The paper details on-chip inductor optimization for a reconfigurable continuous-time delta-sigma (Δ-Σ) modulator based radio-frequency analog-to-digital converter. Inductor optimisation enables the Δ-Σ modulator with Q enhanced LC tank circuits employing a single high Q-factor on-chip inductor and lesser quantizer levels thereby reducing the circuit complexity for excess loop delay, power dissi...

This paper presents a novel sigma-delta modulator architecture dedicated to very low-power applications wherein third-order noise shaping is achieved with very modest constraints on the analog part. The architecture is based on an enhanced MASH structure where the feedback of every loop is the sum of its output and of the output of the following loops. The analytical model of the architecture i...

This work develops an adaptive sigma–delta modulator that is based on adapting the quantizer step-size using estimates of the quantizer input rather than the modulator input. The adaptive modulator with a first-order noise shaping filter is shown to be bounded-input bounded-output stable. Moreover, an analytical expression for the signal-to-noise ratio is derived, and it is shown to be independ...

This paper presents the design of a monobit 6 order delta-sigma modulator in a GaAs 0.2 μm technology. The central frequency is 750 MHz and the sampling frequency is 3 GHz. The reached resolution is 10.5 bits over a 10 MHz bandwith. The modulator operates from ± 5 V power supplies and consumes 5.7 W. Each block of the modulator is presented at transistor level. Two drawbacks are pointed out: lo...

This paper presents a design and analysis of electromechanical sigma-delta modulator for MEMS gyroscope, which enables us to control the proof mass and to obtain an exact digital output without additional A/D conversion. The system structure and the circuit realization of the sigma-delta modulation are simpler than those of the analog sensing and feedback circuit. Based on the electrical sigma-...

Sigma-delta ADC, not only has adopted the technology of oversampling, but also utilized noise shaping which modulate the quantization noise in the baseband to the high frequency area. It increases the SNR in baseband and the effective quantization number of the converter. Because of the modulation technology, it makes sigma-delta ADC allowed to use one bit comparator, in addition Conventional N...

Sinusoidal signal can be used as stimulus to test static and dynamic parameters of ADC. A sigma-delta modulation based sinusoidal signal generator for ADC testing in SOC was introduced. The generator was built on the same chip with ADC. A numerical resonator generated a sinusoidal signal which was converted to a single bit stream by a sigma-delta modulator. Due to oversampling, the quantization...

One of the greatest unsolved problems in the theory of sigma delta modulation concerns the ability to analytically derive the stability, or boundedness, of a high order sigma delta modulator (SDM). In this work, we describe the existing literature and try to clarify the issues involved. We fully derive the stability of first order sigma delta modulators, and derive some important results for th...

This paper introduces a new architecture for sensor interface circuits using a delta-sigma modulator. The three-level force feedback allows the use of a digital compensator to stabilize the loop. A 3rd-order delta-sigma structure shapes the opamp noise and allows two-chip implementation with high loop gain at low frequencies.

This paper brief the use of very high precision Noise shaping sigma delta modulation techniques for high applications that require a signal-to-noise ratio and high resolution. A continuous-time delta-sigma A/D modulator with OSR of 40, signal bandwidth of 1.5625 MHz and clocked at 500MHz is implemented. This achieves 78 dB SNR and 12 bits of resolution.