**Codice identificativo insegnamento**: 052427**Programma
sintetico**: **Introductory concepts and
background:**

The transistor as an amplifier, performance
figures: maximum voltage gain, fT, power amplification and Johnson’s limit.
MOSFET: quadratic I-V dependence, channel length modulation.
Transconductance and maximum gain. Subthreshold operation. Dependence on
bias point of transconductance and cut-off frequency. Stray capacitance.
Multifinger MOSFET’s. Technology platforms.**OTA's and
OP-AMP's:**

The differential stage with resististive
loads. Performance of current mirrors. Effects of current mirror on
differential and common mode gains. CMOS OTA’s. Two stages topology. Bias
and systematic offset. Device Matching. Pelgrom’s formula. Input voltage
offset. Cascoded mirrors. Impact on gain and CMRR. Frequency response. Pole
splitting and GBWP. Slew Rate. GBWP/SR ratio. Alternative compensation
strategies with buffers and nulling resistor. Single stage OTA’s.
Telescopic/folded cascode topologies. Nested Miller compensation. Transient
response and in-band doublet. Class AB OTA's. OP-AMPs and output
stages.**Complements on Noise:**

Variance and power
spectrum. Noise sources. Physical models of thermal noise and shot noise.
Noise sources in FET's, input equivalent noise sources. 1/f noise and
Tvidis formula. Input equivalent noise sources of OP-AMP’s.**Active
filters:**

Introduction to active filters. First order cells.
Canonical form for the pole pair. Q- factor of the pair. Filter
sensitivity. Second-order cells. The Sallen-Key cell, loop gain, sizing
options, impact on filter sensitivity. The Universal filter (KHN cell).
Tow-Thomas cell. Options for filter synthesis: cascade of active cells,
resonant ladder networks. Active inductors. Quality factor and noise.
Implementation of active inductors with amplifiers and transconductors.
Synthesis with integrators. Switched capacitor filters. SC-integrator.
Output spectrum of a switched capacitor stage. Stray insensitive switches.
Non-inverting integrator. Non-idealities of SC filters: finite gain, clock
feed-through.