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In this paper, oscillation-based built-in self-test method is used to diagnose catastrophic and parametric faults in integrated circuits. Sallen–Key low pass filter and high pass filter circuits with different gains are used to investigate defects. Variation in seven parameters of operational amplifier (OP-AMP) like gain, input impedance, output impedance, slew rate, input bias current, input offset current, input offset voltage and catastrophic as well as parametric defects in components outside OP-AMP are introduced in the circuit and simulation results are analysed. Oscillator output signal is converted to pulses which are used to generate a signature of the circuit. The signature and pulse count changes with the type of fault present in the circuit under test (CUT). The change in oscillation frequency is observed for fault detection. Designer has flexibility to predefine tolerance band of cut-off frequency and range of pulses for which circuit should be accepted. The fault coverage depends upon the required tolerance band of the CUT. We propose a modification of sensitivity of parameter (pulses) to avoid test escape and enhance yield. Result shows that the method provides 100% fault coverage for catastrophic faults. [ABSTRACT FROM AUTHOR]

This paper deals with the synchronization problem of harmonic oscillatory systems, such as two- and three-phase harmonic oscillators. Synchronization between referent and controlled harmonic oscillators, based on amplitude and phase control, is pursued by employing a variable structure control system. Synchronization is achieved by organizing sliding mode along the intersection of two appropriate nonlinear sliding surfaces, individually providing amplitude and phase identity. In case of three-phase harmonic oscillator synchronization an additional symmetry condition arises, which is handled by introduction of another sliding surface. Parameter perturbations and external disturbances are taken into consideration in control system design. Variable structure controllers for two- and three-phase synchronization are designed, which provide sliding mode along the intersection of sliding surfaces in finite time in spite of present disturbances. Ideal sliding dynamics is proved to be insensitive to internal and external disturbances resulting in an ideal harmonic response. Mathematical analysis as well as experimental and simulation results are presented. [ABSTRACT FROM AUTHOR]

An oscillation based test method is a simple and in some cases quite efficient method for producing a go-no go test. In this approach, the circuit is transformed into an oscillator during the test mode and the frequency of oscillation is measured and compared to a reference value obtained on a known good circuit operating in the same conditions. The main drawback is that only some parts of a complex analogue system can be transformed into oscillators and hence be tested by the oscillation test approach. In this paper, we extend their application to stimulus generation of a built-in self-test. Oscillation test structures of switched-capacitor and active RC filters are considered. Simple ways of changing the oscillation frequency are discussed. [ABSTRACT FROM AUTHOR]

This paper describes two approaches to implementing third-order oscillators. The first approach proposes a third-order oscillator using transconductors and capacitors. They are cascaded as two lossy and one lossless integrator circuit. This approach is a feedback from transconductance gain = 2. This first circuit is based on a basic transconductor with a simple configuration including 16 ransistors, four current sources and three capacitors. The second approach proposes a third-order oscillator using transconductors, capacitors and a transresistor circuit. These are cascaded as lossy integrator circuits and are fedback with voltage gain = 8. This voltage gain can be designed using a transconductor circuit and a transresistor circuit. This second circuit consists of 18 transistors, four current sources and three capacitors. Since both circuits use no resistors, they are suitable for further fabrication. These circuits use a ±3V power supply. [ABSTRACT FROM AUTHOR]

The aim of this paper is to design a sinusoidal oscillator by using sliding mode control theory. From a control point of view, we first conceive a second-order linear system as a controlled plant, then a proper control law is designed for a sinusoidal oscillator. The amplitude of the sinusoidal signal is well regulated. It is invariant to initial condition and robust to parameter variation. The desired oscillation amplitude and frequency can be determined independently. In addition, the design of a sinusoidal oscillator with parameter variations is also taken into consideration. The proposed method is derived and simulation results are given to verify the analysis. [ABSTRACT FROM AUTHOR]

This paper deals with the design and implementation of a new multi-purpose function generator, in which the frequency of oscillation can be controlled by an external signal. It provides different types of waveforms such as sine, square, triangle, TTL square and monitor waveforms. The TTL square and monitor waveforms are provided for use respectively as a clock to logic circuits and for various timebase applications. The function generator provides low-distortion outputs from 1 mHz to 1 MHz in nine controlled ranges. The output waveforms are calibrated 0-20 V pk-pk with DC offset control. Input and output impedances are 10 kΩ and 600 Ω, respectively. [ABSTRACT FROM AUTHOR]

An automatic digital Q-meter suitable for measuring low Q-factors at low frequencies is described. It uses a microcomputer. In a conventional digital Q-meter, the number of damped oscillations which occurs in the time interval between the initial peak and the damped peak exp (-π) times smaller than the first one, corresponds to the numerical value of the Q-factor. For small Q-factors a considerable error occurs in this procedure, and the error can be eliminated by the procedure presented in this paper. [ABSTRACT FROM AUTHOR]

The modified peniotron is expected to have an extremely high conversion efficiency and a higher output power in centimetre and millimetre wave regions than those of the original peniotron. This paper describes the design considerations of a test tube used for experimental confirmation of its promising features, and shows some experimental results in connection with electron beam and oscillation characteristics obtained up to the present. [ABSTRACT FROM AUTHOR]

This paper presents a sinusoidal oscillator whose frequency of oscillation bears a linear relationship with the controlling voltage V[sub x]. The basic configuration incorporates two four-quadrant analogue multipliers in conjunction with RC network of which two capacitors are grounded. The circuit is found to show an ultra-low distortion output. The realization of the basic configuration uses two grounded capacitors which are suitable for LSI implementation of the oscillator circuit. [ABSTRACT FROM AUTHOR]