DC/DC power converter with feedback control operable in linear and non-linear modes
Granted: October 20, 2015
Patent Number:
9166473
A current mode power conversion system and method operates in cycles. Each cycle includes an on time and an off time. The system includes an inductor connected to store energy during the on time of each cycle and use the energy during the off time of each cycle. The system provides a stable output voltage and a maximum-limited output current to a load during constant load conditions. The system comprises a feedback control linearly operable so as to control the output voltage across the…
Linear regulator IC with versatile ground pin
Granted: October 6, 2015
Patent Number:
9152158
A linear regulator integrated circuit may be formed having four external terminals including a voltage input (Vin) terminal, a voltage output (Vout) terminal, a Set terminal, and an operational amplifier (op amp) power terminal. A user connects an external resistor to the Set terminal for creating a reference voltage. An op amp controls a pass (or series transistor) to cause an output voltage at the Vout terminal to equal the reference voltage. The op amp has a first power supply…
Low current DC-DC converter with integrated low current Coulomb counter
Granted: September 15, 2015
Patent Number:
9134744
A power supply system includes a regulator circuit responsive to an input signal at the input node for producing an output signal at the output node at a desired level. The regulator circuit has a controller, an inductive element and a first switch coupled to the inductor element and controlled by the controller to produce the output signal. Also, the power supply system includes a Coulomb counter for producing a Coulomb count signal proportional to the number of Coulombs passing from…
Circuits for and methods of accurately measuring temperature of semiconductor junctions
Granted: August 25, 2015
Patent Number:
9116048
A system for and method of providing a signal proportional to the absolute temperature of a semiconductor junction is provided. The system comprises: a preprocessing stage configured and arranged so as to process a signal from the semiconductor junction so as to produce a preprocessed signal including a resistance error term; and a temperature to voltage converter stage for converting the preprocessed signal to a voltage proportional to absolute temperature representing the absolute…
Poly-phase filter with phase tuning
Granted: August 11, 2015
Patent Number:
9106202
A poly-phase filter receives inphase input signals I and ? and quadrature input signals Q and Q, and provides inphase output signals Iout and Iout and quadrature output signals Qout and Qout. The capacitance of each variable capacitor connected to the terminals providing inphase output signals Iout and Iout is and the capacitance of each variable capacitor connected to the terminals providing quadrature output signals Qout and Qout, are different in value, and preferably by twice a…
Low power timing, configuring, and scheduling
Granted: August 11, 2015
Patent Number:
9104418
A device reduces its energy consumption using a relatively lower frequency and lower power secondary oscillator to maintain timing information when a higher frequency and higher power primary oscillator is inactivated. The secondary oscillator maintains timing information at a higher resolution than the period of the oscillator, so as to conserve synchronization when the higher frequency, higher power primary oscillator is inactivated. In some embodiments, a microsequencer is…
Floating output voltage boost regulator driving LEDs using a buck controller
Granted: July 7, 2015
Patent Number:
9078317
An LED driver uses a positive-to-floating boost converter topology to generate a negative voltage ?Vee relative to ground. The converter receives an input voltage. Vin from a power supply. One end of an output inductor is coupled to ground, and the other end of the inductor is coupled between a highside switch and a low side switch. The bottom terminal of the lowside switch generates ?Vee. The anode end of an LED string is coupled to Vin and the cathode end is coupled to ?Vee. The…
Resolution-boosted sigma delta analog-to-digital converter
Granted: July 7, 2015
Patent Number:
9077374
A method and an ADC circuit use multiple SD modulations on an analog value and apply digital post-processing of the pulse density modulation (PDM) streams from the SD modulations obtaining a higher resolution in the digital output value for a given oversampling ratio. SD ADC does not face the constraint of conversion time doubling for each additional bit of resolution. In one implementation, an SD ADC includes conversions in SD phase and resolution-boosting phase. During SD phase, MSBs…
Expanding DC/DC converter into multiphase DC/DC converter
Granted: July 7, 2015
Patent Number:
9077244
A DC/DC converter configurable for operating as a multiphase DC/DC. A controller produces a master drive signal for controlling a primary power switch to produce the output DC signal at a desired level. Multiple secondary power stages are coupled between the input and the output nodes for producing an output DC signal. Each of the multiple secondary power stages has at least one secondary power switch responsive to the input DC signal for producing the output DC signal. An expander…
Pre-charging inductor in switching converter to achieve high PWM dimming ratio in LED drivers
Granted: June 30, 2015
Patent Number:
9072147
In a method for controlling a current regulator for dimming an LED load, a dimming signal has a duty cycle that controls the LED ON-time and LED OFF time at a fixed frequency. The regulator is controlled by the dimming signal to only supply current to the LED load during the LED ON-time. The regulator includes an inductor. The inductor current at the end of an ON-time is detected and its value is stored. During the OFF-time, the inductor is pre-charged to the current level matching the…
