Power sourcing equipment having bipolar junction transistor for controlling power supply and supporting AC disconnect-detection function
Granted: September 6, 2011
Patent Number:
8014412
A power supply system for providing power to a powered device over a communication link includes a power supply device capable of supporting an AC disconnect-detect function. The power supply device has a controller, an output port coupled to the communication link, and a bipolar junction transistor (BJT) controlled by the controller to provide power to the output port. The BJT may be turned off to present a high impedance required to support the AC disconnect-detection function.
Chopper stabilized bandgap reference circuit and methodology for voltage regulators
Granted: August 23, 2011
Patent Number:
8004266
A chopper stabilized bandgap voltage reference circuit comprises current mirror circuitry mirroring first and second currents into first and second networks to generate a forward diode voltage signal and a PTAT (proportional to absolute temperature) component signal, and a third current having a derived temperature coefficient into a third network to generate a reference voltage signal for a regulator. An amplifier amplifies a differential signal of the forward diode voltage signal and…
Circuits and methods for adjustable peak inductor current and hysteresis for burst mode in switching regulators
Granted: August 2, 2011
Patent Number:
7990120
Switching regulator circuits and methods are provided for regulating output voltage that include an adjustable minimum peak inductor current level and adjustable burst comparator hysteresis for Burst Mode operation in switching regulators. Control over minimum peak inductor current level and burst comparator hysteresis is achieved during Burst Mode operation by allowing external user control of the burst threshold level and the burst comparator hysteresis. A single user-accessible input…
Method and system for improved phase noise in a BiCMOS clock driver
Granted: June 28, 2011
Patent Number:
7969189
System and method for a clock driver. An input taking circuit is used for receiving small-signal logic inputs. A voltage follower circuit is coupled to the input taking circuit and used to generate a set of voltage follower outputs. An output circuit is coupled to the voltage follower circuit to receive the set of voltage follower outputs as inputs and generate output signals. The voltage follower circuit is coupled to a switching circuit, that is connected to the set of voltage follower…
Flexible contactless wire bonding structure and methodology for semiconductor device
Granted: June 14, 2011
Patent Number:
7960845
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,…
Sampling switch and controller
Granted: June 14, 2011
Patent Number:
7961132
In one embodiment, an A/D converter samples an analog input signal voltage by applying the input signal to a first capacitor terminal, while a second capacitor terminal is connected to ground via an NMOS sampling switch, to charge the capacitor to the input signal voltage. During an analog-to-digital conversion process, the second capacitor terminal may swing in a voltage range that extends below ground. A controller circuit provides bias voltage signals to a gate terminal and to a…
Bootstrapped switch for sampling voltages beyond the supply voltage
Granted: May 10, 2011
Patent Number:
7940091
Methods and apparatus for sampling an input voltage and apparatus incorporating the same are disclosed. An input voltage sampling apparatus includes a voltage sampling circuit coupled to the input voltage and configured to produce a sampled input voltage at an output terminal, and a voltage charging circuit coupled to the voltage sampling device and producing a first charged voltage on a first charged voltage output terminal and a second charged voltage on a second charged voltage output…
Systems and methods for oscillation suppression in switching circuits
Granted: April 5, 2011
Patent Number:
7920013
A switching circuit configured to reduce the effects of signal oscillation on the operation of the switching circuit is provided. The switching circuit may include signal oscillation and detection circuitry that suppresses control signals during a detected oscillation, allowing stored energy to naturally decay in the switching circuit and thereby prevent unwanted extension of the oscillation that may be caused by the repeated switching of a semiconductor element coupled between the input…
Monolithic voltage reference device with internal, multi-temperature drift data and related testing procedures
Granted: April 5, 2011
Patent Number:
7920016
A testing procedure may determine whether a monolithic voltage reference device meets a temperature drift specification. A first non-room temperature output voltage of the monolithic voltage reference device may be measured while the monolithic voltage reference device is at a first non-room temperature which is substantially different than room temperature. First non-room temperature information may be stored in a memory within the monolithic voltage reference device which is a function…
Complex-admittance digital-to-analog converter
Granted: March 29, 2011
Patent Number:
7916057
A circuit includes a digital-to-analog converter configured to produce an analog output signal (1) proportional to a reference signal and (2) as a function of a digital input signal. The converter comprises a plurality of non-trivially complex admittances configured so that each non-trivially complex admittance can be selectively switched as a function of the digital input signal so as to be coupled between a reference terminal configured to receive a reference signal and an output…
Circuits and methods to reduce or eliminate signal-dependent modulation of a reference bias
