Patent classifications
H05B41/2858
Enhanced variable control, current sensing drivers with zeta scan
An electronic lighting system with a driver includes transformers that are dedicated to particular lamp receptacles that include interloper diode and resistor sets that fine tune the functioning of the driver. A buck converter and power factor correction, and a zeta scan are included. A comparator circuitry receives an external control signal and compares it to feedback from the output side of the circuitry, and thereby controls a Pulse Width Modulation (PWM) circuitry, which cooperates with feedback-based MOSFETs and a MOSFET gate driver circuit. This aids in dimming capabilities, recognizes and corrects for outages and recognizes and corrects for changes in the different size lamps that a user may install.
Electronic circuit for protecting a load against over-voltage
An electronic circuit for protecting a load against over-voltage is disclosed. The electronic circuit comprises an input port for receiving a voltage and an output port for feeding the voltage to the load. The electronic circuit further comprises a switching unit arranged to switch on and off the voltage from the input port. Moreover, the electronic circuit comprises a capacitive component arranged to receive the voltage when the switching unit is switched on and is otherwise arranged to feed voltage to the output port. Furthermore, the electronic circuit comprises a comparing unit configured to control the switching unit to be switched off when a value at the output port exceeds a first threshold; and to control the switching unit to be switched on when the value is below a second threshold.
Light source apparatus, discharge lamp driving method, and projector
In at least one embodiment, a light source apparatus includes a discharge lamp with a pair of electrodes and a driving unit that supplies a driving current to the pair of electrodes. The driving unit includes an AC supplier that supplies an alternating current to the pair of electrodes and a DC supplier that supplies a direct current to the pair of electrodes. The AC supplier is configured to alternately repeat an AC supply section in which the alternating current is supplied and an AC stop section in which the supply of the alternating current is stopped. The DC supplier is configured to supply the direct current during a period corresponding to the AC stop section. A frequency of the direct current is not lower than 10 Hz and not higher than 1 kHz.