Light load stability circuitry for LDO regulator
Granted: June 30, 2015
Patent Number:
9069368
A linear regulator contains an additional AC-coupled feedback loop between the output of the error amplifier and the base of the pass transistor that increases the frequency of the pole at the output of the error amplifier at light load currents to at least partially offset the decreased frequency of the output pole at the lighter load currents. Thus, a desired phase margin is preserved. The AC-coupled feedback loop includes a bipolar feedback transistor connected in parallel with the…
Analog-to-digital converter system and method
Granted: June 9, 2015
Patent Number:
9054727
An analog-to-digital converter (ADC) system and method. The ADC system in accord with one embodiment includes a sampling digital-to-analog converter configured to sample a combination of an analog signal value and an analog dither value, and a control circuit comprising a mismatch-shaping encoder. The control circuit is configured to sequentially apply a plurality of digital codes to the sampling digital-to-analog converter during an analog-to-digital conversion operation to derive a…
Primary unit control of resonant inductive power transfer system for optimum efficiency
Granted: May 26, 2015
Patent Number:
9041254
A circuit and method for wirelessly coupling an electrical energy between an electrical energy source and at least one load is provided. The circuit comprises a primary unit and at least one secondary unit. The primary unit includes an input node for receiving an input voltage produced by the energy source; a transmitter circuit including a transmitter coil configured to generate an electromagnetic field; and a regulator. The regulator is configured to sense a current consumption of the…
Polarity correction bridge controller for combined power over ethernet system
Granted: May 5, 2015
Patent Number:
9026809
A system for combining power to a load in a Powered Device (PD) using Power Over Ethernet (PoE) receives power from a first channel and power from a second channel, via four pairs of wires. A MOSFET bridge for each channel is initially disabled. A bridge controller IC simultaneously senses all the voltages and controls the bridge MOSFETs. The bridge controller IC also contains a first PoE handshaking circuit. A second PoE handshaking circuit is external to the bridge controller IC and…
Power combining in power over ethernet systems
Granted: May 5, 2015
Patent Number:
9024473
A technique for combining power to a single load from multiple power supplies using power over Ethernet (PoE) is disclosed. Each power supply is coupled to associated power sourcing equipment (PSE) providing PoE, and each PSE has a current limit. The power supplies supply approximately the same voltage, but the output voltages are typically not exactly equal. All the power supplies are connected via diodes to a common load terminal. The power supply outputting the highest voltage first…
Temperature compensation of output diode in an isolated flyback converter
Granted: April 28, 2015
Patent Number:
9019727
An isolated flyback converter having temperature compensation (TC) uses primary side sensing and an output diode, the output diode having a variable voltage drop related to its temperature. A feedback voltage VFB, proportional to the output voltage VOUT, in a feedback loop is compared to a fixed reference voltage VREF for setting a duty cycle of a power switch, wherein VFB is caused to approximately equal VREF. A TC circuit has a voltage source configured to generate a…
Single supply amplifier with swing to ground
Granted: April 7, 2015
Patent Number:
9000747
An amplifier circuit has a voltage input terminal, for receiving Vin, and a voltage output terminal, for outputting Vout. A feedback circuit controls Vout to match Vin. A differential input stage receives Vin and Vout and generates a first output signal. An output stage comprises a pull down circuit for Vout. A main MOSFET is controlled by the first output signal to pull down Vout to match Vin when Vout is above a threshold voltage Vtrans. An auxiliary MOSFET, in parallel with the main…
Pre-charging inductor in switching converter while delaying PWM dimming signal to achieve high PWM dimming ratio in LED drivers
Granted: March 10, 2015
Patent Number:
8975831
In a method for controlling a current regulator for dimming an LED load, an adjustable delay circuit generates a delayed second dimming signal from an original first dimming signal. The second dimming signal has a duty cycle that controls the LED ON-time and LED OFF time at a fixed frequency. An ON-time pulse of the first dimming signal starts a pre-charging of the regulator's inductor to approximately the inductor current previously detected at the end of the previous ON-time of the…
Switching topology for connecting two nodes in electronic system
Granted: February 24, 2015
Patent Number:
8963617
A circuit for providing connection between a first node at a first voltage and a second node at a second voltage. The circuit has a first inductive element having a first terminal coupled to the first node, a first switching element coupled between a second terminal of the first inductive element and the second node, a second inductive element having a first terminal configured for receiving current from the second terminal of the first inductive element, and having a second terminal…
Method and system for measuring the resistance of a resistive structure
Granted: February 3, 2015
Patent Number:
8947101
Method and system for measuring the resistance of a resistive structure having at least three nodes. A first calibration signal is determined by measuring a voltage at an output of the resistance structure when no calibration current is injected into a third node between the first and second nodes of the structure. A calibration current is then injected into the third node and a second calibration signal is determined. The absolute value of the difference between the first calibration…
