| Patent application number | Description | Published |
|---|
| 20080238397 | Circuit and method for soft start of a switching regulator from a residual voltage - For soft start of a switching regulator, the output voltage of the switching regulator is fed back to be compared with a ramp signal, in order to trigger a comparison signal when the ramp signal rises up to reach the feedback signal, to enable the switching regulator such that the output voltage changes from a residual voltage toward a target value. The low side switch of the switching regulator is kept off for a period of time after the switching regulator is enabled, so as to prevent a reverse current during the soft start period. | 10-02-2008 |
| 20090039704 | Simple circuit and method for improving current balance accuracy of a power converter system - A power converter system includes multiple converter modules connected to a share bus. Each of the converter modules mirrors the phase current of itself to provide a mirror current to the share bus, extracts an average current from the share bus, and compares the phase current of itself with the average current it extracts from the share bus to produce an output signal for modulation of the phase current of itself. Specifically, each of the converter modules is provided with a resistor connected to the share bus such that all the resistors are connected in parallel, and thus each of the resistors automatically receives an average current from the share bus. | 02-12-2009 |
| 20100320844 | POWER OFF DELAY CIRCUIT AND METHOD, AND AUDIO SYSTEM WITH POWER OFF DELAY - A power off delay circuit includes a switch connected between an external power input terminal and an internal power supply terminal, a capacitor connected to the internal power supply terminal, and a hysteresis comparator to switch the switch according to the voltages of the external power input terminal and the internal power supply terminal. During on-time of the switch, the external power input terminal is connected to the internal power supply terminal and the capacitor can be charged by the external power source. When the switch is off, the capacitor provides electric power for an internal circuit. Application of the power off delay circuit to an audio system may eliminate the turn-off pops of the audio system. | 12-23-2010 |
| 20100321849 | OVERSTRESS PROTECTION APPARATUS AND METHOD - An overstress protection apparatus includes a switch detector. The switch is arranged in a grounding path of a load system. The detector detects the current, voltage or temperature of the load system to determine a signal for controlling the switch, to thereby protect the load system working in normal conditions. | 12-23-2010 |
| 20110068761 | AVERAGE CURRENT REGULATOR AND DRIVER CIRCUIT THEREOF AND METHOD FOR REGULATING AVERAGE CURRENT - The present invention discloses an average current regulator, a driver circuit of an average current regulator, and a method for regulating an average current. The average current regulator includes: a power stage including at least one power transistor which switches according to a pulse width modulation (PWM) signal to convert an input voltage to an output current; a feedback circuit coupled to the power stage, for generating a feedback signal; an ON-time controller coupled to the feedback circuit, for receiving the feedback signal and generating an ON-time signal according to the feedback signal and an average reference signal relating to a target average current; and a PWM controller, for generating the PWM signal according to the ON-time signal to regulate the average of the output current to the target average current. | 03-24-2011 |
| 20110109238 | Digital dimming device and digital dimming method - The present invention discloses a digital dimming device and a digital dimming method, for controlling a plurality of light emitting device channels. The method comprises: generating a corresponding plurality of driving signals to control the plurality of light emitting device channels; receiving a PWM input signal having a duty ratio, and phase shifting the PWM input signal to generate multiple PWM output signals with about the same duty ratio as the PWM input signal, but with respectively shifted phases; and enabling or disabling corresponding driving signals by the multiple PWM output signals, respectively. | 05-12-2011 |
| 20110109290 | FREQUENCY CONTROL CIRCUIT AND METHOD FOR A NON-CONSTANT FREQUENCY VOLTAGE REGULATOR - A non-constant frequency voltage regulator includes a constant-time trigger to generate a pulse width modulation signal, a current generator to provide a first current to set a constant on-time or a constant off-time for the pulse width modulation signal, and a frequency control circuit to detect the pulse width of a phase node voltage, compare the pulse width with the constant on-time or the constant off-time set by the first current to generate a second current, and add the second current to the first current to supply to the constant-time trigger to control the frequency of the pulse width modulation signal. | 05-12-2011 |
| 20110109291 | FREQUENCY CONTROL CIRCUIT AND METHOD FOR A NON-CONSTANT FREQUENCY VOLTAGE REGULATOR - A non-constant frequency voltage regulator includes a constant-time trigger to trigger a constant on-time or a constant off-time for a pulse width modulation signal, a current generator to provide a first current to determine the constant on-time or the constant off-time, a power output stage operated by the pulse width modulation signal to produce a load current, and a frequency control circuit for loading feed forward by a second current added to the first current to adjust the constant on-time or the constant off-time for frequency compensation to the pulse width modulation signal. | 05-12-2011 |
| 20110109398 | FIXED-FREQUENCY CONTROL CIRCUIT AND METHOD FOR PULSE WIDTH MODULATION - A fixed-frequency control circuit and method detect the difference between the frequency of a pulse width modulation signal and a target frequency to adjust a current used to determine the on-time or off-time of the pulse width modulation signal, such that the frequency of the pulse width modulation signal is stable at the target frequency. | 05-12-2011 |
