Abstract: A method and apparatus are disclosed for single-inductor multiple-output switching converter design. With the proposed freewheel switching control, this converter operates in a pseudo-continuous conduction mode (PCCM) and is capable of handling large load currents with a much smaller current ripple and peak inductor current, while retaining low cross regulation. It can also work in discontinuous conduction mode (DCM) for high efficiency at light loads. This design can be applied to have single or multiple outputs and for different types of DC-DC conversions.

Abstract: A pixel element for an image sensor comprising, a photodiode and a reset transistor connected to an input node, wherein said reset transistor is a PMOSFET connected between said input node and the supply voltage, and wherein said pixel further comprises parallel complementary signal paths.

Abstract: A three stage amplifier is disclosed provided with a novel frequency compensation technique. Only a single feedback loop with a single compensation capacitance is provided. Instead of a conventional nested compensation technique, damping factor control is provided by means of a fourth gain stage in order to stabilize the amplifier. The resulting amplifier is particularly useful to drive large capacitive loads for low-voltage low-power applications.

Abstract: A method and apparatus are disclosed for the dimming control of a fluorescent lamp driven by an electronic ballast. A small portion (eg less than 15°) of the phase of the input supply voltage is removed, and the precise amount of the phase removed is used to generate a switching signal that controls the switching frequency of the electronic ballast and hence the light power output. The switching frequency is generated by producing pulses of a width proportional to the amount of phase removed, integrating the pulses to produce a voltage proportional to the phase removed, converting that voltage to a current that varies with a frequency depending on the voltage, and using that varying current to generate the switching frequency.

Abstract: A nonlinear carrier controlled power factor correction circuit operates in the continuous and discontinuous conduction modes and provides unity power factor at the input of a power supply by only sensing the output voltage and the current flowing through a diode of a rectifier circuit. The power factor correction circuit monitors a level of current flowing through the diode and generates an integrated voltage signal representative of the level of current flowing through the diode. The integrated voltage signal is compared to a periodic, carrier waveform signal generated using a feedback signal corresponding to a level of an output voltage delivered to a load. A difference between the feedback signal and a reference signal determines the waveshape and characteristics of the carrier waveform. Preferably, leading edge modulation is used to control the duty cycle of a switch within the rectifier circuit.

Abstract: A technique for sensing current that employs an internal current sensing resistor. Two current sources of small and equal magnitude pull currents from two identical PNP transistors. Two PMOS transistors supply current to the PNP transistors. The PMOS transistors are scaled so the transistor on the output side of the circuit has an aspect ratio much greater than that of the transistor on the sensing side of the circuit. The result is that the currents through the PMOS transistors are proportional to each other and the current on the sensing side is much smaller than the current on the output side. The output current is the difference between the current through the PMOS transistor with the greater aspect ratio and the current through one of the small current sources. The sensing current, which passes through the internal sensing resistor, is the difference between the current flowing through the PMOS transistor with the lesser aspect ratio and the current flowing through the other small current source.