MOSFET differential amplifiers with active loads Due to design processes and the nature of the devices involved, BJT circuits are “simpler” to analyze than their FET counterparts, whose circuits require a few extra steps when calculating performance parameters.

How are active loads used in a differential amplifier?

•Active loads are essentially transistor current sources used in place of the resistive loads in the diff-amp circuits to increase differential-mode gain. • BJTs {MOSFETs} in the active load circuit are biased at Q-point in forward-active {saturation} mode.

How is a current mirror used in a differential amplifier?

In order to implement a successful current mirror, one transistor (here, ) must have a current induced in it to mirror it to the differential amplifier’s current source (here, ). After adding this current mirror to our BJT differential amplifier, the resulting schematic is: Figure 3. BJT differential amp with current mirror biasing