Network with multiple adjustment elements and sensitivities, and digital-to-analog converter implementing same
Granted: August 14, 2007
Patent Number:
7256721
A network comprises an arrangement of regular structures and merged structures, in which the regular structures each comprise one or more mutually identical fixed elements and an equal number of adjustable elements of equal value, and the adjustable elements each comprising two or more adjustable units. The regular structures may comprise one or more mutually identical fixed elements and an equal number of adjustable elements of equal value. The adjustable elements each comprise two or…
Light load current-mode control for switched step up-step down regulators
Granted: August 14, 2007
Patent Number:
7256570
A switched regulator circuit provides step-up and step-down operation at high efficiency during light load conditions. Switching loss is reduced in a four switch arrangement by limiting bottom MOSFET switching frequency. The possibility of overcharge in boost mode operation has been avoided by automatically changing to a buck mode operation in response to sensed parameters.
High linearity digital variable gain amplifier
Granted: July 17, 2007
Patent Number:
7245189
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…
Circuits and methods for current measurements referred to a precision impedance
Granted: July 17, 2007
Patent Number:
7246016
Circuitry and methods for obtaining accurate measurements of current supplied by an integrated circuit are provided. Current calculations are performed using information from a precision termination resistor and from the ratio relationship of two on-chip resistors. The invention provides a way to obtain accurate current measurements without the use of component trimming.
Multi-bit digital input using a single pin
Granted: July 3, 2007
Patent Number:
7239251
Electronic devices, and methods, for transmitting, transferring and/or conveying a multi-bit digital signal as a voltage signal via a single pin. Devices and methods according to the invention substantially reduce the pin count of a device because inputting of a multi-bit digital signal preferably does not use more than one input pin. In addition, the speed of transmission is improved because the multi-bit digital signal is transmitted as a voltage signal substantially at one time as…
Distinguishing network interface card from short circuit condition in power over ethernet system
Granted: June 12, 2007
Patent Number:
7230412
Novel system and methodology for distinguishing a Network Interface Card (NIC) from a short circuit condition in a Power over Ethernet (PoE) system. A system for providing power to a powered device (PD) includes a PD probing circuit that generates a detection signal supplied to a device being probed and determines a response signal produced in response to the detection signal, and a control circuit that determines a detection value based on the response signal. The control circuit…
System for controlling frequency of oscillator
Granted: June 12, 2007
Patent Number:
7230497
System for controlling the frequency of an oscillator. A first circuit is coupled to the oscillator and arranged for receiving an externally provided clock signal at a first input node. A second circuit coupled to the oscillator is arranged for receiving an externally provided frequency reference input at a second input node. The first circuit uses the clock signal received at the first input node to control the frequency of the oscillator. In absence of a clock signal received at the…
Method and circuit for driving a gate of a MOS transistor negative
Granted: May 29, 2007
Patent Number:
7224204
A method and circuit for driving the gate of a MOS transistor having a negative or low threshold voltage negative, in which the driving circuit is formed on a single chip. A negative voltage is generated from a positive voltage to drive the gate of the MOS transistor negative. The MOS transistor may be a native NMOS transistor, and the negative voltage is generated for increasing source-drain impedance of the native NMOS transistor. On the other hand, the MOS transistor may be a PMOS…
Compensation technique providing stability over broad range of output capacitor values
Granted: May 15, 2007
Patent Number:
7218082
A disclosed amplifier and buffer circuit, for example for a linear voltage regulator, comprises an input gain stage, an integrator and a unity-gain output stage. An output stage compensation scheme enables stable operation over a broad range of output capacitance. For low to moderate output capacitance, the design of the output stage effectively pushes the output pole to high frequencies while an internal pole provided by the integrator is dominant and rolls off the gain at lower…
Voltage offset measurement for calibration of an integrated circuit amplifier
Granted: May 15, 2007
Patent Number:
7218171
Voltage offset of an integrated circuit amplifier is accurately determined for calibration of the device. Circuit connections are established between the integrated circuit and an external device, such as an IC handler. Internal noise gain resistors formed within the integrated circuit are connected by internal switches to the amplifier and the output voltage is measured so that a value of a voltage offset of the amplifier while the noise gain resistors are connected can be calculated.…
High-linearity differential amplifier with flexible common-mode range
Granted: May 8, 2007
Patent Number:
7215200
An amplifier includes differential current sensing circuitry and an input bridge. Two paths of the input bridge receive the input signals and provide proportional current flows to the differential current sensing circuitry. The input bridge is configured to provide a differential offset voltage in one current path, and a complimentary voltage drop of equal magnitude in the other current path. In the examples, the input bridge includes a matched pair of transistors. To remove parallel…
Method of and system for regulating output voltage
Granted: May 1, 2007
Patent Number:
7212012
A method of and system for regulating voltage supplied by a local power supply to a remote load includes sensing a low frequency portion of the output voltage at the remote load, locally sensing a high frequency portion of the output voltage produced by the local power supply, and in response, controlling the output of the supply.
