Abstract: A circuit arrangement is suggested for the operation of a gas-discharge lamp on a direct-current source, particularly in a motor vehicle. In order to feed the gas-discharge lamp (36) with constant power for the purpose of achieving a uniform brightness of the lamp, a push-pull inverter circuit is provided with an output power regulator (11), two transistors (12, 13) and a transformer (22) which carries out an inversion of the available fluctuating direct voltage of a direct-current source (18) into an alternating voltage of suitable level and frequency. The inverter (11, 12, 13) receives, at its control inputs, control signals which are derived from the lamp voltage (U) and the lamp current (I) for supplying the gas-discharge lamp (36) with substantially constant power in continuous operation.

Abstract: A circuit arrangement for regulating the high-voltage supply of an electrostatic filter for internal combustion motors whose high-voltage output stage (2) is controlled by a pulse-width modulator (3). The high-voltage output stage (2) contains a diode blocking oscillator which gives off a output voltage (U.sub.A) of several kV on the output side. The pulse-duty factor of the output voltage (U.sub.A) is changed as a function of the output current or the output voltage and while taking into account a maximum allowable power. The soot filter (1) can be constantly operated in an optimum operating range in this manner.

Abstract: An arrangement for rapid switching of an electromagnetic load includes a series arrangement of a switching device with the electromagnetic load, a relief diode arranged in parallel with the electromagnetic load, and a capacitor arranged in parallel to the switching means. Another switching device is arranged parallel to the capacitor and controls the operation of the latter, while an additional switching device is arranged in series with the relief diode and controls the operation of such relief diode. An operating arrangement for controlling the various switching devices issues various control signals at least some of which depend on electric signals derived from the switching arrangement. During the operation of the switching arrangement, the operating arrangement selectively makes the various switching devices conductive and non-conductive in a predetermined sequence to enhance the speed of switching of the electromagnetic load between its two end states.

Abstract: To equalize current flow through a pair of chokes supplying a d-c load from a d-c source, and, if desired, to limit current flow through either a single choke or both to a predetermined maximum value, without using measuring shunts, the voltage drop through the choke itself is being measured by summing circuits, which may form the algebraic sum or difference, respectively, of the voltages across the chokes, the sum or difference signals then being passed through low-pass filters to form signals representative of inductive voltage difference of two chokes, or of the voltage drop through one or both of them, which signals are then applied to respective regulators which, in turn, control the duty cycle of one or two semiconductor switches, respectively connected in series with the respective chokes.