Voltage Inverter Switches Research Articles

Three Phase Three-Level PWM Switched Voltage Source Inverter With Zero Neutral Point Potential

A new three phase three-level pulsewidth modulation (PWM) switched voltage source inverter with zero neutral point potential is proposed. It consists of three single-phase inverter modules and each module is composed of a switched voltage source and inverter switches. The major advantage is that the peak value of the phase output voltage is twice as high as that of the conventional neutral-point-clamped PWM inverter. Thus, the proposed inverter is suitable for applications with low voltage sources such as batteries, fuel cells, or solar cells. Furthermore, three-level waveforms of the proposed inverter can be achieved without the switch voltage unbalance problem. Since the average neutral point potential of the proposed inverter is zero, a common ground between the input stage and the output stage is possible. Therefore, it can be applied to a transformerless power conditioning system. The proposed inverter is verified by a PSpice simulation and experimental results based on a laboratory prototype

Novel analog-digital converters using voltage inverter switches. II. applications

For pt.I see ibid., vol.38, no.6, p.582-589 (1991). The use of voltage inverter switches (VIS) in analog-to-digital converter (ADC) circuits is described. In the first part of this paper VIS circuits were introduced, and their use in voltage reference circuits was demonstrated. In this second part, these reference circuits are incorporated into novel ADC circuits. Six different circuits are presented and analyzed; the principles on which these are based are the two-capacitor array, the algorithmic principle, the incremental principle, and the delta-sigma principle. The simulation of these circuits shows that the use of the VIS reference circuits leads to improved performance over current circuits. The circuits are based on CMOS technology and are wholly realizable on silicon. >

Novel analog to digital converters using voltage inverter switches. I. Reference circuits

Novel analog to digital converter (ADC) circuits that incorporate voltage inverter switches (VISs) are described. In the first part the principles of voltage inversion are described. It is shown how these circuits can be used to construct very accurate divide-by-two reference circuits. Due to the ability of the VIS circuits to compensate for parasitic losses during the process of capacitor charge redistribution, these reference circuits are superior to previous designs. Three different VIS reference circuits are presented. Theoretical analyses are confirmed with computer simulations and measured results from experimental circuits.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Transfer functions for switched-capacitor and wave digital filters

Closed-form expressions are presented for amplitude-oriented low-pass, high-pass, and bandpass sampled-data transfer functions suitable for realization as 1) switched-capacitor lossless discrete integrator (LDI) ladder filters, or 2) wave digital filters. Other types of realizations are also possible, such as those employing voltage inverter switches (VIS's), the recently introduced switched-capacitor "voltage wave" filters, and standard recursive digital realizations. The filters possess optimum equirippie (or maximally flat) passbands and monotonic stopbands with arbitrary selectivity. The low-pass and high-pass cases are derived from distributed passive prototype functions, but the more important bandpass functions are quite novel, appearing here for the first time.

Integrated 18th-order pseudo-N-path filter in VIS-SC technique

An integrated 18th-order frequency symmetrical switched-capacitor (SC) bandpass filter is described that was realized by the use of voltage inverter switches (VISs) in the form of recharging devices. The filter was implemented in a standard CMOS technology. It was conceived for use as a `channel filter' in modulation schemes for PCM/FDM and audio/FDM conversion. Starting from a high-pass filter as reference filter, the SC filter is designed as a pseudo-N-path filter, with N=2. The application of the pseudo-N-path principle leads to a substantial saving in hardware.

Integrated 18th-order pseudo-N-path filter in VIS-SC technique

An integrated 18th-order frequency symmetrical switchedcapacitor (SC) band-pass is described that has been realized according to the approach involving the use of voltage inverter switches (VIS's) in form of recharging devices. The has been implemented in a standard CMOS technology. It has been conceived for use as channel filter in modulation schemes for PCM/FDM and audio/FDM conversion. Starting from a high-pass as reference filter, the SC is designed as pseudo- N -path filter, with N = 2 . The application of the pseudo- N -path principle has lead to a substantial amount of saving in hardware.

Novel voltage inverter switches with minimum sensitivity properties

A class of switched-capacitor (SC) filters using voltage inverter switches (VIS's) with minimum sensitivity properties is proposed. The novel realizations use only fully stray-eliminating (usually referred to as stray-insensitive) SC circuits and offer a true one-to-one correspondence between the elements of the reference filters and the network capacitors of the corresponding SC circuits. Thus the transfer functions of the proposed SC filters depend only on the matching properties of the network capacitors if the open-loop gain of the required operational amplifiers is sufficiently high. In this way the excellent sensitivity and noise Performance of the underlying passive prototypes are retained.

