11167 results about "Voltage regulator" patented technology

A current-mode switching regulator uses adaptive current sensing to reliably monitor an inductor current in a cost-efficient and power-efficient manner. A semiconductor switch periodically turns on to conduct the inductor current. A voltage drop across the semiconductor switch is monitored when the semiconductor switch is on. A variable gain amplifier with an automatic gain control loop generates a feedback signal from the voltage drop of the semiconductor switch when conducting to provide an indication of the inductor current to a controller. The automatic gain control loop compensates for any variations in the on-resistance of the semiconductor switch.

A buck-boost switching regulator includes two buck switches and two boost switches. Two ramp voltages VY and VY are generated. The voltage VY is compared to a voltage VEA1 that is proportional to the output of the switching regulator. This defines the duty cycle of the two buck switches. The voltage VX is compared to a voltage VEA2 that is inversely proportional to the output of the switching regulator. This defines the duty cycle of the two boost switches. The regulator seamlessly transitions between Buck, Boost and Buck-Boost modes depending on input and output conditions.

An N-phase switching voltage regulator includes N current sensing elements which carry respective phase currents. The voltages present at the switch node sides of the sensing elements are summed and presented to an amplifier which also receives the regulator's output voltage, to produce an output which is proportional to the regulator's total output current I_out. The invention also provides a means for direct insertion of total inductor output current information into a regulator's voltage-mode control loop, to provide active voltage positioning (AVP) for the output voltage. A voltage based on total inductor output current is summed with the regulator's reference voltage; this sum and V_out are applied to the voltage control error amplifier, the output of which is processed to operate the regulator's switches. This enables the regulator's output to have a desired droop impedance and to provide AVP of V_out as a function of total filtered inductor output current I_out(fltr).

A supply voltage controlled power amplifier that comprises a power amplifier, a closed power control feedback loop configured to generate a power control signal, and a dual voltage regulator coupled to the power control feedback loop, the dual voltage regulator comprising a first regulator stage and a second regulator stage, wherein the closed power control loop minimizes noise generated by the first regulator stage.

A switching voltage regulator is disclosed for regulating a voltage supplied to system circuitry. The switching voltage regulator comprises an oscillator operable to generate an oscillator signal representing a gate speed of a reference circuit in the system circuitry, and a frequency generator operable to generate a reference signal representing a target gate speed of the reference circuit. A cycle comparator compares at least one cycle of the oscillator signal to at least one cycle of the reference signal, and switching circuitry charges a charging element based at least on part on the comparison.

Methods and apparatus are disclosed for efficient switching regulators that adapt automatically to, and operate with, input voltages that are above, below, or equal to the output voltage. The disclosed switching regulators demonstrate advantages of both buck and boost converters at high efficiency.

LED driver circuits containing voltage reducing devices, voltage regulating devices, and voltage converting devices are disclosed as the main components to provide power to LEDs. The LED driver circuits are designed to work with a ballast, mains alternating current voltage, direct current voltage, and electromagnetic induction power. The voltage regulating devices can be a resistor in series with at least one zener diode or a voltage regulator both in parallel with and providing power to the LEDs. The LEDs can also be anti-parallel diode pairs consisting of one diode and one LED or two LEDs, or the LEDs can be anti-parallel diode string pairs consisting of diodes and LEDs or all LEDs. The LED driver circuits will be incorporated into LED replacement lamps, and in particular to LED lamps to replace fluorescent lamps for use with existing ballasts and other power sources where the ballast may be removed or bypassed.

Voltage regulators often have coupled output inductors because coupled output inductors provide improvements in cost and efficiency. Coupled inductors are often used in multi-phase voltage regulators. Feedback control of voltage regulators often requires accurate and responsive sensing of output current. Provided is a technique for accurately sensing the magnitude of output current in coupled inductors. An RC circuit (comprising a resistor and capacitor in series) is connected in parallel with the coupled inductor. The inductor has a leakage inductance Lk and a DC (ohmic) resistance of DCR. The resistor and capacitor are selected such that an RC time constant is equal to an L/R time constant of Lk/DCR. With the matching time constants, a sum of voltages on the capacitors is accurately proportional to a sum of currents flowing in the output inductors. Also provided is a technique for sensing current when an uncoupled center tap inductor is present.

A method and apparatus for adaptively adjusting the operating voltage of an integrated circuit in response to tester-to-system variations, worst-case testing techniques, process variations, temperature variations, or reliability wearout mechanisms. The minimum operating voltage of an integrated circuit is determined either during external testing of the integrated circuit or during built-in-self-testing. The minimum operating voltage is transmitted to a variable voltage regulator where it is used to set the output of the regulator. The output of the regulator supplies the integrated circuit with its operating voltage. This technique enables tailoring of the operating voltage of integrated circuits on a part-by-part basis which results in power consumption optimization by adapting operating voltage in response to tester-to-system variations, worst-case testing techniques, process variations, temperature variations or reliability wearout mechanisms. Alternatively, the invention enables adaptive adjustment of the operating frequency of an integrated circuit. The invention enables system designers to adaptively optimize either system performance or power consumption on a part-by-part basis in response to tester-to-system variations, worst-case testing techniques, process variations, temperature variations or reliability wearout mechanisms.

Disclosed is a power regulator for providing precisely regulated power to a microelectronic device such as a microprocessor. Improved power regulation is accomplished by optimizing the power efficiency of the power regulator. In particular, in a multiphase system, the number of active phases is increased or decreased to achieve optimum power efficiency. The multiphase voltage regulator adapts the operating mode to maximize efficiency as the load current demand of the load device changes by adjusting the number of active phases to maximize efficiency. The total value of current provided by the regulator and the total number of active phases is determined, the total number of active phases is compared with the number of active phases required to provide the total value of current at maximum efficiency; and the number of active phases is adjusted to provide the total value of current at maximum efficiency. A current sense circuit senses the current at each phase, a summing circuit coupled to the output of the current sense circuit provides the total current value of all the measured phases, a circuit coupled to the output of the summing circuit provides the time averaged total current value to a threshold detecting circuit that determines the number of phases at which the voltage regulator should be operating for maximum efficiency, and a circuit for comparing the number of phases that are operating to the number of phases at which the voltage regulator should be operating adjusts the number of active phases to the number of phases at which the voltage regulator should be operating for maximum efficiency.