Abstract: A device includes a charge controller to regulate a battery output voltage based on an input voltage and an input current received from a charging circuit. A loop controller monitors the input voltage and the input current to generate a feedback signal to adjust the input voltage to the charge controller.

Abstract: A device includes a charge controller to regulate a battery output voltage based on an input voltage and an input current received from a charging circuit. A loop controller monitors the input voltage and the input current to generate a feedback signal to adjust the input voltage to the charge controller.

Abstract: A power supply circuit is proposed for supplying current to a pair of white LEDs connected in series. The circuit comprises a DC-DC power converter, with a charge pump coupled to the output of the DC-DC power converter. A super capacitor is coupled to the charge pump to be charged to a voltage on top of the converter output in a first mode of operation. The super capacitor is discharged through the pair of LEDs during a second mode of operation. A control stage is provided for switching between the first mode of operation and the second mode of operation.

Abstract: A power supply circuit is proposed for supplying current to a pair of white LEDs connected in series. The circuit comprises a DC-DC power converter, with a charge pump coupled to the output of the DC-DC power converter. A super capacitor is coupled to the charge pump to be charged to a voltage on top of the converter output in a first mode of operation. The super capacitor is discharged through the pair of LEDs during a second mode of operation. A control stage is provided for switching between the first mode of operation and the second mode of operation.

Abstract: A feedback-controlled battery charger circuit (500) provides, alternatively, constant current and constant voltage to a battery (328) being charged. Current and voltage at the charger output (326) are sensed in sensing elements (308) and compared to preset reference values from reference generators for current (330) and voltage (332), thus generating error signals for both current and voltage. These error signals are amplified in separate amplifiers (530, 534); then, depending on battery voltage, one of the amplified error signals is automatically selected by a signal selector (540). The selected error signal is applied to a single compensation amplifier (554) with reactive feedback loop (552, 556); the output of the compensation amplifier with feedback (504) then controls the output current or voltage of the output stage (306). This output stage is a voltage controlled current source.