摘要:
A redundant power supply system with several individual power supplies, each connected to one of several power inlets. At least one power supply can be connected to a selectable one of the several power inlets by means of a steering network.
摘要:
A universal modular power supply carrier mounts different sized power supplies within a substantially rectangular body designed for thermal and electromagnetic emissions control. The power supplies are preferably secured within the carrier body. Input connectors may be alternating current or direct current. The output connector may be pin, or blade, and socket with blind mating capability. One or more direct current voltages may be output by the carrier to a motherboard or other electronic circuitry. The universal modular power supply carrier may be contained in a one-size universal electronic equipment cabinet.
摘要:
Operational transconductance amplifiers (OTAs) are combined at their outputs, yielding a single frequency compensation connection point. In a preferred embodiment, the output of each OTA is asymmetric, i.e., they can only source current and the OTA outputs are tied together to a constant current sink. Consequently, the OTA that sources more current controls the voltage of the merged output. This merged output point provides a voltage output that may be used as a frequency compensation point.
摘要:
A low cost high frequency electronic dimming ballast for gas discharge lamps is disclosed which eliminates the need for external primary inductance or choke coils by employing leakage inductance of the transformer. The system is usable with either fluorescent or high intensity discharge lamps and alternate embodiments employ the push-pull or half-bridge inverters. Necessary leakage inductance and tuning capacitance are both located on the secondary of the transformer. Special auxiliary windings or capacitors are used to maintain necessary filament heating voltage during dimming of fluorescent lamps. A clamping circuit or auxiliary tuned circuit may be provided to prevent component damage due to over-voltage and over-current if a lamp is removed during operation of the system.
摘要:
A low cost, high frequency, solid-state dimmable fluorescent ballast is disclosed which utilizes a resonant bridge inverter to provide high frequency sinusoidal power to the lamps. One embodiment of the invention includes auxiliary windings connected to the filaments of the lamps to be powered which utilize the inductance of the resonant bridge inductor coil to maintain the voltage across the filaments during dimming. A clamping circuit or auxiliary tuned circuit may be provided to prevent damage due to an over-voltage and over-current condition upon removal of a lamp during operation of the system. In an alternative embodiment, the auxiliary windings, are replaced by capacitors across each of the lamps to be powered. This also eliminates the need for the clamping circuit. If desired, a current splitting capacitance system may be used. Pulse width modulation of the inverter drive or variable AC or DC power supply input may be used to accomplish dimming.
摘要:
A two-wire ballast arrangement for fluorescent lamp dimming is disclosed in which a modified transformer utilizing the natural leakage inductance associated with ballast transformers is used to achieve full-range fluorescent tube dimming at substantially constant filament heating voltage. Additional auxiliary secondary windings are disposed in predetermined spaced relationship to the primary winding and the main secondary winding to create a "tapping" effect in the magnetic flux. The mutual leakage inductances of the auxiliary secondaries in relation to the primary and the main secondary is utilized in a manner such that as the voltage is decreased to the primary, the voltage of the auxiliary secondary windings remains substantially constant to hold the filament heating voltage substantially constant. Embodiments are disclosed for use either with conventional 50/60 Hz or at high frequency, i.e. above 400 Hz.
摘要:
A method and system for monitoring latent faults in power supplies may include a variable voltage source and a logic module that may be coupled to an OR FET circuit. The monitoring system may also include comparators for measuring a voltage drop across a FET and, based upon a value of the voltage drop, may determine a latent fault, such as a short circuit or open circuit across the FET.
摘要:
The present invention is a method and system for providing improved isolation for power supplies while minimizing power dissipation. A body diode of a MOSFET may be utilized with a comparator circuit. The comparator circuit may detect current flow across the MOSFET and may turn the MOSFET on. This may shunt the diode with a low drain to source resistance limiting power dissipation across the diode to an amount of the drain to source current squared (Ids2) times the drain to source resistance of the MOSFET when on (RDSon). Use of the comparator circuitry may reduce the time delay associated with turning the MOSFET off to prevent a high reverse inrush current within a power supply.
摘要:
Embodiments of the invention include a test circuit having an auxiliary low power test signal generator, filters, and a detector to test a power switch. The generator sends an auxiliary low power test signal having a different frequency than a power signal for the switch to an input of the switch. The detector detects the auxiliary low power test signal at an output of the switch. Test circuit filters are used to filter out the power signal from reaching the auxiliary low power test signal generator or the detector circuit. A circuit of the test circuit is tuned to the test signal's different frequency to ensure that the detector only detects the test signal when the switch is in one position. Thus, by detecting or sensing the test signal across the switch, the detector can detect whether the switch is operating properly.
摘要:
A universal modular power supply carrier mounts different sized power supplies within a substantially rectangular body designed for thermal and electromagnetic emissions control. The power supplies are preferably secured within the carrier body. Input connectors may be alternating current or direct current. The output connector may be pin, or blade, and socket with blind mating capability. One or more direct current voltages may be output by the carrier to a motherboard or other electronic circuitry. The universal modular power supply carrier may be contained in a one-size universal electronic equipment cabinet.