Abstract: A keyboard includes a circuit board having an upper surface, a lower surface opposite to the upper surface, and a plurality of cut-out portions, a plurality of key modules positioned on the upper surface and over the plurality of cut-out portions, and a plurality of light sources installed on the lower surface of the circuit board, wherein at least a portion of at least one light source is positioned in a corresponding cut-out portion. Each light source includes a light emitting portion coupled to the second circuit layer. At least some of the light emitting portion is disposed in the cut-out portion beneath and bounded by the key module.

Abstract: A keyboard includes a circuit board having an upper surface, a lower surface opposite to the upper surface, and a plurality of cut-out portions, a plurality of key modules positioned on the upper surface and over the plurality of cut-out portions, and a plurality of light sources installed on the lower surface of the circuit board, wherein at least a portion of at least one light source is positioned in a corresponding cut-out portion. Each light source includes a light emitting portion coupled to the second circuit layer. At least some of the light emitting portion is disposed in the cut-out portion beneath and bounded by the key module.

Abstract: A keyboard includes a circuit board having an upper surface, a lower surface opposite to the upper surface, and a plurality of cut-out portions, a plurality of key modules positioned on the upper surface and over the plurality of cut-out portions, and a plurality of light sources installed on the lower surface of the circuit board, wherein at least a portion of at least one light source is positioned in a corresponding cut-out portion. Each light source includes a light emitting portion coupled to the second circuit layer. At least some of the light emitting portion is disposed in the cut-out portion beneath and bounded by the key module.

Abstract: A keyboard includes a circuit board having an upper surface, a lower surface opposite to the upper surface, and a plurality of cut-out portions, a plurality of key modules positioned on the upper surface and over the plurality of cut-out portions, and a plurality of light sources installed on the lower surface of the circuit board, wherein at least a portion of at least one light source is positioned in a corresponding cut-out portion. Each light source includes a light emitting portion coupled to the second circuit layer. At least some of the light emitting portion is disposed in the cut-out portion beneath and bounded by the key module.

Abstract: A universal power supply system allows each board mounted DC power module or each AC/DC power supply device therein having identical dimensions and appearance to further have a specification setting circuit. When the board mounted DC power module or the AC/DC power supply device is plugged in a backboard module, the specification setting terminal outputs a specification identification signal to a monitoring circuit of the backboard module. As built in with a specification mapping table, the monitoring circuit can compare the specification identification signal to find a model number corresponding to the signal, and automatically sets a critical current value or critical power value of each board mounted DC power module for over-current protection or over-power protection. Accordingly, the universal power supply system can be adapted to different board mounted DC power modules or AC/DC power supply devices without redesigning the backboard module.

Abstract: A universal power supply system allows each board mounted DC power module or each AC/DC power supply device therein having identical dimensions and appearance to further have a specification setting circuit. When the board mounted DC power module or the AC/DC power supply device is plugged in a backboard module, the specification setting terminal outputs a specification identification signal to a monitoring circuit of the backboard module. As built in with a specification mapping table, the monitoring circuit can compare the specification identification signal to find a model number corresponding to the signal, and automatically sets a critical current value or critical power value of each board mounted DC power module for over-current protection or over-power protection. Accordingly, the universal power supply system can be adapted to different board mounted DC power modules or AC/DC power supply devices without redesigning the backboard module.