Auto resonant driver for wireless power transmitter sensing required transmit power for optimum efficiency
Granted: April 5, 2016
Patent Number:
9305700
An auto-resonant driver for a transmitter inductor drives the inductor at an optimal frequency for maximum efficiency. The transmitter inductor is magnetically coupled, but not physically coupled, to a receiver inductor, and the current generated by the receiver inductor is used to power a load. The system may be used, for example, to remotely charge a battery (as part of the load) or provide power to motors or circuits. A feedback circuit is used to generate the resonant driving…
Arbitrary phase trajectory frequency synthesizer
Granted: March 29, 2016
Patent Number:
9300307
A frequency synthesizer directly generates phase modulated radio-frequency (RF) signals. The frequency synthesizer includes a voltage controlled oscillator (VCO) producing a synthesized frequency signal having a frequency controlled based on a signal received at an input of the VCO. A digitally adjustable frequency divider produces a reduced frequency signal from the synthesized frequency signal. A phase digital-to-analog converter (DAC) produces a delayed version of a timing signal…
Bootstrap sampling circuit with accurately averaging pre-charge circuit
Granted: March 15, 2016
Patent Number:
9287002
A sampling circuit may include a sampling capacitance, an electronic sampling switch, and a switch controller. The electronic sampling switch may have a control input that controls whether the electronic sampling switch is in a sample state or a hold state. The electronic sampling switch may connect the sampling capacitance to an input signal while in the sample state and disconnect the sampling capacitance from the input signal while in the hold state. The switch controller may control…
Predictive and reactive control of secondary side synchronous rectifiers in forward converters
Granted: February 23, 2016
Patent Number:
9270190
A forward converter has a primary side containing a PWM controller for controlling switching of a power switch and has a secondary side coupled to the primary side via a transformer. The secondary side includes a forward transistor and a catch transistor. A secondary side switch controller controls switching of the forward transistor and the catch transistor without communication from the primary side. The secondary side switch controller detects the rising and falling of the voltages at…
Monitoring cells in energy storage system
Granted: February 23, 2016
Patent Number:
9270133
A system for monitoring an energy storage system composed of multiple cells connected in series has a chain of monitors including at least first and second monitors. The first monitor is configured for monitoring at, least a first cell in the energy storage system to produce first monitored data. The second monitor is configured for monitoring at least a second cell in the energy storage system to produce second monitored data. The first monitor is further configured for transferring the…
IC isolated, bidirectional communication system with isolated domain current source pull-ups
Granted: February 9, 2016
Patent Number:
9256570
This disclosure describes a circuit implementation providing the functions necessary to implement an isolated I2C bidirectional port. The technique implements a current source as a pull up device on at least one side of the isolation system. The circuit manages and communicates bidirectional data across an isolation barrier. A method of communicating bidirectional signals and an I2C acknowledge (ACK) or clock stretching through an isolation channel is disclosed.
Voltage regulator sleep control in dropout mode
Granted: February 2, 2016
Patent Number:
9250638
A control circuit for controlling a switching regulator that converts an input voltage to a regulated output voltage. The control circuit has an input-output comparator configured for comparing a difference between the input voltage and the output voltage, and producing a first sleep signal for placing the regulator into a sleep mode, when the regulator operates in a dropout mode, and the difference between the input voltage and the output voltage becomes less than a first predetermined…
Low power radio receiver
Granted: January 26, 2016
Patent Number:
9246436
A method and device for receiving a wireless signal is provided. The device includes a passive mixer having a first input node, a second input node, and at least one output node. An oscillator is coupled to the first input node of the mixer. The output of a buffer is coupled to the second input node of the mixer. An antenna is operatively coupled to the input node of the buffer. The buffer is configured to provide isolation from the mixer.
System and method for input voltage regulation of switch mode supplies implementing burst mode operation
Granted: January 26, 2016
Patent Number:
9246383
Switching regulator methods and systems are provided for supplying output current at a regulated voltage level to a load. Upon determining that the output current is not below a predetermined current threshold, the regulator is operated in a continuous mode. The input voltage is monitored. If the input voltage is not below a first input threshold level, the system remains in continuous mode. Otherwise, the system enters a burst mode in which the switch mode power supply is turned OFF,…
Accurate current sensing in H-bridge applications without amplifier having high common mode rejection ratio
Granted: January 19, 2016
Patent Number:
9240718
A current sensing circuit may include a shunt resistance through which current to be sensed travels. A first and a second differential amplifier may each provide an amplified output of the voltage across the shunt resistance. A switching system may deliver a current sensing signal output based on the amplified output of the first differential amplifier when the common mode voltage across the shunt resistance is low and based on the amplified output of the second differential amplifier…
Linear broadband PNP amplifier
Granted: January 12, 2016
Patent Number:
9236840
A DC-coupled differential amplifier has an output common-mode voltage near the ground reference. A feedback circuit superimposed on a trans-linear loop improves linearity and extends the bandwidth of the basic PNP differential pair.
