| Patent application number | Description | Published |
| 20080218001 | METHOD AND APPARATUS FOR MODE SELECTION FOR HIGH VOLTAGE INTEGRATED CIRCUITS - A method is disclosed to add functionality to a terminal of a high voltage integrated circuit without the penalty of additional high voltage circuitry. The benefit is that alternative modes of operation can be selected for testing, trimming parameters of the integrated circuit, or any other purpose without the cost of an additional terminal. In one embodiment, ordinary low voltage circuitry monitors the voltage on the terminal that normally is exposed to high voltage. The configuration of a simple voltage detector and an ordinary latch allows easy entry into the test and trimming mode when the integrated circuit is not in the intended application, but prohibits entry into the test and trimming mode when the integrated circuit operates in the intended application. | 09-11-2008 |
| 20080218138 | METHOD AND APPARATUS FOR REDUCING AUDIO NOISE IN A SWITCHING REGULATOR - A switching regulator utilizing on/off control that reduces audio noise at light loads by adjusting the current limit of the switching regulator. In one embodiment, a switching regulator includes a state machine that adjusts the current limit of the switching regulator based on a pattern of feedback signal values from the output of the power supply for a preceding N cycles of the drive signal. The state machine adjusts the current limit lower at light loads such that cycles are not skipped to reduce the operating frequency of the switching regulator into the audio frequency range until the flux density through the transformer is sufficiently low to reduce the generation of audio noise. | 09-11-2008 |
| 20080259653 | METHOD AND APPARATUS FOR CONDITIONAL RESPONSE TO A FAULT CONDITION IN A SWITCHING POWER SUPPLY - Techniques are disclosed to regulate an output of a power converter. One example power converter controller circuit includes a line sense input to be coupled to receive a signal representative of an input voltage of a power converter. A feedback input to be coupled to receive a feedback signal representative of an output of the power converter is also included. A drive signal generator is also included to generate a drive signal coupled to control switching of a switch to provide a regulated output parameter at the output of the power converter in response to the feedback signal. The drive signal generator is coupled to receive a plurality of inputs including the line sense input and the feedback input. The drive signal generator is coupled to latch the power converter into an off state in response to a detection of a fault condition in the power converter as detected by the plurality of inputs if the power converter input voltage is above a first threshold level. The drive signal generator to be unresponsive to the signal representative of the power converter input voltage while the controller is regulating the output parameter at the output of the power converter. | 10-23-2008 |
| 20090021298 | METHOD AND APPARATUS TO SELECT A PARAMETER/MODE BASED ON A TIME MEASUREMENT - Techniques are disclosed to select functional parameters and/or operating modes of a circuit based on a time measurement are disclosed. One example integrated circuit includes a threshold detection and timing circuit that is coupled to measure a signal during an initialization period of the integrated circuit from a multifunction capacitor that is to be coupled to a first terminal of the integrated circuit. A selection circuit is coupled to the threshold detection and timing circuit to select a parameter/mode of the integrated circuit in response to the measured signal from the multifunction capacitor during the initialization period of the integrated circuit. The multifunction capacitor is coupled to provide an additional function for the integrated circuit after the initialization period of the integrated circuit is complete. | 01-22-2009 |
| 20090040795 | METHOD AND APPARATUS FOR INCREASING THE POWER CAPABILITY OF A POWER SUPPLY - Techniques are disclosed to extend an on time period of switch to regulate a transfer of energy from an input of a power supply to an output of a power supply. One example integrated circuit includes an energy transfer element coupled between an input and an output of the power supply. A switch is coupled to the input of the energy transfer element. A controller is coupled to the switch to control switching of the switch to regulate a transfer of energy from the input of the power supply to the output of the power supply in response to a feedback signal received from the output of the power supply. The controller is coupled to limit a maximum on time period of the switch a first maximum on time period in response to a first range of power supply operating conditions and to a second maximum on time period for a second range of power supply operating conditions. | 02-12-2009 |
| 20090189682 | METHOD AND APPARATUS FOR MODE SELECTION FOR HIGH VOLTAGE INTEGRATED CIRCUITS - A method is disclosed to add functionality to a terminal of a high voltage integrated circuit without the penalty of additional high voltage circuitry. The benefit is that alternative modes of operation can be selected for testing, trimming parameters of the integrated circuit, or any other purpose without the cost of an additional terminal. In one embodiment, ordinary low voltage circuitry monitors the voltage on the terminal that normally is exposed to high voltage. The configuration of a simple voltage detector and an ordinary latch allows easy entry into the test and trimming mode when the integrated circuit is not in the intended application, but prohibits entry into the test and trimming mode when the integrated circuit operates in the intended application. | 07-30-2009 |
