Abstract: A circuit for powering a gas discharge lamp from a source of a first frequency AC power has a a first rectifier for converting the first frequency AC power into a first DC power, a capacitor and driver for converting the DC power to a second frequency AC power. A second rectifier is used to increase the power factor for the circuit. A control is provided to disable the second rectifier if the lamp is removed from the circuit.

Abstract: A circuit (100) for powering fluorescent lamps (102, 104 & 106) includes a switch (50) having "open" and "closed" positions. When power is initially applied to the circuit, the lamps are powered at full power to enable them to "strike". After a short period, the power is reduced to the lamp. A control circuit (300) thereafter senses if the switch has been "toggled". If toggled, the power to the lamps is increased, and the lamps brighten. The circuit uses a conventional two-position switch and conventional wiring and avoids the need for additional switches and additional wiring.

Abstract: A circuit for driving gas discharge lamps has a bandpass filter coupled between the output of the inverter and the inverter control. The bandpass filter provides protection against the diode operation of the gas discharge lamps. The bandpass filter is composed of a capacitor and the permeance inductance of a transformer.

Abstract: A transformer (202) has a bobbin (2) which has an inner portion (104) supporting an inner electrical winding (140) and having a magnetic core recess. The inner portion is located within an outer portion (4) supporting an outer electrical winding (40). The inner portion further has an end with a termination connected to the inner winding, an annular recess (126) in which the inner winding is situated, and a channel (132) communicating between the termination end of the inner portion and a remote end of the annular recess. The channel is positioned radially inwardly of the first annular recess and accommodates a portion of the inner winding. By providing the channel radially inwardly of the annular recess, winding wire can extend between the termination end of the inner portion and the remote end of the annular recess across the annular recess without significantly increasing the size of the inner portion and without increasing the gap between the inner and outer portions.

Abstract: An integrated EMI/RFI Filter Magnetic has differential and common mode inductors wound about an I-Core. The I-Core is juxtaposed with an E-Core, with the end surfaces of the E-Core legs facing the I-Core. The magnetic has a substantially closed magnetic path for the differential inductors and the common mode inductors.

Abstract: A circuit (100) for driving an instant-start fluorescent lamp (102) has an inverter (103, 132) and a series-resonant LC oscillator (146, 152). A capacitor (190) begins charging after power-up of the circuit and when its voltage reaches a certain level causes breakdown of a diac (192), which discharges the capacitor into an inverter transistor (132) to trigger operation of the inverter. Re-triggerring of the inverter is prevented by a diode (194) which subsequently discharges the capacitor cyclically, and by a capacitor (186) which enables a transistor (180) at a predetermined time following power-up. The occurrence of a subsequent fault condition causes a capacitor (210) to charge and to enable a transistor (196) which disables the inverter. Charging of the initiating capacitor (190) is prevented by an open circuit between terminal connectors (160, 162) if the lamp is not present.

Abstract: A transformer or inductor bobbin (2) having pins (24) of a rectangular cross-section with complementarily profiled ends (24A, 24B), of which one (24A) is tapered and the other (24B) has a recess (24E). The rectangular cross-section allows the pins to offer greater resistance to bending in the direction of their cross-section's greater dimension (for pulling winding wire from the pins), while offering easier bending in the direction of their cross-section's greater dimension (for clinching to a printed circuit board). The use of pins having complementary profiles at their opposite ends allows the pins to be separated simply and efficiently from a length of material with no material wastage, and the provision of a taper at one end of a pin and a recess at the other end allows easy insertion of the tapered end into a pre-formed printed circuit board hole while the recessed end provides for collection of scraped material during pin insertion into an undersized hole (22) in the bobbin.

Abstract: A network (2) utilizing power conductor distribution and incorporating infra-red (IR) radiation nodes having IR transducers (4, 6, 8). The IR transducers are located in ceiling-mounted lighting fixtures (16, 18, 20) and are connected to power terminals in the lighting fixtures both for powering the IR transducers in operation and for communicating network information. The transducers are thus positioned optimally for good IR communication and require no additional cabling.

Abstract: Data is transmitted on a power line as a momentary interruption of the power at or near the zero crossing of the current. The interruption is preferably a small fraction of the period of the frequency of the power line. The data is transmitted only to those devices in series circuit with the transmitter. The transmitter combines 60 Hz and 120 Hz clock signals with data from a shift register to interrupt current in a predetermined pattern, in which an interruption of both the positive going and negative going zero crossings define a logic "1" and the absence of interruptions is a logic "0." A data prefix identifies succeeding bits as data. The receiver produces a pulse width modulated signal in response to the data.

Abstract: A transformer bobbin (2) having pins (24) extending therefrom is fabricated by winding connecting wire around the pins and pulling the wire until it breaks, then soldering the wire to the pins. The stresses imparted to the pins cause the pins to become mis-aligned when the bobbin material becomes softened during soldering. In order to correct this misalignment the pins are inserted, while the bobbin material is still soft, into holes (36) in a plate (34). The holes are aligned in the desired alignments of the pins and have at their upper ends (38) tapering profiles which contain the mis-aligned pins and guide them into their desired alignments. The pins are retained in the plate until the bobbin material has resolidified and the pins have become fixed in their desired alignments. During this time electrical continuity testing is performed on the soldered transformer.

Abstract: A control circuit (C) for controlling fluorescent lamps (102, 104 & 106) from a switch (S) having "open" and "closed" positions. The circuit senses whether the switch is (i) open, (ii) closed within less than approximately 0.5 seconds of last being opened, or (iii) closed for the first timne or after a time greater than approximately 0.5 seconds after last being opened, and produces one of three output signals respectively dependent thereon. The control circuit uses only a conventional two-position switch and conventional wiring and avoids the need for additional switches and additional wiring.

Abstract: A driver circuit for one or more gas discharge lamps (102, 104, 106) includes: a self-oscillating, series-resonant oscillator (196, 198, 178, 180) for producing a constant-frequency, high-frequency output voltage for application to the lamps; an inductive voltage boost IC (144) for causing the oscillator to produce a temporary excessive boosted output voltage (300 V) when the voltage boost IC is initially activated and a steady-state boosted output voltage (250 V) thereafter, ensuring striking of the lamps and prolonging their life.

Abstract: An arrangement for securing a power transistor (4, 6, 8) or like component which is inserted into a printed circuit board (2) in a vertically downward direction. The printed circuit board is housed in a housing (20, 60) whose lower part (20) has upstanding walls (24, 26) with pairs of vertical slots (4A & 4B, 6A & 6B, 8A & 8B). Spring clips 52 are inserted vertically downwardly so that their legs (52A, 52B) engage in the slots and their center portions (54) urge the transistors toward the upstanding walls so that the housing acts as a heat sink for the transistors, obviating the need for additional components. Also, since all insertion is performed vertically from above, assembly can be performed straightforwardly by an automatic insertion machine, resulting in more rapid assembly and increased reliability.