Negative current sensing method for multi-channel LED driver

    公开(公告)号:US09693404B1

    公开(公告)日:2017-06-27

    申请号:US15266211

    申请日:2016-09-15

    IPC分类号: H05B33/08 H02M1/088 H02M1/00

    摘要: A multi-channel LED driver is provided with a negative current sensing method for inherent output short circuit protection, as well as protection from output misconnection. A plurality of power converters are configured to drive respective LED arrays, each power converter respectively comprising a first stage configured to provide current through a primary winding of an isolation transformer. A second stage has a capacitor coupled in parallel with a secondary winding of the isolation transformer, a current sensing resistor coupled between the secondary winding and a circuit ground for the second stage. A filtering circuit is coupled on a first end to a node between the secondary winding and the current sensing resistor, and on a second end to the circuit ground. A feedback circuit is coupled between the first stage and the filtering circuit, and configured to deliver a control signal corresponding to current through the secondary winding.

    Conduit knockout interface device for connecting a power over ethernet cable to an LED luminaire

    公开(公告)号:US09801262B1

    公开(公告)日:2017-10-24

    申请号:US15146104

    申请日:2016-05-04

    发明人: John Helms

    IPC分类号: H05B37/02 H05B33/08 F21K99/00

    摘要: A power over Ethernet (PoE) interface device includes a knockout adapter. The knockout adapter is configured for mounting to a conduit knockout opening in an LED luminaire. The interface device includes a power assembly having an input section and an output section. The power assembly is connected to the knockout adapter such that the output section is positioned inside the luminaire when the knockout adapter is mounted to the luminaire. The power assembly further includes a data connector mounted to the input section. The data connector is configured to receive PoE signals from a data cable coupled to the data connector. Power output terminals are mounted to the output section and electrically coupled to the data connector. The power output terminals may be configured to couple the PoE signals from the data connector to an LED light source in the luminaire.

    Slide adjustable hinge and latch securement for a light emitting diode (LED) fixture retrofit kit

    公开(公告)号:US10794576B1

    公开(公告)日:2020-10-06

    申请号:US16529960

    申请日:2019-08-02

    发明人: John Helms

    摘要: A hinge apparatus and method of use are provided for securing to a slide of a retrofit kit and to an opening of a fixture. The hinge apparatus includes a hinge configured to couple to the opening of the fixture, a top section coupled to the hinge, a lower section coupled to the top section and having a cavity formed therebetween, the cavity configured to be coupleable to the retrofit kit, a hinge brake securement device coupled to the top section, a neck extending outwardly from the hinge brake securement device, a hinge brake coupled to the neck, and a notch coupled to the hinge brake, the notch configured to be receivable at the slide of the retrofit kit.

    LED driver circuit with step configurable output

    公开(公告)号:US09807830B1

    公开(公告)日:2017-10-31

    申请号:US15209851

    申请日:2016-07-14

    发明人: Wei Xiong John Helms

    IPC分类号: H05B33/08

    摘要: An LED driver apparatus provides discrete output current configuration. User interfaces such as dip switches enable user selection of output current settings. LED driver circuitry includes an inverter, a primary transformer winding coupled to the inverter switches and providing resonant inductance, and a secondary transformer winding coupled on a first end to an output rectifier. Various circuit branches are coupled in parallel between the output rectifier and the secondary winding, each including a switching element driven between open and closed states associated with the user-selected output current setting. The circuit branches may be coupled to respective secondary winding taps, wherein output current is regulated according to an effective turns ratio defined by the closed circuit branch. Alternatively, the circuit branches may be coupled to one end of the secondary winding but include current limiting capacitors, wherein one or more closed circuit branches define an equivalent capacitance and associated output current.