Synchronous rectifier control for synchronous boost converter
Granted: November 13, 2012
Patent Number:
8310216
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…
Current ripple reduction circuit for LEDs
Granted: November 13, 2012
Patent Number:
8310172
A powered LED circuit may include a power supply configured to generate and deliver an output current at a controllable average value with a substantial ripple component, one or more LEDs connected together, and a ripple reduction circuit connected to the power supply and to the one or more LEDs. The ripple reduction circuit may have a current regulator connected in series with the one or more LEDs which is configured to substantially reduce fluctuations in the current which flows…
Third order intermodulation cancellation by in-line generated signal
Granted: November 6, 2012
Patent Number:
8305142
An actual linear amplifier distorts an input signal, such as an RF signal, and generates third order intermodulation (IM3) products. A single-port predistortion circuit is connected at a single node of an input line to the amplifier via an AC coupling capacitor. The fundamental frequency of the input signal is applied to a forward biased diode junction. The current through the diode is applied to a second capacitor. The appropriate setting of a tuning device, such as a tunable resistor…
Bias point setting for third order linearity optimization of class A amplifier
Granted: November 6, 2012
Patent Number:
8305148
An actual linear amplifier distorts an input signal, such as an RF signal, and generates third order intermodulation (IM3) products. In an embodiment of a Class A amplifier, the linear amplifier is a bipolar, common emitter-configured (CE) transistor using a cascode transistor to provide a fixed collector bias voltage to the CE transistor. The CE transistor has a transconductance vs. base-emitter voltage (VBE) characteristic which, when plotted, shows a transconductance that increases…
Efficiency measuring circuit for DC-DC converter which calculates internal resistance of switching inductor based on duty cycle
Granted: October 2, 2012
Patent Number:
8278895
An efficiency measuring circuit may measure the efficiency of a DC-DC converter having a switching inductor with an internal DC resistance and a plurality of electronic switches that control current through the inductor. A duty cycle circuit may measure the duty cycle of current flowing through one of the electronic switches. A current sense circuit may measure the current flowing through one of the electronic switches. An inductor voltage sensor circuit may measure the voltage across…
Switch mode power supply with dynamic topology
Granted: September 25, 2012
Patent Number:
8274266
A power supply system has an inductive device, a plurality of switching devices for providing connection of the inductive device to input and output nodes and a ground node, and a switch driver circuit for driving the switching devices so as to enable the power supply to operate in a boost mode to increase the input voltage, in a buck mode to decrease the input voltage, and in a solid-state flyback mode to transfer between the boost mode and the buck mode. In the solid-state flyback…
Error amplifier for regulating single feedback input at multiple levels
Granted: September 25, 2012
Patent Number:
8274314
An error amplifier may be part of a voltage regulator and may include a single feedback input configured to receive a feedback signal. A single error output may be configured to provide an error output signal indicative of error in the feedback signal. A comparison circuit may be configured to provide an error signal to the single error output which is indicative of a difference between the feedback signal and whichever one of a set of reference signals is closest to the feedback signal.…
Flexible contactless wire bonding structure and methodology for semiconductor device
Granted: September 18, 2012
Patent Number:
8269355
A semiconductor device such as a field-effect transistor, improved to reduce device resistance, comprises a leadframe which includes a die paddle integral with a first set of leads and a second set of leads that is electrically isolated from the first set, a semiconductor die having its lower surface positioned on, and electrically connected to, the die paddle, and a conductive layer on the upper surface of the die. At least one electrically conductive wire, preferably plural wires,…
Method and system for dimming an offline LED driver
Granted: September 11, 2012
Patent Number:
8264165
An apparatus and method for dimming a light emitting diode (LED) driver. The apparatus includes a triode alternating current (TRIAC) dimmer and an LED driver receiving an input voltage from an output of the TRIAC dimmer so that the state of the LED driver is controlled by the TRIAC dimmer. The LED driver includes an active damping circuit configured for damping, upon detecting a rising edge of a bridge rectified input voltage, resonance caused by the TRIAC dimmer and the LED driver for a…
High dynamic range coulomb counter which simultaneously monitors multiple sense resistors
Granted: July 31, 2012
Patent Number:
8233582
A circuit may include a source of electrical energy and a plurality of current loads. Each load may be of a different amount. For each current load, a resistance may be in series between the source and the current load. The resistance may be weighted inversely proportional to the amount of the current load with respect to the other resistances. For each resistance, an integrator may generate an integrated output representative of an integration of the current traveling through the…
Sequentially configured analog to digital converter
Granted: July 31, 2012
Patent Number:
8232905
An analog-to-digital converter (ADC) system and method. The ADC system includes a digital control circuit, an amplifier, a capacitor, and an evaluation circuit. The digital control circuit is configured to sequentially configure the ADC system in a first configuration and a second configuration to derive a digital representation of an analog signal value. The amplifier circuit includes an amplifier input terminal and an amplifier output terminal. The capacitor has a first capacitor…
Configurable data port for I2C or single-wire broadcast interface
Granted: July 24, 2012
Patent Number:
8230151
A device having a signal level different from a signal level of an external device includes an interface, such as an I2C interface, for providing communications with the external device. The interface is configurable to support communications with the external device either via multiple wires or via a single wire.
