Parasitic Integrators: Balancing the Act Parasitic integrators are a fascinating and powerful technique in CMOS analog IC design. They offer a way to achieve...
Parasitic integrators are a fascinating and powerful technique in CMOS analog IC design. They offer a way to achieve precise and robust integration without requiring explicit feedback circuitry.
This approach comes with unique advantages and disadvantages:
Advantages:
Perfect match: Integrators achieve perfect match between the desired and the actual function, eliminating the error caused by parasitic capacitance.
High accuracy: By eliminating parasitic effects, they achieve high accuracy and resolution in the final integrated circuit.
Robustness: Their structure is simple and cost-effective, making them ideal for specific applications where resource constraints are important.
Disadvantages:
Complexity: Implementing parasitic integrators adds complexity to the circuit design.
Matching conditions: Achieving perfect match requires precise matching of both the parasitic and the desired capacitors, which can be challenging to achieve.
Limited applications: Their use in specific designs may be restricted due to their complexity or the need for precise matching.
Examples:
Voltage-controlled resistors: These integrate voltage changes using parasitic capacitance. By varying the voltage, the resistance changes, achieving a controllable resistance value.
Controlled capacitors: These integrate the difference between two voltages, effectively filtering noise while maintaining high accuracy.
High-pass filters: Integrating with parasitic capacitors allows designing filters with sharper roll-off and improved stability.
Parasitic integrators represent a powerful tool for achieving precise and robust analog circuits. While their complexity presents a challenge, their advantages outweigh this drawback, making them valuable for specific applications where accuracy and simplicity are crucial