| 摘要 |
An LED constant-current driving device. The LED constant-current driving device comprises a rectification module (10), a constant-current module, and a lighting module (70). The lighting module (70) comprises a plurality of LED units (701, 702, 703, 704). An output end of the rectification module (10) is connected to the lighting module (70). The constant-current module is connected to the lighting module (70). The constant-current module comprises a plurality of current-limiting units (51, 52, 53, 54) and a sampling unit (20). Each current-limiting unit (51, 52, 53, 54) comprises a resistor (205, 206, 207, 208), a voltage-regulator tube (301, 302, 303, 304), a triode (501, 502, 503, 504), and a transistor (601, 602, 603, 604). In each current-limiting unit (51, 52, 53, 54), a drain of the transistor (601, 602, 603, 604) and one end of the resistor (205, 206, 207, 208) are jointly connected to an output end of the corresponding LED unit (701, 702, 703, 704); a gate of the transistor (601, 602, 603, 604) is connected to the other end of the resistor (205, 206, 207, 208), a negative end of the voltage-regulator tube (301, 302, 303, 304) and a collector of the triode (501, 502, 503, 504); a source of the transistor (601, 602, 603, 604) and a base of the triode (501, 502, 503, 504) are jointly connected to the sampling unit (20); and an emitter of the triode (501, 502, 503, 504) and a positive end of the voltage-regulator tube (301, 302, 303, 304) are connected and then are grounded. The LED constant-current driving device has a small size and low cost, and also has a high power factor. |