Granted: March 15, 2011
Patent Number:
7907074
Circuits and methods that improve the performance of voltage reference driver circuits and associated analog to digital converters are provided. A voltage reference driver circuit that maintains a substantially constant output voltage when a load current is modulated by an input signal is provided. The voltage reference driver circuit synchronously decouples a voltage regulation circuit from the load circuit when modulating events such as pulses caused by the load circuit during a…
Semiconductor device having a suspended isolating interconnect
Granted: March 8, 2011
Patent Number:
7902665
A semiconductor device is configured to provide current and voltage isolation inside an integrated circuit package. The semiconductor device includes first and second semiconductor dies, a first isolating block positioned on the first semiconductor die, and a second isolating block positioned on the second semiconductor die. The semiconductor device also includes a first interconnect coil having a plurality of wires connecting the first semiconductor die to the second isolating block,…
Peak charging current modulation for burst mode conversion
Granted: February 22, 2011
Patent Number:
7893665
During burst mode operation of a four switch buck-boost converter, the input voltage and an output voltage can be detected and a preset peak charging current threshold level can be modulated when the difference between the input voltage and output voltage is within a prescribed range. A burst mode charging cycle will progress until the modulated peak charging threshold level is attained and cut off at the set peak level. A charge transfer cycle and discharge cycle may proceed thereafter.
Balancing current drawn from multiple power supply inputs using multiple-input inductors
Granted: January 4, 2011
Patent Number:
7863772
Novel techniques for balancing current drawn from multiple power supply inputs. A multiple-input inductor is coupled between the power supply inputs and the switching circuits associated with the respective power supply inputs for balancing voltages applied to each of the switching circuits.
Detecting legacy powered device in power over ethernet system
Granted: December 21, 2010
Patent Number:
7856561
Novel system and methodology for detecting a Powered Device (PD) in a Power over Ethernet (PoE) system. A PD probing circuit generates a detection signal supplied to the PD and determines a PD response signal produced in response to the detection signal. Based on the PD response signal, the control circuit determines a detection value for identifying the PD. In particular, the control circuit concludes that the PD is a device satisfying a PoE standard if the detection value is in a first…
High linearity digital variable gain amplifier
Granted: November 30, 2010
Patent Number:
7843038
Variable gain amplifiers offering high frequency response with improved linearity and reduced power dissipation are provided. An amplifier is disclosed that is constructed from a one-stage topology with multiple signal paths and compensation networks for improved linearity and stable operation. In this amplifier, improved performance is obtained by replacing single transistor components with enhanced active devices which incorporate local negative feedback. One embodiment of the…
DC/DC converter startup with frequency ramping
Granted: November 30, 2010
Patent Number:
7843178
Control circuitry controls a boost regulator during a start-up period. The control circuitry may comprise an oscillator for generating a clock signal. The oscillator may be configured for ramping up a frequency of the clock signal in accordance with an voltage to be applied to the oscillator and varied during the start-up period. The control circuit may further include a switching circuit configured for controlling a power switch of the boost regulator in response to the clock signal…
Regulated power supply system and an operating method therefore
Granted: November 16, 2010
Patent Number:
7834600
A power supply system includes a regulator for receiving an input voltage and producing an output voltage, the regulator including an output device and a controller coupled to the regulator. The controller is configured to monitor at least one operating parameter of the output device and, in response, generate a control signal that adjusts the input voltage to a minimum input voltage needed to maintain the output device in saturation regardless of variation in the monitored operating…
Integrated powered device connector in system for supplying power over communication link
Granted: November 9, 2010
Patent Number:
7831844
An integrated connecting device for coupling a communication link to a powered device (PD) in a system for supplying power to the PD over the communication link. The integrated connecting device has a housing configured for providing connection to the PD external with respect to the housing, communication interface circuitry coupled to the communication link for supporting data communication of the PD over the communication link, and power interface circuitry coupled to the communication…
Feedback circuitry and methodology for switching circuit capable of generating both positive and negative output voltages
Granted: November 2, 2010
Patent Number:
7825665
Circuitry arranged for sensing a variable polarity signal comprises an input node supplied with the variable polarity signal to produce an input signal. A first sensing circuit is responsive to the input signal having a first polarity for producing a first signal. A level shifting circuit is responsive to the input signal having a second polarity for shifting a level of the input signal to produce a shifted signal of the first polarity at a level determined by the input signal.