| 20090195229 | METHOD AND APPARATUS FOR REDUCING AUDIO NOISE IN A SWITCHING REGULATOR - A switching regulator utilizing on/off control that reduces audio noise at light loads by adjusting the current limit of the switching regulator. In one embodiment, a switching regulator includes a state machine that adjusts the current limit of the switching regulator based on a pattern of feedback signal values from the output of the power supply for a preceding N cycles of the drive signal. The state machine adjusts the current limit lower at light loads such that cycles are not skipped to reduce the operating frequency of the switching regulator into the audio frequency range until the flux density through the transformer is sufficiently low to reduce the generation of audio noise. | 08-06-2009 |
| 20090251931 | METHOD AND APPARATUS FOR CONDITIONAL RESPONSE TO A FAULT CONDITION IN A SWITCHING POWER SUPPLY - Techniques are disclosed to regulate an output of a power converter. One example power converter controller circuit includes a line sense input to be coupled to receive a signal representative of an input voltage of a power converter. A feedback input to be coupled to receive a feedback signal representative of an output of the power converter is also included. A drive signal generator is also included to generate a drive signal coupled to control switching of a switch to provide a regulated output parameter at the output of the power converter in response to the feedback signal. The drive signal generator is coupled to receive a plurality of inputs including the line sense input and the feedback input. The drive signal generator is coupled to latch the power converter into an off state in response to a detection of a fault condition in the power converter as detected by the plurality of inputs if the power converter input voltage is above a first threshold level. The drive signal generator to be unresponsive to the signal representative of the power converter input voltage while the controller is regulating the output parameter at the output of the power converter. | 10-08-2009 |
| 20090256544 | METHOD AND APPARATUS TO LIMIT OUTPUT POWER IN A SWITCHING POWER SUPPLY - Techniques are disclosed to adjust a current limit in a switching regulator. One example switching regulator includes a comparator having first and second inputs and an output. The first input of the comparator is adapted to sense a current flow through a switch and the second input of the comparator is adapted to sense a variable current limit value. A controller is coupled to the output of the comparator and to the switch to control switching of the switch to regulate an output of a power supply in response a feedback signal. The controller disables the switch if the sensed current flow through the switch is greater than the sensed variable current limit value. The variable current limit value is set to a first variable current limit value by the controller in response to an input line voltage of the power supply if there is not an over current condition during a first switching cycle that occurs after a skipped switching cycle of the switch. The variable current limit value is set to a second variable current limit value by the controller in response to the input line voltage if there is the over current condition during the first switching cycle that occurs after the skipped switching cycle. | 10-15-2009 |
| 20090303766 | METHOD AND APPARATUS FOR INCREASING THE POWER CAPABILITY OF A POWER SUPPLY - Techniques are disclosed to extend an on time period of switch to regulate a transfer of energy from an input of a power supply to an output of a power supply. One example integrated circuit includes an energy transfer element coupled between an input and an output of the power supply. A switch is coupled to the input of the energy transfer element. A controller is coupled to the switch to control switching of the switch to regulate a transfer of energy from the input of the power supply to the output of the power supply in response to a feedback signal received from the output of the power supply. The controller is coupled to limit a maximum on time period of the switch a first maximum on time period in response to a first range of power supply operating conditions and to a second maximum on time period for a second range of power supply operating conditions. | 12-10-2009 |
| 20100033147 | METHOD AND APPARATUS FOR MAINTAINING A CONSTANT LOAD CURRENT WITH LINE VOLTAGE IN A SWITCH MODE POWER SUPPLY - A power supply regulator including a variable current limit threshold that increases during an on time of a switch. In one aspect, a power supply regulator includes a comparator that has a first input coupled to sense a voltage representative of a current flowing through a switch during an on time of the switch. The comparator has a second input coupled to receive a variable current limit threshold that increases during the on time of the switch. A feedback circuit is coupled to receive a feedback signal representative of an output voltage at an output of a power supply. A control circuit is coupled to generate a control signal in response to an output of the comparator and in response to an output of the feedback circuit. The control signal is to be coupled to a control terminal of the switch to control switching of the switch. | 02-11-2010 |
