Patent application number | Description | Published |
20090179583 | DIGITALLY SYNCHRONIZED INTEGRATOR FOR NOISE REJECTION IN SYSTEM USING PWM DIMMING SIGNALS TO CONTROL BRIGHTNESS OF COLD CATHODE FLUORESCENT LAMP FOR BACKLIGHTING LIQUID CRYSTAL DISPLAY - An apparatus and method for controlling the operation of a utility device, such as a cold cathode fluorescent lamp that is powered in accordance with a pulse width modulation (PWM) signal, includes an analog sensor which monitors the utility device to derive an output signal representative of the PWM signal. An integrating analog-to-digital converter (ADC), which is coupled to the sensor and has its operation synchronized with an integral multiple of the period of the PWM signal, produces an output representative of an average of the output of the utility device. | 07-16-2009 |
20100052611 | SWITCHING REGULATOR INPUT CURRENT SENSING CIRCUIT, SYSTEM, AND METHOD - A Buck switching regulator includes first Buck switching regulator circuitry is operable to generate a first output voltage from an input voltage and operable to generate a first sensed voltage having a value that is proportional to an output current being provided by the first Buck switching regulator circuitry. The first Buck switching regulator circuitry receives an input current and operates at a first duty cycle determined by a duty cycle signal. Input current sensing circuitry includes second Buck switching regulator circuitry coupled to the first Buck regulator switching circuitry to receive the duty cycle signal and to receive the first sensed voltage as an input voltage to the second Buck switching regulator circuitry. The second Buck switching regulator circuitry is operable responsive to the duty cycle signal to generate a second output voltage from the first sensed voltage. The second output voltage has a value that is proportional to the input current being supplied to the first Buck switching regulator circuitry. Such a Buck switching regulator can be utilized in a variety of different types of electronic systems, such as laptop computer systems, and can also be used in charging systems in laptop computer and other types of electronic systems. | 03-04-2010 |
20150035504 | SWITCHING REGULATOR INPUT CURRENT SENSING CIRCUIT, SYSTEM, AND METHOD - A Buck switching regulator includes first Buck switching regulator circuitry is operable to generate a first output voltage from an input voltage and operable to generate a first sensed voltage having a value that is proportional to an output current being provided by the first Buck switching regulator circuitry. The first Buck switching regulator circuitry receives an input current and operates at a first duty cycle determined by a duty cycle signal. Input current sensing circuitry includes second Buck switching regulator circuitry coupled to the first Buck regulator switching circuitry to receive the duty cycle signal and to receive the first sensed voltage as an input voltage to the second Buck switching regulator circuitry. The second Buck switching regulator circuitry is operable responsive to the duty cycle signal to generate a second output voltage from the first sensed voltage. The second output voltage has a value that is proportional to the input current being supplied to the first Buck switching regulator circuitry. Such a Buck switching regulator can be utilized in a variety of different types of electronic systems, such as laptop computer systems, and can also be used in charging systems in laptop computer and other types of electronic systems. | 02-05-2015 |