What is a CMOS differential amplifier?
A differential amplifier is a circuit whose output voltage is directly proportional to the difference between voltages applied at it’s to inputs. A typical CMOS differential amplifier circuit is shown below. Fig.1 — CMOS Differential Amplifier Circuit. All MOSFETs are in saturation.
Which of the transistor is used for designing CMOS differential amplifier?
The circuit consists of NMOS and PMOS devices, where n-channel MOSFET is used to form differential pair and p-channel current mirror load is used. The technology used, is 0.18µm and 1.8V supply voltage is applied. The design and simulation has been carried out in ADS tool.
What is differential amplifier in VLSI?
A differential amplifier is a type of electronic amplifier that amplifies the difference between two input voltages but suppresses any voltage common to the two inputs.
What is a differential amplifier used for?
Differential amplifiers are used mainly to suppress noise. Noise consists of typical differential noise and common-mode noise, of which the latter can easily be suppressed with an op-amp.
What does a differential amplifier do?
How are the MOSFETs in a CMOS differential amplifier?
A typical CMOS differential amplifier circuit is shown below. All MOSFETs are in saturation. Also, we ca n see from the circuit that MOSFETs 3 and 4 act as a current mirror, hence are of the equal dimensions. That’s the case with MOSFETs 5 and 6.
How to find the gain of a differential amplifier?
For a fully symmetric differential pair which senses inputs by equal and opposite amounts then the concept of half circuit can be applied to find the gain of the differential amplifier. For the circuit shown in below Figure, by using the concept of half circuit, the small signal gain is given as,
How does a differential amplifier solve common mode DC level?
The variation of the transconductance in turns leads to change in the small signal gain of the amplifier. In order to solve the problem of common mode dc level the circuit shown in above figure is modified by employing a current source I SS to make (I D1 + I D2) independent of V in, cm .
What does CMRR stand for in differential amplifier?
CMRR is a measure of how well the differential amplifier rejects the common-mode input voltage in favor of the differential-input voltage. Input common-mode range (ICMR) The input common-mode range is the range of common-mode voltages over which the differential amplifier continues to sense and amplify the difference signal with the same gain.