| 20100073041 | METHOD AND APPARATUS TO SELECT A PARAMETER/MODE BASED ON A MEASUREMENT DURING AN INITIALIZATION PERIOD - Techniques are disclosed to select functional parameters and/or operating modes of a circuit based on a measurement during an initialization period. In one aspect an integrated circuit includes a threshold detection circuit coupled to measure during an initialization period of the integrated circuit a signal from a first external circuit comprising one or more components coupled to a first external terminal of the integrated circuit. A selection circuit is coupled to the threshold detection circuit to select a parameter/mode of the integrated circuit in response to the signal from the first external circuit during the initialization period of the integrated circuit. The first external terminal is further coupled to one or more additional external circuits, each of which comprising one or more components. The one or more additional external circuits are coupled to provide one or more signals at the first external terminal to be used by the integrated circuit during normal operation at times other than the initialization period to provide at least one additional function for the integrated circuit after the initialization period of the integrated circuit is complete. | 03-25-2010 |
| 20100246222 | METHOD AND APPARATUS FOR DIGITAL CONTROL OF A SWITCHING REGULATOR - Various techniques directed to the digital control of a switching regulator are disclosed. In one aspect, a power supply regulator includes a compare circuit to be coupled to receive a feedback signal representative of an output level of a power supply. This causes a feedback state signal to be generated having a first feedback state that represents an output level of the power supply that is above a threshold level and a second feedback state that represents an output level of the power supply that is below the threshold level. An adjustment circuit is coupled to the compare circuit to adjust the feedback state signal in response to at least one of adjusting the threshold level or adjusting the feedback signal. The adjustment to the feedback state signal tends to cause the feedback state signal to revert from a state at the time of adjustment to a state immediately preceding the adjustment. A control circuit is to be coupled to a power switch and is to be coupled to receive an oscillating signal and the feedback state signal. The control circuit is to control switching of the power switch in response to the oscillating signal and the feedback state signal to regulate the output level of the power supply. | 09-30-2010 |
| 20100321039 | METHOD AND APPARATUS TO SELECT A PARAMETER/MODE BASED ON A TIME MEASUREMENT - An example integrated control circuit includes a regulator, a first comparator, a second comparator, and a counter. The regulator is to charge, during a time period, a capacitor. The first comparator is to provide an output indicating when a voltage on the capacitor reaches a first threshold voltage. The second comparator is coupled to provide an output indicating when the voltage on the capacitor reaches a second threshold voltage. The counter is coupled to begin counting in response to the first threshold voltage being reached and is coupled to stop counting in response to the second threshold voltage being reached. The counter is coupled to provide an output representative of the capacitance value of the capacitor during the time period and the integrated control circuit receives a bias current at the terminal from the capacitor to provide power to operate the integrated control circuit after the time period has ended. | 12-23-2010 |
| 20110019441 | METHOD AND APPARATUS FOR DIGITAL CONTROL OF A SWITCHING REGULATOR - In one aspect, a power supply regulator includes a feedback terminal, a node, a control circuit, a first current source, and a second current source. The node is coupled to the feedback terminal to provide a feedback state signal in response to a feedback current through the feedback terminal. The feedback state signal has feedback states that represent an output of the power supply. The control circuit is to be coupled to a power switch and to receive the feedback state signal to regulate the output of the power supply. The first current source is coupled to the node to provide a first current to the node. The second current source is coupled to the node to selectively remove a second current from the node to modulate the feedback current and to alter the feedback state of the feedback state signal. | 01-27-2011 |
| 20110025288 | METHOD AND APPARATUS FOR MAINTAINING A CONSTANT LOAD CURRENT WITH LINE VOLTAGE IN A SWITCH MODE POWER SUPPLY - A power supply regulator including a variable current limit threshold that increases during an on time of a switch. In one aspect, a power supply regulator includes a comparator coupled to receive a signal representative of a current through a switch during an on time of the switch. The comparator is further coupled to receive a variable current limit threshold that increases during the on time of the switch. The power supply regulator also includes a feedback circuit coupled to receive a feedback signal representative of an output of a power supply. A control circuit is also included and is coupled to the switch, to an output of the comparator, and to an output of the feedback circuit. The control circuit is coupled to control a switching of the switch in response the output of the comparator and the output of the feedback circuit to regulate the output of the power supply. | 02-03-2011 |