Design automation of ΔΣ switched capacitor modulators using spice and MATLAB

Abstract

Concerning the fact that the design of contemporary integrated circuits (IC) is practically impossible without using sophisticated Electronic Design Automation (EDA) software, this paper gives some interesting thoughts and considerations about that issue. As technology processes advances on year basis consequently EDA industry is forced to follow this trend as well. This, on the other hand, requires IC designer to frequently and efficiently accommodate to new working environments. Authors of this paper suggest a method for high level circuit analysis that is based on using common (open source or low cost) circuit simulators but precise and fast enough to meet requirements imposed by demanding mixed-signal blocks. The paper demonstrates the proposed EDA procedure on an example of second order ?? modulator design. It illustrates considerable simulation time saving which is more than welcome in a world of analogue and mixed-signal design. [Projekat Ministarstva nauke Republike Srbije, br. TR32004: Advanced technologies for measurement, control, and communication on the electric grid]

Low power duty cycle adjustment simple method in high speed serial links

“…Adjustment circuit contains digital feedback with switch capacitors [5] . In this structure analog blocks are Low Pass Filters (LPF), DC corrector and analog mux.…”

Operational Transconductance Amplifier in 350nm CMOS technology

“…Being part of SC circuits the OA requires relatively high slew-rate and gain-bandwidth. As shown in [4], open loop i.e. DC gain has the smallest influence, comparing to slew-rate and gain bandwidth, on SC circuit characteristics.…”

“…Since on-chip capacitors are considered, 2pF differential load capacitance is adopted. This value is also set by higher order circuit requirements concerning kT/C noise of ΔΣ structure explained in [4]. It should be mentioned that target technology process offers Poly-insulator-Poly (PiP) capacitors with 864 aF/μm 2 capacitance per unit area.…”