Dynamically-compensated controller
Granted: March 27, 2012
Patent Number:
8143871
A dynamically-compensated controller may generate a switching signal for a DC power supply. The controller may include a feedback circuit having a first analog-to-digital converter and a separate analyzer circuit for generating information indicative of performance characteristics of the feedback circuit based on information about the results of a test perturbation signal at an output of the DC power supply. The analyzer circuit may include a DC removal circuit configured to…
Over-voltage protection circuit
Granted: March 20, 2012
Patent Number:
8139329
An over-voltage protection circuit for use in low power integrated circuits is provided. The over-voltage protection circuit distributes certain connection and conditioning circuitry to a component network external to the integrated circuit. As a result, the integrated circuit need not be created with specialized high voltage components, significantly reducing its cost and complexity, and allowing it to be used in a wider range of end-user applications.
A/D converter using isolation switches
Granted: March 6, 2012
Patent Number:
8130133
In an A/D converter, isolation switches are used between the capacitors and the conversion switches. The conversion switches are those switches used to selectively couple the plates of the binary weighted capacitors to either Vref or 0 volts during the A/D conversion process. During sampling of the input voltage signal, the isolation switches are opened to isolate the conversion switches from the wide range of possible input voltages at the bottom plates of the capacitors. Therefore, the…
Amplitude lock loop for producing constant amplitude oscillator ramp signal
Granted: February 21, 2012
Patent Number:
8120330
An oscillator that includes an energy storage system configured to store energy, a ramp circuit configured to generate an oscillating ramp signal having a slope that is a function of the amount of energy stored in the energy storage system, a charge circuit configured to controllably deliver energy into or remove energy from the energy storage system, a comparator circuit configured to compare the oscillating ramp signal with a reference signal; and/or a charge control circuit configured…
Average inductor current mode switching converters
Granted: February 21, 2012
Patent Number:
8120335
An average current mode switching converter is described for providing a regulated output current independent of load conditions, and a regulated output voltage as a function of the load connected to the converter. The converter includes an inductor, a modulator, a feedback loop, and a precharger. The modulator is configured to provide a regulated current through the inductor The feed back loop is coupled between the inductor and the modulator for regulating the current through the…
Circuitry and methodology for protecting a boost DC/DC converter
Granted: February 14, 2012
Patent Number:
8116045
Protection circuitry protects a boost converter coupled between input and output nodes for driving a load coupled to the output node. The protection circuitry may comprise a first circuit configured for monitoring a voltage at the output node, the voltage being caused by a signal having a voltage proximate to, or lower than, an input voltage of the boost converter. The protection circuitry may also include a second circuit configured for coupling together the input node with respect to…
Linearity in LED dimmer control
Granted: January 3, 2012
Patent Number:
8089216
A flyback controller may generate a switching signal for controlling the delivery of input current into a primary winding of a transformer in a flyback converter that has a secondary winding in the transformer and that is driven by AC output from a dimmer control that is chopped at a phase angle based on a setting of the dimmer control. The flyback controller may include a tracking input configured to receive a dimmer output tracking signal that is representative of the instantaneous…
Bandgap voltage and current reference
Granted: December 27, 2011
Patent Number:
8085029
Circuits and methods that improve the performance of reference circuits are provided. A reference generator circuit maintains a substantially constant output current over an extended temperature for use as a reference. Output current fluctuations caused by a poorly specified power source or process variations are minimized or eliminated.
