| PacificTech Microelectronics, Inc. Patent applications |
| Patent application number | Title | Published |
|---|
| 20120001683 | VOLTAGE LEVEL SHIFT CIRCUITS AND METHODS - In one embodiment, the present invention includes a charge pump circuit. The charge pump circuit comprises a plurality of terminals, a plurality of switches for selectively coupling the plurality of terminals, and a control circuit. A first input terminal receives a first reference voltage and a second input terminal receives a second reference voltage. First, second, third, and fourth flying capacitor terminals and the first and second input terminals are selectively coupled together in different configurations. The control circuit selects the switches to actuate according to a cycling of at least three phases of configuration. The cycling shifts the first and second reference voltages to provide dual power supply rails. | 01-05-2012 |
| 20100232628 | Circuits and Methods for Reducing Pop Noise in Class D Amplifiers - In one embodiment the present invention includes a method for starting up a class D amplifier. The method comprises increasing, gating, and driving. The increasing includes increasing a duty cycle of a pulse train from a first duty cycle to a second duty cycle. The gating includes gating a signal based on the increasing of the duty cycle. The gating results in a gated signal. The driving includes driving an output signal from the gated signal to charge an output capacitor. The output capacitor is coupled to a speaker. The increasing of the duty cycle contributes to the charging of the output capacitor such that switching sounds detectable by the human ear are reduced. | 09-16-2010 |
| 20080303493 | Boost regulator startup circuits and methods - Embodiments of the present invention include a method of starting a boost regulator comprising during an initial phase beginning when the boost regulator is powered off, coupling a first current from the input node to the output node to increase a voltage on the capacitor to a first voltage level, during a second phase following the first phase, switching the PMOS transistor and the NMOS transistor, during a third phase following the second phase, turning said PMOS off and switching said NMOS transistor, and during a fourth phase, synchronously switching the PMOS transistor and NMOS transistor. | 12-11-2008 |
| 20080272651 | LED current control circuits and methods - Embodiments of the present invention include circuits and methods for electrical current control. In one embodiment, a regulator provides power to the anode end of a set of LED strings. A current setting circuit derives its current from a current reference and generates multiple matching currents that drive the low side (cathode end) of the set of LED strings. The current setting circuit also contains a feedback signal to the regulator that helps maintain a desired voltage level to the anode end of the LED strings. This embodiment is designed to be expandable and drive any number of LED strings. The present invention may be implemented with a high or low side driver scheme to drive the current. Also, the present invention may be implemented with bipolar, nmos, pmos, or any device that operates as a transistor. | 11-06-2008 |
| 20080209250 | Single wire communication circuits and methods - Embodiments of the present invention include systems and methods of control using a single wire. The systems and methods presented allow sending or receiving commands and data through a single wire. In one embodiment, commands and data are received by the control system through a single terminal. In another embodiment, commands and data are received and transmitted from the control system through a single terminal. | 08-28-2008 |
