The design considerations for fast-settling operational
amplifiers (opamps) differ significantly between sampled-data switchedcapacitor
(SC) and conventional continuous-time applications. In SC
circuits, the shape of the output voltage waveform of an opamp is of no
consequence provided that the output settles to within a specified
tolerance of its steady-state value prior...
Pulse Width Modulation (PWM) has been used extensively for motor control, DC-AC
converters, DC-DC converters and in audio applications. The conventional method of
generating a pulse width modulated signal involves generating an accurate sawtooth or triangle
wave using analog circuits. In CMOS, being analog circuit intensive puts extra constraints
on...
The design and implementation of Switched-Current (SI) ladder filters is
described. SI filters require only a standard digital CMOS process and the power
supply voltage requirement is low. SI circuits also can be potentially operated at
higher frequencies than Switched-Capacitor (SC) filters due to the low-impedance
wideband nodes of the...
In recent years, there has been an extensive effort to develop low-cost implementations
of radio frequency integrated circuits for consumer applications. This thesis is a
research effort in the design and implementation of integrated RF CMOS Power Amplifiers
(PAs). A significant challenge in the implementation of RF CMOS ICs is...
The chopper-stabilized operational amplifier has good low
frequency noise properties. Unfortunately a simple technique for
simulation of the chopper-stabilized operational amplifier has
not been available.
This thesis describes the implementation of a differential
amplifier using chopper stabilization and its circuit modeling
for the SPICE simulation. This circuit has been designed...
Full integration of CMOS low noise amplifiers (LNA) presents a challenge for low
cost CMOS receiver systems. A critical problem faced in the design of an RF CMOS LNA
is the inaccurate high-frequency noise model of the MOSFET implemented in circuit
simulators such as SPICE. Silicon-based monolithic inductors are another...
Nowadays, wireless communication systems use high-order quadrature amplitude modulation (QAM) together with orthogonal frequency-division multiplexing (OFDM) to increase the link capacity and robustness. These signals always have large peak-to-average power ratio (PAPR) and require power amplifiers (PAs) achieve both high efficiency and linearity simultaneously. For the efficiency, the complementary metal...
The sensors in real time data processing IoT devices require high resolution and sub-MHz data converters, usually implemented as Incremental ADCs due to the advantages of oversampling technique and low latency. In discrete time incremental (IDT) ADCs, the sampling switch non-linearity, charge injection degrade the resolution, and power hungry OPAMPs...
Multi-level decision feedback equalization (MDFE) is an effective technique to remove inter-symbol interference (ISI) from disk readback signals, which uses the simple architecture of decision feedback equalization. Parallelism which doubles the symbol rate can be realized by setting the first tap of the feedback filter to zero.
A mixed-signal implementation...
Sensor system plays an important role in connecting everything including human body to the electrical information systems that we have built and that we are going to build, to make the world more intelligent and efficient. One of the key propulsive forces behind these emerging techniques is CMOS scaling that...