Lead plating technique for singulated IC packages
Granted: December 13, 2011
Patent Number:
8076181
A packaging technique is described for QFNs, DFN, and other surface mount packages that allows the sides of leads to be plated with a wettable metal prior to the lead frames being singulated from the lead frame sheet. The leads of the lead frames in the sheet are shorted together and to the body of the lead frame sheet by a sacrificial interconnect structure. Chips are mounted to the lead frames and encapsulated, leaving the bottoms of the leads exposed. The lead frame sheet is then…
Magnetic isolation of power sourcing equipment control circuitry
Granted: December 13, 2011
Patent Number:
8076793
A circuit for providing electrical isolation of Power Sourcing Equipment (PSE) circuitry from external circuitry in a Power over Ethernet (PoE) system has an inductive circuit for providing an isolation barrier to electrically isolate an isolated side of the isolation circuit from a non-isolated side of the isolation circuit. A signal path circuitry is configured for transferring bidirectional and/or unidirectional signals over the isolation barrier between respective nodes at the…
Synchronous rectifier control for synchronous boost converter
Granted: November 22, 2011
Patent Number:
8063615
A synchronous boost DC/DC conversion system comprises an input for receiving a DC input voltage, an output for producing a DC output voltage, a power switch controllable to adjust an output signal of the conversion system, and an inductor coupled to the input. A synchronous rectifier is configurable to create a conduction path between the inductor and the output to provide the inductor discharge. A control circuit is provided for controlling the synchronous rectifier as the input voltage…
Method and system for high efficiency, fast transient multi-channel LED driver
Granted: November 15, 2011
Patent Number:
8058810
System and method for a light emitting diode (LED) driver are disclosed. To supply an LED bus voltage to a large array of LEDs organized in multiple channels where one or more LEDs are connected in series in each channel, an LED driver includes a power converter, a feedback generation circuit, and a phase-division based controller. The power converter is configured for providing the LED bus voltage to the multiple LED channels based on a voltage control signal. The feedback generation…
Buck-mode boost converter with regulated output current
Granted: November 15, 2011
Patent Number:
8058812
An LED driver circuit that includes a buck-mode boost converter that provides a regulated output current and that requires only a single connection to each channel of LEDs. The buck-mode boost controller may include a current regulator that includes an integrator. The current regulator may be configured to integrate a difference between a reference signal that is representative of the desired level of the average current through the electronic power switch and a detected signal that is…
Enhancing an operational amplifier's capacitive load driving capability using parallel Miller feedback
Granted: November 15, 2011
Patent Number:
8058931
An apparatus for an improved operational amplifier. The disclosed improved operational amplifier comprises an operational amplifier, a first feedback circuit, and one or more secondary feedback circuits. The operational amplifier include a plurality of serially coupled gain stages and is configured so that an output of each gain stage drives an input of a next gain stage and an output of a last gain stage drives a load external to the improved operational amplifier. The first feedback…
Power measurement circuit
Granted: November 1, 2011
Patent Number:
8049487
A power measurement circuit and method are described. The circuit comprises: a transconductance rectifier arrangement including an input and configured to receive a periodically varying input voltage signal having an approximate 50% duty cycle; and an averaging filter for producing a time averaged DC output signal proportional to the mean square of the voltage at the input of the transconductance rectifier arrangement and representative of the average power of the input voltage signal…
Accelerated response to load transients in PFM DC-to-DC converters
Granted: October 4, 2011
Patent Number:
8030907
A pulse generator circuit in a DC-to-DC converter may be configured to generate pulses that have a frequency that increases in response to increases in the load on the DC-to-DC converter. The pulse generator circuit may be configured to cause each pulse to have a constant width. When the pulse reaches the end of the constant width and the magnitude of the current through an inductance in the converter is less than a threshold value, however, the pulse generator may be configured to…
Systems and methods for fast switch turn on approximating ideal diode function
Granted: September 20, 2011
Patent Number:
8022679
A switching circuit approximating the fast switching characteristics and small forward voltage drop of an ideal diode is provided. The switching circuit may include a voltage multiplier circuit, a reservoir capacitor and a pull up switch configured to be coupled to the control terminal of a semiconductor switch.
Laser process for side plating of terminals
Granted: September 13, 2011
Patent Number:
8017447
A method of preparing a portion of the side of a terminal of an Integrated Circuit (IC) package for solder is disclosed. The method comprises the steps of attaching an IC die to a leadframe comprising a connecting bar, reducing the thickness of a portion of the connecting bar, overmolding the leadframe with a mold compound, removing the mold compound from the reduced-thickness portion of the connecting bar using a laser, coating the reduced-thickness portion of the connecting bar with a…
Time-multiplexed residue amplifier
Granted: September 13, 2011
Patent Number:
8018370
A system is configured and a method is provided for receiving an input ratio represented by a first input signal and a second input signal, and producing an output ratio represented by a first output signal and a second output signal. The system is constructed and the method is provided for alternately operating in at least two time periods, wherein in one time period the first input signal, a low accuracy amplifier, and the first output signal are selectively coupled, and in another…
Dimmer control leakage pull down using main power device in flyback converter
Granted: September 6, 2011
Patent Number:
8013544
A flyback controller may receive a chopped and rectified AC voltage from a dimmer control, each cycle of which may have a controllable off period that is substantially attenuated but not always zero due to leakage of the dimmer control, and a controllable on period that substantially tracks the AC voltage. The flyback controller may include a control circuit configured to generate a switching signal based on the signal from the dimmer input. The switching signal may controllably…