Pulse-width modulation (PWM) with independently adjustable duty cycle and frequency using two adjustable delays
Granted: June 26, 2012
Patent Number:
8207773
A pulse width modulation circuit may generate an adjustable output signal that periodically transitions between a first and a second state with an adjustable duty cycle. A first pulse generator circuit may be configured to generate a first pulse signal that periodically transitions at an adjustable delay with respect to a periodic reference signal. A second pulse generator circuit may be configured to generate a second pulse signal that periodically transitions at an adjustable delay…
Switching mode converters
Granted: June 19, 2012
Patent Number:
8203320
A switch mode converter converts an input DC voltage applied at one level at the converter input to an output DC voltage at a second level at the converter output. A switch is arranged to switch the input DC voltage on and off during each cycle of a plurality of cycles. An energy storage unit temporarily stores energy from the input source voltage when the switch is on, and releases energy when the switch is off during each cycle. Input energy stored is equal to the energy released with…
Method and system for extending PWM dimming range in LED drivers
Granted: June 12, 2012
Patent Number:
8198832
An apparatus for driving a light emitting diode (LED). A rising edge of a pulse width modulation (PWM) signal is first sensed. Upon sensing the rising edge, a threshold pulse (TP) signal is initiated that has a configured width started when the rising edge is sensed, an LED current with an amplitude at a previously set level is generated, and starting to charge a capacitor which yields a voltage Vcap. Subsequently, a falling edge of either the PWM signal or the TP signal is detected.…
System and method for charging capacitors using automatic cell balancing
Granted: June 12, 2012
Patent Number:
8198869
A circuit for charging a capacitor block including series-connected capacitive elements has an input node for receiving an input, an output node coupled to the capacitor block, a third capacitive element connectable to the input node and the output node, and first and second switching circuitries coupled to the third capacitive element. A voltage sensor determines a relationship between first voltage at the first capacitive element and second voltage at the second capacitive element to…
Inrush current control system with soft start circuit and method
Granted: June 5, 2012
Patent Number:
8194379
A method of and system for controlling the inrush current generated in a MOSFET of an inrush current control system, wherein the MOSFET includes a source, gate and drain. The dV/dt at the drain of the MOSFET is controlled so as to set the inrush current level as a function of dV/dt, independent of current limit without requiring a separate capacitor connected between the gate and drain of the MOSFET so that the MOSFET can turn on and off more quickly.
Method and system for communicating multiple data signals over a single unidirectional isolation component
Granted: May 8, 2012
Patent Number:
8175087
Method and system for serially sending data signals captured from multiple sources through a single unidirectional isolation component. Data signals from respective multiple sources are captured in parallel. Such captured data signals are stored in respective storages. The stored data signals are transferred, in serial, from the storages to a single unidirectional isolation component. Multiple concurrent processes for parallel data signal capture and serial data signal transfer via a…
Enhanced pad design for solder attach devices
Granted: April 24, 2012
Patent Number:
8163643
A semiconductor device is disclosed that has a die and a substrate having a die attachment area with a perimeter. A layer of solder connects the substrate and the die, the solder layer having at least one vent channel connected to the perimeter of the die attachment area, wherein the maximum distance from any point in the solder layer to the nearest free surface of the solder at a vent channel or at the perimeter of the die is less than the distance from the center of the die to the…
Method for clamping a semiconductor region at or near ground
Granted: April 17, 2012
Patent Number:
8159278
A clamping circuit clamps a voltage received by an n-type semiconductor region without using a Schottky transistor. The clamping circuit includes a current mirror as well as first and second bipolar transistors. The current mirror receives a first current and supplies a second current in response. The first current is received by the first bipolar transistor, and the second current is received by the second bipolar transistor. The difference between the base-emitter junction voltages of…
