Modeling and Design of a Novel Architecture of Sigma-Delta Converter for Sensor Measurement

This paper presents a novel architecture of high-order single-stage sigma-delta (ΣΔ) converter for sensor measurement. The two-step quantization technique was utilized to design of novel architecture of ΣΔ modulator. The time steps are interleaved to achieve resolution improvement without decreasing of conversion speed. This technique can be useful for low oversampling ratio. The novel architecture was designed to obtain high dynamic range of input signal, high signal-to-noise ratio and high reliability. This paper describes steps involved in a new VHDL design of a decimation filter for a ΣΔ modulator. Parameters of decimation filter are derived from the specifications of the overall ΣΔ modulator. The proposed architecture of switched-capacitor (SC) ΣΔ modulator was simulated with nonidealities blocks, such as sampling jitter, noise, and operational amplifier parameters (white noise, finite dc gain, finite bandwidth, slew rate and saturation voltages).