| 摘要 |
A control circuit for a light emitting diode for indicating power-on in a normal operating mode, power-on in a sleep mode, and power-off, the control circuit includes: a first voltage source having a DC voltage that is greater than a nominal forward voltage drop of the light emitting diode, the first voltage source connected to a first resistor in series with an anode of the light emitting diode; a second voltage source having a DC voltage that is greater than the DC voltage of the first voltage source; a first transistor connected between a cathode of the light emitting diode and ground; a control signal connected to an input of the first transistor; a second transistor connected between the first voltage source and the second voltage source, wherein an output of the first transistor is connected to an input of the second transistor. |
