Abstract: Optical spectroscopy is a widely used method to identify the chemical composition of materials and the characteristics of optical signals. Silicon based integrated photonics offers a platform for many optical functions through microelectromechanical systems (MEMS) and microoptoelectromechanical systems (MOEMS), silicon waveguides, integrated CMOS electronics and hybrid integration of compound semiconductor elements for optical gain. Accordingly, it would be beneficial to provide advanced optical tools for techniques such as optical spectroscopy and optical tomography exploiting MOEMS to provide swept filters that offer improved performance, increased integration, reduced footprint, reduced power consumption, increased flexibility, reconfigurability, and lower cost. Further, such MOEMS elements can support the provisioning of swept optical sources, swept filters, swept receivers etc. in the planar waveguide domain without free space optics.

Abstract: An electric arc welder including a high speed switching power supply with a controller for creating high frequency current pulses with negative polarity components through the gap between a workpiece and a welding wire advancing toward the workpiece, where the pulses and a background current defining a series of weld cycles. A wave shape generator defines the shape of the pulses and the background current including a controlled ramp up and/or ramp down in each of said cycles, and a circuit to change the shapes of the pulses and/or background current in a repeating pattern in each of the weld cycles, including a negative current in at one of said pulses. The shape change in a cycle can be between first and second shapes or by a rhythmic AC modulation.

Abstract: An adaptive slope generator can include a current mirror configured to receive a multiplied current that varies as a function of an output voltage and a switching frequency of a switching current. The output voltage can characterize the switching current provided to a load coupled to an inductor. The current mirror can also be configured to receive an oscillation current. The oscillation current can have an amplitude that corresponds to the switching frequency of the switching current. The current mirror can be further configured to generate an output current substantially equivalent to the product of the oscillation current and the output voltage. The adaptive slope generator can also include a ramp generator configured to generate a compensation signal based on the output current. The compensation signal can have a sawtooth shape and a slope that varies as a function of the output voltage.

Abstract: An integrated circuit, method of controlling power supplied to semiconductor devices, a method of designing an integrated circuit and a computer program product are disclosed. The integrated circuit comprises: a semiconductor device for handling data; a power source for powering said semiconductor device, said power source comprising a high voltage source for supplying a high voltage level and a low voltage source for supplying a low voltage level; a plurality of switching devices arranged between at least one of the high or low voltage sources and the semiconductor device. There is also a control device for controlling a first set of the plurality of switching devices to connect one of the high or low voltage sources to the semiconductor device and for controlling a second set of the plurality of switching devices to connect the one of the high or low voltage sources to the semiconductor device.

Abstract: A low power servo-controlled single clock ramp generator (100) includes a fast switched comparator (102), charge pump (110) and voltage-to-current converter (120) connected to provide a feedback control mechanism under control of a pulse comparison clock signal (pulse_comp) and a reset pulse clock signal (rst_pulse) that are generated from a single input clock signal (clkin) so that there are well defined time intervals between pulses in the pulse comparison clock signal and the reset pulse clock signal, thereby providing a ramp signal (Vramp_out) having a stable, frequency-independent amplitude that is not limited by the reference voltage.

Abstract: The circuit for fixing the peak current of an inductor includes an operating current, a ramp-type boost converter and a comparator. The magnitude of the operating current is proportional to that of the voltage source of the inductor. The ramp-type boost converter is connected to the operating current. One input end of the comparator is connected to a reference voltage, and the other end is connected to the output of the ramp-type boost converter. The output of the comparator is connected to the gate of a power transistor, which controls the turn-on time of the inductor.

Abstract: An input circuit includes an input signal transmission circuit configured to output a first transmission signal at a first output node in response to an input signal at an input node, and a Schmitt trigger inverter configured to output a second transmission signal at a second output node in response to the first transmission signal. The input signal transmission circuit includes a voltage drop element connected to the input node and configured to provide a voltage drop between the input node and a transistor having a gate to which a first supply voltage is applied.

Abstract: Zero crossings for a non-symmetrical VIN may be determined by first amplifying and clipping VIN to create a non-symmetrical square wave whose zero crossings are those of VIN. A selected polarity edge of the non-symmetrical square wave may be taken as a 0° indicator and is used to create a fundamental sawtooth ramp of the same frequency and in phase with VIN. The fundamental sawtooth ramp starts at zero volts, linearly ramps to some peak and is AC coupled to a comparator whose other input is zero volts. That creates a square wave that is symmetrical as to its half-cycles, and whose every other edge is synchronous with the start of the fundamental sawtooth ramp, and whose intervening edges occur in the middle of the ramp. The intervening edge is detected and taken as a 180° indicator.

Abstract: A circuit arrangement for switching an inductive load (12, 12a-d) with connections to a power supply source (11, 11?, 11?) by means of which an exciter voltage can be applied to the inductive load (12, 12a-d) in a switched-on state is described, comprising switching means by means of which, depending on a control signal, a power circuit comprising the inductive load (12, 12a-d) and the power supply source connections, can be closed when switched from the switched-off to the switched-on state and opened when switched from the switched-on to the switched-off state, furthermore comprising a first diode (15, 15a-d, 15a?-c?, 15a?-c?) arranged in parallel with the inductive load (12, 12a-d) and so as to block in the switched-on state. This present invention is characterized in that an additional commutation inductance (18) is provided which is arranged in parallel with the inductive load (12, 12a-d) and in series with the first diode (15, 15a-d, 15a?-c?, 15a?-c?).

Abstract: A circuit configuration for pulsed current regulation of inductive loads includes a freewheeling configuration which is connected in parallel with the inductive load and has a current-measuring device in order to measure current exclusively while a switching device is in an open state. This avoids an otherwise customary shunt resistor and associated power loss.

Abstract: In a circuit, switch (1) switches a current from a reference voltage terminal through an inductive element (3). The energy stored in the magnetic field associated with the inductive element when a current is flowing is transferred on interruption of the current either capacitively or inductively to an energy storage element (4). The stored energy is then returned to re-energize the inductive element (3) when the current flow is restored by the switch (1).

Abstract: An apparatus for controlling an electrical appliance coupled with an output terminus and configured to operate in response to an alternating input signal, such as input AC power. The apparatus comprises a reference signal generator for receiving the input signal and generating a reference signal (either V.sub.RAMP or V.sub.CONTROL) in response to the input signal, and a control circuit for controlling connection of the input signal to the output terminus in response to the reference signal and to a user-defined set-point signal. The control circuit is coupled with the reference signal generator and with a set-point terminal. The set-point terminal receives the set-point signal and the control circuit controls connection of the input signal with the output terminus in response to a predetermined relationship between the reference signal and the set-point signal; the apparatus is capable of generating a modified periodically interrupted AC power output based on an AC power input.

Abstract: A television receiver is controlled as to the degree of vertical zoom via a deflection current ramp that varies in slope and which may be delayed to achieve panning. Due to the increased slope when zoomed, the deflection current and the electron beam complete a trace in less time than the normal vertical interval. The deflection current is maintained at one extreme or the other outside the trace interval, and the beam is blanked. A retrace signal generator coupled in a feedback loop with the power supply for the deflection circuit determines the midpoint of the blanking period and generates a fast retrace at or near the midpoint. The feedback loop is arranged to minimize the DC average current in the deflection winding by having a current source responsive to the DC average current for charging a timing ramp that triggers retrace upon reaching a threshold. The slope of the timing ramp varies with DC loading, thus advancing or retarding retrace to center retrace in the blanking interval.