TP 4.6: A 900mV 40μW Switched Opamp DeltaSigma Modulator with 77dB Dynamic Range
نویسندگان
چکیده
Portable electronic systems require low-voltage low-power building blocks. An important building block is an A/D converter. ∆Σ ADCs provide an efficient way of trading off speed for resolution. The switched opamp (SO) technique allows design of switched-capacitor (SC) circuits at very low supply voltage without the use of multithreshold technologies or voltage multipliers to drive the switches [1]. The basic idea of it is to leave out the switches connected to the output of the amplifier in a SC integrator, because those are the ones that fail to conduct when the supply voltage is low. Switches can only be connected to well-chosen reference voltages. In this implementation the differential modified SO integrator cell is used, so the reference voltages are VSS and VDD [2]. This allows maximum overdrive of VDD-VSS for the switches.
منابع مشابه
A Third-Order Low-Distortion Delta-Sigma Modulator with Opamp Sharing and Relaxed Feedback Path Timing
This paper proposes a third-order low-distortion deltasigma modulator (DSM). The third-order noise shaping is achieved by a single opamp (excluding the quantizer). In the proposed DSM structure, the timing limitation on the quantizer and dynamic element matching (DEM) logic in a conventional low-distortion structure can be relaxed from a nonoverlapping interval to half of the clock period. A cy...
متن کاملA Low Power Audio Delta-Sigma Modulator with Opamp-Shared and Opamp-Switched Techniques
A high power efficient opamp-shared and opamp-switched delta-sigma modulator (DSM) has been presented. It employs a fourth-order single loop 17-level DSM with an input feed forward gain stage. It is shown that power consumption can be largely reduced by using half delay integrators and switched opamp, and sharing opamp between integrator stages. The proposed DSM, designed on 0.35μm TSMC process...
متن کاملAnalysis and Design of a Current Mirror Trans-conductance Switchable Op-amp for Switched-Capacitor Integrators
A switchable operational amplifier (op-amp) that uses a switched capacitor integrator has an advantage such as low power consumption and wide gain-bandwidth product. The power reduction is achieve by apply switching samples at the input and output capacitors. These capacitors can be otherwise would contribute in increase in power consumption. During the first phase of the sample the opamp compl...
متن کاملVery Low-Voltage Digital-Audio Modulator with 88-dB Dynamic Range Using Local Switch Bootstrapping
A 1-V 1-mW 14-bit modulator in a standard CMOS 0.35m technology is presented. Special attention has been given to device reliability and power consumption in a switched-capacitor implementation. A locally bootstrapped symmetrical switch that avoids gate dielectric overstress is used in order to allow rail-to-rail signal switching. The switch constant overdrive also enhances considerably circuit...
متن کاملA Voltage-Mode Switched-Capacitor Bandpass ∆Σ Modulator
A novel fourth-order voltage-mode switched-capacitor bandpass ∆Σ modulator, using direct-charge-transfer pseudo-N-path resonators, is described. This modulator is insensitive to component mismatches and finite opamp bandwidth, and is also less sensitive to finite opamp gain than previous bandpass ∆Σ data converters. It is therefore suitable for high-speed communications applications.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1998