A note on some early work in the field of switched-capacitor networks

In this paper, some early work in the field of switched-capacitor (SC) filters, which has been done in Europe since about 1960, will be discussed. In particular, reasons will be explained as to why the early (and some later) approaches in Europe went into quite a different direction than the switched-capacitor (SC) filter design started in the United States in 1977. In contrast to these later approaches, which were dominated by the idea of substituting switched capacitors instead of resistances, mostly in order to realize unidirectional signal-flow graph filters, the early European concepts concentrated on the simulation of pure reactances by means of capacitances and special switches, which could achieve lossless charge transfer in order to simulate doubly terminated reactance filters. Modern descendants of this type of filters are the switched-capacitor (SC) filters using voltage inverter switches. Since these filters are operated bidirectionally, very useful equivalences to time-invariant circuits and network theorems concerning stability and passivity can be derived. In the following, an outline of the fundamental ideas that have led to such equivalences will be presented.

New realization of inductances for switched-capacitor filters using voltage inverter switches

This paper describes a new design method of inductance simulation for switched-capacitor (SC) filters based on the VIS-SC concept. The resulting circuits have not only the excellent sensitivity behavior of VIS-SC filters, but also the low sensitivity to the main parasitics occuring in the MOS integrated circuit, i.e., the parasitic capacitances between the bottom plates of the implemented capacitors and substrate. As examples, a sixth-order band-pass and a sixth-order band-stop elliptic filter transformed from a third-order low-pass are given. Experimental results agree very well with theory. A brief analysis is given of certain parasitic effects in band-stop filters at the Nyquist frequency.

Scaling techniques for switched‐capacitor filters employing voltage inverter switches

AbstractSome realizations of scaling elements in cascade connection with unit elements and gyro‐elements will be described. It will be shown that the voltage distribution inside the filter and the spread of capacitor values can be optimized in two steps using two independent parameters for each scaling element. the influence of these scaling elements is such that the very low sensitivity of the attenuation characteristic with respect to element variations is fully retained despite the fact that according to the usual definition the losslessness of the reference filter is not preserved. the SC circuits described in this paper are insensitive to ‘bottom plate’ parasitic capacitances. Top plate parasitics correspond largely to element variations in the reference filter so that also their influence is strongly reduced. A numerical example of a 14th‐order unit element bandpass filter is given.

MOS switched-capacitor filters using voltage inverter switches

Low-sensitivity switched-capacitor filters imitating <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</tex> and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</tex> /unit-element structures can be built by means of capacitances, ordinary switches, and voltage inverter switches, the latter being quite simply realizable by electronic means (either with or even without operational amplifier). There are no restrictions on the operating rate (other than those resulting from the Nyquist theorem) nor on the location of the attenuation poles. Experimental results of an integrated third-order lowpass filter are in good agreement with theory. The effects of parasitic capacitances can be overcome by using proper design techniques.

Erratum: Cascade synthesis of switched-capacitor networks employing voltage inverter switches

The switched-capacitor equivalents of gyrators and transformers in cascade with unit elements are presented. This, together with the basic elements proposed by Fettweis, can be used to simulate various analogue sections which are used in cascade synthesis.

Cascade synthesis of switched-capacitor networks employing voltage inverter switches

The switched-capacitor equivalents of gyrators and transformers in cascade with unit elements are presented. This, together with the basic elements proposed by Fettweis, can be used to simulate various analogue sections which are used in cascade synthesis.

MOS switched-capacitor filters with reduced number of operational amplifiers

Using voltage inverter switches, exact analog sampled-data equivalents of Rs, Ls and Cs, as well as unit elements, can be designed with MOS capacitors and switches. Due to the underlying bilinear transformation, no limitation other than the Nyquist limit is imposed on the ratio of corner to sampling frequency. For an nth order filter, the number of voltage inverter switches is (n+1)/4 to (n+1)/2. A 3.4 kHz third-order Chebyshev low-pass CMOS circuit is described in detail. It uses only one voltage inverter switch implemented by a switched op amp integrator. The sampling frequency is 24 kHz, the dynamic range exceeds 70 dB and the chip area is 1.2 mm/SUP 2/. A CMOS voltage inverter switch, which has zero DC power and occupies only 0.09 mm/SUP 2/ is presented, whose dynamic range exceeds 85 dB. This allows low power switched capacitor filters without operational amplifiers and with a frequency capability approaching the megahertz range.

Sequential voltage-inversion principle for switched-capacitor filters

For a special class of switched-capacitor filters, voltage-inverter switches are needed. It is shown how several voltage-inverter switches can be realised using only one operational amplifier.