TITLE: 
                        
                            A Simple On-Chip Automatic Tuning Circuit for Continuous-Time Filter
                                
                                
                                    AUTHORS: 
                                            Chia-Hsiung KAO, Ping-Yu TSAI, I-Fan CHANG 
                                                    
                                                        KEYWORDS: 
                        Automatic, Tuning, Voltage-Controlled Filter (VCF), Single-Time Constant (STC) 
                                                    
                                                    
                                                        JOURNAL NAME: 
                        International Journal of Communications, Network and System Sciences,  
                        Vol.3 No.1, 
                        January
                                                        20,
                        2010
                                                    
                                                    
                                                        ABSTRACT: A simple on-chip automatic frequency tuning circuit is proposed. The tuning circuit is modified from voltage-controlled filter (VCF) frequency tuning circuit. We utilize an operational transconductance amplifier and a capacitor to from a single-time constant (STC) circuit which can produce a controllable delay time clock to tune the frequency of the filter. It can efficiently reduce the deviations in the 3 dB bandwidth from the variations of PVT (Process, Voltage and Temperature). The design of the STC circuit is simpler than VCF and it has less chip area. The chip has been implanted using TCMC 0.35 μm CMOS technology and the power consumption is less than 9.05 mW.