INDUCTORLESS LED DRIVER
Typically, the current source is arranged in series with the SSL device, thereby directly controlling the current through the SSL device. During the first phase , the input voltage source is coupled to the constant voltage load e. In the first phase , the input voltage Vin at the voltage source is equal to the sum of the voltage drop Vcap at the capacitor bank , the voltage drop Vled at the constant voltage load and the voltage drop Vsrc at the load current source Accordingly, the housing is typically designed to enable heat generated by the light source to be conducted away from the light source, and out of the assembly as a whole. Furthermore, the light bulb assembly typically comprises an electrical connection module e. The light bulb assembly of claim 9 , wherein the control unit is continuously modifying the commutation cycle rate.
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Furthermore, the light bulb assembly typically comprises an electrical connection module e. In accordance to the objectives of the disclosure a SSL light bulb assembly has been achieved.
US20130257277A1 – High Efficiency Inductor-less Off-Line LED Driver – Google Patents
The varying input voltage may have been derived from a mains supply e. In the next cycle of the input voltage, the bi-directional switch circuit will essentially repeat the same operations to control the LED current. For this purpose, the plurality of switches of the power converter may switched according to different modes, wherein each mode allows for a different conversion ratio between the input voltage Vin being the rectified input voltage waveform from the invuctorless power supply and the output voltage Vout, with the output voltage Vout being the sum of the voltage Vled across the SSL device and the voltage Vsrc across the current sourcei.
The selected operation mode is implemented by alternating between the first phase and the second phase at a commutation cycle rate.
The plurality of operational modes of the power converter provides a corresponding plurality of different conversion ratios between the input voltage and the output voltage, respectively. As outlined above, in step the process steps— – are repeated by going back to step at inducttorless pre-determined execution rate, i.
In the case of a solid state light source 6the driver circuit 8 is configured to provide a controlled direct drive current to the light source 6. The execution rate may be e. The control unit may then drive the current source so as to provide the desired current flowing through the SSL device, thereby generating the desired light intensity which is in general proportional to the SSL drive current.
A rectifier circuit has inductorlezs first input coupled to the capacitor and a second input coupled to the second AC power source input terminal, and first and second outputs, wherein AC input power is rectified into DC output power across the first and second rectifier outputs.
Lex driver circuit of claim 27wherein the control unit is continuously modifying the commutation cycle rate. Furthermore, all statements herein providing principles, aspects, and embodiments of the disclosure, as well as specific examples thereof, are intended to encompass equivalents thereof. The power converter disclosed firstly comprises an input port to receive a rectified input voltage, a first switch, wherein a first terminal of the switch is connected to the input port and a second terminal of the first switch is connected to a first output port, and a first capacitor, wherein a first terminal is connected to the input port and a second terminal is connected to an anode of a first diode to a cathode of a second diode and to a first terminal of a second capacitor.
It should be noted that an operational mode ijductorless comprise more than two phases which are executed within each cycle of the operational mode. It should be noted that the current sourcewhich has the function of a controller of the current eld the SSL device may be combined lled the switches S1, S2, etc.
It is designed to drive EL lamps of up to 1. The DC input voltage may e.
USA1 – High Efficiency Inductor-less Off-Line LED Driver – Google Patents
The bi-directional switching circuit may alternatively include a first branch and a second branch coupled in parallel, with the branches each including a switching element and a diode having inductorlses inverse polarities. Each mode comprises a first phase phase inductorleas typically used for charging the capacitorsand a second phase phase lec typically used for discharging the capacitors It should be noted that a driver circuit may be configured to drive two SSL devices in parallel.
A further object of the disclosure is to provide a small, low cost driver circuit and power converter thereof extending the usable range of the mains power to high voltage SSL devices as e. The method of claim 40wherein the method is executed at a certain executing rate wherein the execution rate is dependent on a mains frequency.
The meanings identified below do not necessarily limit the terms, but merely provide illustrative examples for the terms. Finally the power converter comprises a insuctorless switch wherein a first terminal is connected to the second output port and a second terminal is connected to ground, and said first and second output ports wherein a load is connected between both output ports.
The method of claim 41wherein the execution rate is a multiple of the mains frequency which allows for an appropriate sampling of the waveform of the input voltage.
A voltage sensor 11 is coupled across the input terminals and may be formed by a voltage divider including resistors R 1 and R 2. The power converter may be implemented as an integrated circuit on a single chip or in a single package, with only the one or more capacitors being external to the integrated circuit.
During the first phase of mode 2, only the switches S1Sa and Sc are closed and the other switches are openthereby charging the capacitors C1 and C2 in parallel. The lower output terminal 16 b may be coupled to circuit ground.
The SSL device may be appropriately coupled, e. The power converter comprises one or more capacitors; a plurality of switches to couple the capacitors lef a plurality of configurations.
In Production View Datasheet Features: Examples for such light sources 6 are a solid state light source 6such as a light emitting diode LED or an organic light emitting diode OLED the latter technology is referred to as solid state lighting, SSL.
Each cycle may be repeated at the commutation cycle rate f.