The designing of op-amps puts new challenges in
low power applications with reduced channel length
devices. Advancements which have appeared recently
through new techniques and technologies, give us
multiple alternatives in implementations. Involvement
of Design Automation (DA) tools in analog and mixed
signal design is still not matured as it is in the digital
design domain. Accommodation of short channel
effects in DA for mixed-signal design is also
challenging task for EDA designers.
Here for high gain and high bandwidth applications
the well known and enough matured fully differential
topology has been employed. For biasing purpose we
have designed a current mirror circuit which utilizes a
single current source and makes this design free from
biasing voltage sources. Post layout simulation result
shows that the DC differential gain of 95.278 dB,
135.34 MHz unity gain frequency, 52.8o phase margin,
and 131.74 V/uS slew rate are some of the quantitative
figure of op-amp designed here. Section 2 briefs about
art of op-amp design whereas section 3 explains the
analysis of each building block of a two stage op-amp.
Design principles behind the design are in section 4.
Section 5 talks about the circuit analysis and
implementation. Simulation results are presented in
section 6 and finally section 7 concludes the work with
future directions and improvements.