Abstract:
A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as a converter in LED-based light bulbs. The power stage may be operated by a controller to maintain a desired current output to the LED load. The controller may operate the power stage by monitoring a start and end of a reverse recovery time of the BJT. Information regarding the start and end of the reverse recovery time may be used in the control of the power stage to improve efficiency of the power stage.
Abstract:
A self-oscillating resonator (SOR) may be used to control current through light emitting diodes (LEDs). The SOR may be started and stopped by a controller coupled to a transistor switch in the SOR. The controller may output a control signal that starts and stops the SOR by coupling a supply voltage or a ground to a base of the transistor switch in the SOR. Additional control over the current output to the LEDs may be gained through a resistive DAC coupled to the SOR and duty cycling the SOR.
Abstract:
Multiple measurements may be obtained via a single pin of an integrated circuit (IC) to set multiple control parameters of a light emitting diode (LED) controller within the IC. For example, a first input signal may be applied from the IC to two or more components via a single IC pin. A first output signal may be obtained from the two or more components via the single IC pin. A second input signal may be applied from the IC to the two or more components via the single IC pin, and a second output signal may be obtained from the two or more components via the single IC pin. A first parameter and a second parameter of the two or more components may be calculated based, at least in part, on the first output signal and the second output signal obtained via the single IC pin.
Abstract:
A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as a converter in LED-based light bulbs. The power stage may be operated by a controller to maintain a desired current output to the LED load. The controller may operate the power stage by monitoring a start and end of a reverse recovery time of the BJT. Information regarding the start and end of the reverse recovery time may be used in the control of the power stage to improve efficiency of the power stage.
Abstract:
A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as for LED-based light bulbs. The BJT may be switched on and off from a controller coupled to two terminals of the BJT. Through the two terminals, the control IC may dynamically adjust a reverse recovery time period of the BJT. The reverse recovery time period may be adjusted by changing an amount of base charge that accumulates on the BJT. Additional, the reverse recovery may be controlled through the use of a reverse base current source applied to the BJT after beginning switching off the BJT.
Abstract:
A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as for LED-based light bulbs. The BJT may be switched on and off from a controller coupled to two terminals of the BJT. Through the two terminals, the control IC may dynamically adjust a reverse recovery time period of the BJT. The reverse recovery time period may be adjusted by changing an amount of base charge that accumulates on the BJT. Additional, the reverse recovery may be controlled through the use of a reverse base current source applied to the BJT after beginning switching off the BJT.