Fast Locking Time Biquadratic Band-Pass Filter Utilizing Nonlinear Sliding-Mode Controller

Abstract

This paper considers design procedure of fast locking time self-tuning [Formula: see text] biquadratic band-pass filter with nonlinear sliding mode control. A sliding mode controller is building block of the phase control loop (PCL) involved to push central frequency to reach input signal frequency very fast, approximately 100–200[Formula: see text]ns. The sliding mode controller is realized by using a tunable delay line, enabling optimal filter locking time for different input signal frequencies. The filter possesses low sensitivity to component discrepancy and is applied as a selective amplifier. The 0.13[Formula: see text][Formula: see text]m SiGe BiCMOS technology has been utilized for design and verification of the presented filter. This filter has central frequency up to 220[Formula: see text]MHz, quality factor [Formula: see text] and 25[Formula: see text]dB gain.

A High-Accuracy RC Time Constant Auto-Tuning Scheme for Integrated Continuous-Time Filters

“…However, in complementary metal-oxide semiconductor (CMOS) technologies, the absolute value of resistance and capacitance is greatly affected by process and temperature. As a result, RC time constant uncertainty of up to 50% could occur due to variations in process, voltage, and temperature (PVT); this uncertainty will reduce the frequency performance of filters, leading to reliability issues in integrated circuits [ 5 , 6 , 7 , 8 , 9 , 10 ]. Accordingly, many real-time on-chip automatic tuning methods have been proposed and developed to improve the accuracy in the calibration of the RC time constant [ 2 , 6 , 11 , 12 , 13 , 14 , 15 ].…”

“…As a result, RC time constant uncertainty of up to 50% could occur due to variations in process, voltage, and temperature (PVT); this uncertainty will reduce the frequency performance of filters, leading to reliability issues in integrated circuits [ 5 , 6 , 7 , 8 , 9 , 10 ]. Accordingly, many real-time on-chip automatic tuning methods have been proposed and developed to improve the accuracy in the calibration of the RC time constant [ 2 , 6 , 11 , 12 , 13 , 14 , 15 ]. However, most existing methods are limited by some disadvantages.…”

“…Since both circuits suffer from the same PVT variations, the RC time constant of the slave circuit can be tuned [ 15 , 19 , 26 , 27 , 28 ]. The change in capacitance does not influence the operating points of transistors; thus, the linearity of the system is not affected [ 6 , 15 , 29 ]. Unfortunately, the master–slave tuning scheme usually suffers from nonidealities in real applications.…”