Solid-state lighting compatible with ballasts and operable with AC mains
View Patent ↗A light-emitting diode (LED)-based solid-state universal lamp using a ballast compatible and AC-mains operable (BA) LED driving circuit with a power factor correction (PFC) and control device operates normally for a regulated power and current from either ballast or AC mains. The BA LED driving circuit is configured to operate in a wide range of input voltages and frequencies, especially for various high voltages and high frequencies associated with various ballasts. With a cycle-by-cycle current control and power switching at a constant on-time and varied off-time, an over-rated surge current is limited, preventing occasional fire hazards occurred in the ballast.
1. A light-emitting diode (LED) lamp, comprising:
a plurality of LED printed circuit boards (LED PCBs);
a light emission portion comprising LED arrays disposed on the plurality of LED PCBs;
a lamp base portion connected to the light emission portion, the lamp base portion comprising electrical connection terminals;
a bridge rectifier connected to the electrical connection terminals, the bridge rectifier configured to convert an alternating-current (AC) input voltage into a direct-current (DC) voltage; and
an LED driving circuit coupled to receive the DC voltage from the bridge rectifier, the LED driving circuit comprising an input filter, a power factor correction (PFC) and control device, a switch controlled by the PFC and control device, a current sensing resistor, a diode, an inductor with its current charging and discharging controlled by the switch, a resistor, an output capacitor in parallel with the resistor and connected to the inductor to build up an output voltage and to power the LED arrays, and a voltage feedback module configured to draw a partial power from the output voltage to sustain an operation of the PFC and control device,
wherein, responsive to detecting a zero current in the inductor within an AC cycle of the AC input voltage, the PFC and control device generates a zero current detection signal to turn the switch on and off with a constant on-time and a varied off-time.
2. The LED lamp of claim 1 , wherein the voltage feedback module comprises a diode.
3. The LED lamp of claim 1 , wherein the inductor in the LED driving circuit is of an autotransformer type.
4. The LED lamp of claim 1 , wherein the inductor in the LED driving circuit is of a transformer type.
5. The LED lamp of claim 1 , wherein the PFC and control device operates in a range approximately between 11 volts, direct current (VDC) and 35 VDC.
6. The LED lamp of claim 1 , wherein the electrical connection terminals comprise four pins comprising a base of G24q, Gx24q, or 2G11.
7. The LED lamp of claim 1 , wherein the electrical connection terminals comprise two pins comprising a base of G23, GX23, or G24d.
8. The LED lamp of claim 1 , wherein the electrical connection terminals comprise two pins comprising a base of GU24, GU10, or GU5.3.
9. The LED lamp of claim 1 , wherein the electrical connection terminals comprise a base of E26, E27, or E39.
10. The LED lamp of claim 1 , wherein the electrical connection terminals comprise a base of G13.