Abstract: An embodiment of the present invention discloses a voltage amplifier circuit which includes a signal generator, a mixer and an amplifier. The signal generator is arranged to generate an input signal; the mixer is arranged to mix the input signal with an analog signal to generate an intermediate input signal having a first voltage range; and the amplifier is arranged to convert the intermediate input signal into an output signal having a second voltage range in a Rail-to-Rail manner, wherein the second voltage range is larger than the first voltage range.

Abstract: A switch control circuit has a voltage sensing function. The switch control circuit includes a voltage-clamping buffer, a set driver, a reset driver, and an R-dominant SR latch. The voltage-clamping buffer shifts a switch voltage to generate a down-shifted switch voltage. The set driver generates a set signal according to the down-shifted switch voltage. The reset driver generates a reset signal according to the down-shifted switch voltage. The R-dominant SR latch comprises a set end for receiving the set signal, a reset end for receiving the reset signal, an output end for outputting a switch control signal for controlling conductance of a first transistor coupled to a primary winding of a transformer, and an output bar end for outputting an inverted switch control signal.

Abstract: A floating protection circuit is utilized for a photo-flash capacitor charger. The floating protection circuit includes a comparator and a timer. The comparator is coupled between two feedback resistors of the photo-flash capacitor charger for receiving a feedback voltage. When the feedback voltage is lower than an offset voltage, the comparator outputs a reset signal. If the timer does not receive the reset signal for a predetermined time, the timer outputs a turn-off signal to a switch control circuit of the photo-flash capacitor charger to shut down the switch control circuit.

Abstract: A voltage level shifter with voltage boost mechanism is disclosed for interfacing two circuit units having different operating voltage swings. The voltage level shifter includes a first inverter, a second inverter, a first capacitor, a second capacitor and a plurality of transistors. The input and power ends of the first inverter function to receive an input voltage and a first voltage respectively. The output end of the second inverter functions to provide an output voltage. When the input voltage is a ground voltage, the output voltage is also a ground voltage; meanwhile, the switches are controlled for charging the first and second capacitors to a second voltage and a third voltage respectively. When the input voltage is the first voltage, a sum voltage of the first, second, and third voltages is furnished to the power end of the second inverter for providing the sum voltage as the output voltage.

Abstract: A voltage level shifter with voltage boost mechanism is disclosed for interfacing two circuit units having different operating voltage swings. The voltage level shifter includes a first inverter, a second inverter, a first capacitor, a second capacitor and a plurality of transistors. The input and power ends of the first inverter function to receive an input voltage and a first voltage respectively. The output end of the second inverter functions to provide an output voltage. When the input voltage is a ground voltage, the output voltage is also a ground voltage; meanwhile, the switches are controlled for charging the first and second capacitors to a second voltage and a third voltage respectively. When the input voltage is the first voltage, a sum voltage of the first, second, and third voltages is furnished to the power end of the second inverter for providing the sum voltage as the output voltage.

Abstract: The power transistor circuit with high-voltage endurance includes a first power transistor, a second power transistor and an enabling circuit. The first power transistor includes a first voltage endurance and a first inner resistance, while the second power transistor includes a second voltage endurance and a second inner resistance. The first voltage endurance and the first inner resistance are smaller than the second voltage endurance and the second inner resistance, respectively. The drain of the second power transistor is connected to the drain of the first power transistor and the enabling circuit. The enabling circuit enables the second power transistor first, and when the drain voltage of the first power transistor is smaller than the first endurance, the enabling circuit then enables the first power transistor.

Abstract: The power transistor circuit with high-voltage endurance includes a first power transistor, a second power transistor and an enabling circuit. The first power transistor includes a first voltage endurance and a first inner resistance, while the second power transistor includes a second voltage endurance and a second inner resistance. The first voltage endurance and the first inner resistance are smaller than the second voltage endurance and the second inner resistance, respectively. The drain of the second power transistor is connected to the drain of the first power transistor and the enabling circuit. The enabling circuit enables the second power transistor first, and when the drain voltage of the first power transistor is smaller than the first endurance, the enabling circuit then enables the first power transistor.