| OTA-C filter is a frontier topic in the field of CMOS Integrated circuit design,it is widely used in the field of automatic control,communication engineering and electronic information.As one of the continuous-time filter,the OTA-C filter has a strong high-frequency characteristics and electrical control capability,it is compatible with MOS Technology. It is carried on the design of OTA at the first part of the Article, the OTA has Folded Cascode, it is reflected that the characteristics of a high gain and a low power consumption. On the basis of the OTA design.it is put forward a high resistance of full compensation OTA-C filter which has the part of switched capacitor and feedBack,it is used MOSFET instead of resistance, in order to achieve the high resistance of full compensation and low pass filter function.In this paper, UMC 0.18μm process, the Simulation results of Folded Cascode is that:the Voltage gain 89.53 dB, the unity gain bandwidth 128.63 MHz,the Slew Rate2.3V/us, the input voltage range 0.66 V ~ 1.98 V, the output voltage range 0V ~2.24 V, the common mode rejection ratio 62.43 dB, the power supply rejection ratio70.36 dB, the Power 5.565 mW, the layout area 0.32mm2.The actual simulation of two order low pass OTA-C filter is that : the cut-off frequency 1MHz, the pass-band ripple is less than 1dB, the require of minimum stop band attenuation rate1 dB, the stop-band attenuation is less than 50 dB.The design achieved the requirements. |
