(Fluorescent lamps cannot be operated on continuous direct current, since mercury ions accelerate in the axial electric field as they are formed, depleting the mercury in the discharge, which accumulates at the cathode.) As in all gas discharge lamps, there are power losses in the ballast that...
FIG. 1 is a schematic diagram of an electronic ballast, including a timed switch, in accordance with the invention in conjunction with a fluorescent lamp; FIGS. 2, 3 and 4 are alternate embodiments of the timed switch in FIG. 1; and ...
A current controlled dimmer for controlling the output intensity of a fluorescent lamp with a magnetic ballast. The current controlled dimmer generates an AC current which follows the shape of the AC line voltage for the fluorescent lamp. The light intensity output of the fluorescent lamp is contro...
In another aspect of the invention, FIG. 4 shows a schematic diagram. DC power supply426supplies power to the various components depicted in FIG. 4 including controller428, fluorescent ballast422, color/brightness sensors420, Red LED control430, Green LED control432, Blue LED control434, and LE...
FIG. 3 is a circuit schematic diagram, partly in functional block form, of an electronic ballast for gaseous discharge lamps constructed according to the present invention; FIG. 4 is schematic diagram, partly in functional block form, of the timing and frequency control circuitry of FIG. 3; ...
A fluorescent lamp ballast having an integrated circuit driver which avoids lamp flicker caused by momentary dips in mains voltage during lamp turn on. The anti-flicker scheme within the fluorescent lamp ballast driver distinguishes between operating conditions during and after preheat of the lamp elec...
The down counter 33 then counts down to zero at the Ballast Clock rate. The time for this countdown is the lamp “ON” time. The lamp is “OFF” until the next preset of the down counter 33. [0028] The output of the down counter 33 is coupled to a D flip-flop 34, which is...
FIG. 7 is a schematic diagram of a prior art solid-state ballast utilizing a resonant bridge inverter; FIG. 2 is a schematic circuit diagram of one embodiment of the present invention; FIG. 3 is a simplified schematic diagram of the circuit of FIG. 2; ...
Figure 1 is a schematic circuit diagram showing the conventional topology for a semi-resonant fluorescent ballast; Figure 2 is a waveform diagram illustrating a fixed frame rate and a variable duty cycle, for operation in the high brightness control range; Figures 3a and 3b show two sets of wa...
Apparatus and methods for supporting a lamp. The apparatus may include a ballast, a rigid power distribution unit, and a lamp holder. The lamp holder may be in electrical communicat