Analog-to-digital converter
Granted: January 5, 2016
Patent Number:
9231611
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…
Power over Ethernet on data pairs and spare pairs
Granted: December 8, 2015
Patent Number:
9209981
Power Sourcing Equipment (PSE) provides a PoE supply voltage over data wires to a Powered Device (PD). A PSE controller controls a first FET that couples the PoE voltage to the data wire pairs and controls a second FET that couples the data wire pairs to the spare wire pairs. Upon powering up, the PSE controller keeps the two FETs open and performs a detection routine on any devices connected to the data pairs and spare pairs. If a PoE-compatible PD is detected as being coupled to the…
Suppressing dielectric absorption effects in sample-and-hold systems
Granted: November 24, 2015
Patent Number:
9197235
Sample-and-hold (S/H) circuitry operating in track and hold phases and having a first S/H circuit with a first hold capacitor at which a first voltage value is maintained in the hold phase, and a dielectric absorption (DA)-suppressing circuit connectable to the first hold capacitor for operating the S/H circuitry in an additional phase after completing the hold phase and before entering the track phase. The DA-suppressing circuit is configured to supply the first hold capacitor, during…
Radar system and method for providing information on movements of object's surface
Granted: November 17, 2015
Patent Number:
9188477
A system for producing an output signal representing movement of an object's surface has a continuous wave (CW) signal source for producing an CW signal directed at the object's surface. The CW signal is produced at a first frequency. A receiving element receives a signal reflected from the object's surface when the CW signal hits this surface. A down-converting frequency mixer converts the received signal into a signal of a second frequency lower than the first frequency. The frequency…
Switched capacitance voltage differential sensing circuit with near infinite input impedance
Granted: November 10, 2015
Patent Number:
9182428
A circuit may sense the differential voltage across two nodes that each have a non-zero common mode voltage. The circuit may have a positive input impedance that is imposed across the nodes. An impedance compensation circuit may generate a compensation current that is delivered to the nodes that substantially cancels the loading effect of the positive input impedance. The impedance compensation circuit may generate a negative input impedance that is imposed across the two nodes that is…
Systems and methods for randomizing component mismatch in an ADC
Granted: November 10, 2015
Patent Number:
RE45798
Circuits and methods for converting a signal from analog to digital. A random number generator provides a random number to a memory. The memory is preconfigured to include codes of predetermined digital to analog (DAC) configurations that provide the maximum amount of DAC gradient suppression. At least one Flash reference generation DAC (FRGD) has an input coupled to the memory unit and an output providing a reference voltage level for its respective Flash comparator. The Flash…
Floating output voltage boost-buck regulator using a buck controller with low input and low output ripple
Granted: November 3, 2015
Patent Number:
9178427
A converter generates an output voltage differential across a floating load, such as a string of LEDs. The converter receives an input voltage Vin from a power supply, and the floating output voltage differential may be greater than or less than Vin. The converter uses a first switch and first inductor in a boost mode type configuration, and uses a second switch and second inductor in a buck mode type configuration. The inductors have a common node. The first inductor has another end…
Anemometer detecting thermal time constant of sensor
Granted: November 3, 2015
Patent Number:
9176163
An anemometer and method for analyzing fluid flow is described. In one embodiment, a transistor sensor is heated by applying power to cause its base-emitter junction to rise from an ambient first temperature to a second temperature. The power is removed, and the Vbe is measured at intervals as the junction cools. The Vbe equates to a temperature of the junction. The temperature exponentially decreases, and the time constant of the decay corresponds to the fluid flow velocity. A best fit…
Isolated bootstrapped switch
Granted: October 27, 2015
Patent Number:
9172364
A bootstrapped switch circuit capable of operating at input signals from far below the negative supply rail to far beyond the positive supply rail may include (a) a switch having a first terminal coupled to an input terminal, a second terminal coupled to an output terminal, and a control terminal; (b) a charge pump coupled to one or more clock signals and isolated from a timing circuit via a first capacitor and a second capacitor, the charge pump generating an output voltage; and (c) a…
