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

How do we calculate output voltage of a 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 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 differential pair in VLSI?

The differential pair is all about balance. Thus, for optimal performance the resistors and MOSFETs must be matched. This means that the channel dimensions of both FETs must be the same and that R1 must equal R2. The resistance value chosen for the two resistors will be referred to as RD (for drain resistance).

What is active load in 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 differential gain can be improved using active load?

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. Diff-pair induces a change in IC {ID}, which in turn, produces a change in VEC {VSD}. → Refer to Figure 11.27 for BJT.

What is differential pair circuit?

Differential pair PCB routing is a design technique employed to create a balanced transmission system able to carry differential (equal and opposite) signals across a printed circuit board. That each of the two signal lines is properly terminated in its own characteristic impedance at the receiver end.

What is an active load circuit?

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 happens when diff pair is split in active load?

Don’t forget, though, that the diff pair converts the output from differential to single-ended without loss of gain —in other words, the factor-of-two reduction that occurs when we split the drain-resistor diff pair does not apply to the active-load configuration.

How are differential pairs used in amplifier design?

Differential pairs are used as the input stages of operational amplifiers and operational transconductance amplifiers, common mode feedback circuits, and analog multipliers. As with the other fundamental building blocks, a good understanding of differential pairs is required for successful analog circuit design.

What is the reference current of the MOSFET differential pair?

Also, if we assume perfect matching, the bias current will be divided equally between the two halves of the circuit (as with the drain-resistor-based differential pair). This means that the reference current is I BIAS /2.

What is the bottom half of the differential pair?

The bottom half of the differential pair is the same as what we would expect from the drain-resistor version. But now, instead of drain resistors, we have a PMOS current mirror.