| 摘要 |
Techniques and corresponding circuitry are disclosed for providing active current sharing in lighting applications. The techniques can be used, for instance, to minimize or otherwise reduce current differences between parallel LED strings of a given lighting apparatus while further minimizing or otherwise reducing power dissipation. In some embodiments, an active current sharing circuit is provided that includes a series-pass sub-circuit, such as a transistor or transistor circuit (or other active series-pass circuit), for each LED string. In addition, each string has a current sense sub-circuit for sensing current of that string. A monitor and control sub-circuit operates in conjunction with the series-pass sub-circuit to maintain the sensed current equal to a common reference level. In some embodiments, the common reference level is controlled to maintain the lowest series-pass element voltage close to or equal to zero volts (-0.25VDC to +0.25VDC). |
