Sensivity Comparisons for Third Order Integrated Circuit Filters

1
Sensivity Comparisons for Third Order Integrated
Circuit Filters

• Luis A. González Abel González Segarra
• Advisors
• Dr. Rogelio Palomera (RUM) Dr. Manuel Jiménez
  (RUM)
• Kishore Ganti (IBM)

2
Overview

• Filters Introduction
• Applications
• Synthesis Methods for IC
• Design Goals
• Simulation Data

3
What is a Filter?

• Frequency selective device
• Analog or Digital
• Passive
• Active
• Low-pass, High-pass, Band-pass

4
Ideal Characteristics
H(j?)
H(j?)
passband
stopband
passband
stopband
?
?
?c
?c
H(j?)
passband
stopband
stopband
?
?1
?2
5
Synthesis Methods for Integrated Circuits

• RC active with Operational Amplifiers
• LC simulation System
• Leap Frog Methods
• Impedance Simulation
• Continuous Time Filters
• Switched Capacitor Circuits

6
LC Chebyshev Approximation for Third Order
Lowpass, Highpass, and Bandpass
7
Inductorless Active Filters

• Amplifiers, capacitors, resistors and/or switches
• Filter approximation
• Required for integrated circuits
• Third order filters

8
Sensitivity and Tolerance

• Sensitivity function the ratio fractional change
  of a network function
• Tolerance affects sensitivity of circuits.

9
Importance of Sensitivity Study

• Tolerances of components
• Quality factor, gain, cutoff frequencies
• Circuits responses
• Making selections

10
Third Order Sallen-Key LP Quality Factor vs. DC
Gain (1)
11
Third Order Sallen-Key LP Quality Factor vs. DC
Gain (2)
Setting C1 C2 C and R1 R2 R5R
where
12
Future Work

• Redesign of lossless ladders implementing
  Gyrators with transistor equivalents
• Make sensitivity comparisons between common
  filter approximations for new and previous
  designs