This paper presents a novel leapfrog signal flow graph （SFG） implementation by fully differential Op amp integrators, which combines low sensitivity, high dynamic range with simple circuit configuration. The direct ...This paper presents a novel leapfrog signal flow graph （SFG） implementation by fully differential Op amp integrators, which combines low sensitivity, high dynamic range with simple circuit configuration. The direct SFG simulation and leapfrog SFG simulation can yield integrator-based structures likewise, but both of them will lead to higher circuit complexity, noise density and sensitivity. Three Butterworth 5-order high-pass filters with a pass band edge frequency of 1.778 kHz are designed based on different SFGs. From the example, the noise density of the sim- plest leapfrog configuration is approximately 0.4 nV/Hz~/2 lower than those of the other two in the stop band, and shows the best noise density in the pass band. The sensitivity densities of two types of leapfrog filters are approxi- mately equivalent, while that of the direct SFG simulation filter is much higher. However, the pass band response of the simplest configuration is not as good as those of the other two because of two parasitic zeros （at 708 kHz, -31.6 dB and 1.59 MHz, 20.55 dB） and a parasitic pole （at 4.57 MHz, 45.5 dB）.展开更多
This paper introduces a high-revolution,200kHz signal bandwidth EA modulator for low-IF GSM receivers that adopts a 2-1 cascaded single-bit structure to achieve high linearity and stability. Our design is realized in ...This paper introduces a high-revolution,200kHz signal bandwidth EA modulator for low-IF GSM receivers that adopts a 2-1 cascaded single-bit structure to achieve high linearity and stability. Our design is realized in a standard 0.18μm CMOS process with art active area of 0.5mm× 1.1mm.The EA modulator is driven by a single 19.2MHz clock signal and dissipates 5.88mW from 3V power supply. The experimental results show that,with an oversampling ratio of 48, the modulator achieves a 84.4dB dynamic range,73.8dB peak SNDR, and 80dB peak SNR in the signal bandwidth of 200kHz.展开更多
基金Supported by Youth Research Fund of Naval Aeronautical Engineering Institute
文摘This paper presents a novel leapfrog signal flow graph （SFG） implementation by fully differential Op amp integrators, which combines low sensitivity, high dynamic range with simple circuit configuration. The direct SFG simulation and leapfrog SFG simulation can yield integrator-based structures likewise, but both of them will lead to higher circuit complexity, noise density and sensitivity. Three Butterworth 5-order high-pass filters with a pass band edge frequency of 1.778 kHz are designed based on different SFGs. From the example, the noise density of the sim- plest leapfrog configuration is approximately 0.4 nV/Hz~/2 lower than those of the other two in the stop band, and shows the best noise density in the pass band. The sensitivity densities of two types of leapfrog filters are approxi- mately equivalent, while that of the direct SFG simulation filter is much higher. However, the pass band response of the simplest configuration is not as good as those of the other two because of two parasitic zeros （at 708 kHz, -31.6 dB and 1.59 MHz, 20.55 dB） and a parasitic pole （at 4.57 MHz, 45.5 dB）.
文摘This paper introduces a high-revolution,200kHz signal bandwidth EA modulator for low-IF GSM receivers that adopts a 2-1 cascaded single-bit structure to achieve high linearity and stability. Our design is realized in a standard 0.18μm CMOS process with art active area of 0.5mm× 1.1mm.The EA modulator is driven by a single 19.2MHz clock signal and dissipates 5.88mW from 3V power supply. The experimental results show that,with an oversampling ratio of 48, the modulator achieves a 84.4dB dynamic range,73.8dB peak SNDR, and 80dB peak SNR in the signal bandwidth of 200kHz.