CMOS driver with minimum shoot-through current
Granted: April 24, 2007
Patent Number:
7208984
A CMOS driver with minimum shoot-through current is disclosed. The potential for shoot-through current may be eliminated or reduced with a break-before-make circuit driving an output stage. The break-before-make circuit may include a first logic element followed by a first inverter and a second logic element followed by a second inverter. The inverters may be cross-coupled to one another and/or the internal transistors may be configured with different strengths. The logic elements may be…
Ultra-wideband constant gain CMOS amplifier
Granted: April 10, 2007
Patent Number:
7202748
Circuitry and methods for improved amplifiers with large bandwidth and constant gain are provided. The combination of a synthetic inductive drain load and a bridged-T matching network provide amplifiers that can drive a substantial capacitive load with the above mentioned improvements over prior amplifiers. Additionally, circuits presented allow for improved rise time and insensitivity to temperature variations.
Switch-mode power supply voltage regulator and methodology
Granted: April 3, 2007
Patent Number:
7199560
Pulse width modulation of the connection of a load output terminal to a power supply terminal is effected. In response to a first level of the pulse width modulated signal, the load is disconnected from the power supply terminal, steady-state load voltage is preserved on a capacitor connected between a load output terminal and a power supply terminal, and steady-state load current information is held on a capacitor within the feedback loop. In response to a second level of the pulse…
System and method for transferring duty cycle information in an isolated DC/DC converter or other circuit
Granted: April 3, 2007
Patent Number:
7200014
A signal processing methodology and circuit for supplying bias power and duty cycle information across an isolation barrier, wherein, at an input side of the isolation barrier at least one input signal carrying input duty cycle information, together with DC bias power, is received and encoded on a constant repetition rate, constant duty cycle carrier waveform. Encoding is carried out by an encoder implemented to encode the carrier waveform with a marker, such as a waveform discontinuity,…
High-speed, current driven latch
Granted: February 13, 2007
Patent Number:
7176736
A high-speed, current-driven latch is provided. The latch conducts a current and includes an output, a SET circuit and a RESET circuit. The output is variable between a first state and a second state. The SET circuit conducts the current present in the latch at the first state such that the SET circuit is maintained close to a level required to change the output of the transistor from the first to the second level, and the RESET circuit conducts the current at the second level such that…
High-speed, current-driven latch
Granted: February 6, 2007
Patent Number:
7173465
A high-speed, current-driven latch is provided. The latch conducts a current and includes an output, a SET circuit and a RESET circuit. The output is variable between a first state and a second state. The SET circuit conducts the current present in the latch at the first state such that the SET circuit is maintained close to a level required to change the output of the transistor from the first to the second level, and the RESET circuit conducts the current at the second level such that…
Load-generated drive, no quiescent current, techniques and circuits for high speed switching of transistors
Granted: February 6, 2007
Patent Number:
7173474
Techniques and circuits for high speed switching of transistors are provided. These techniques and circuits switch an output device while varying the drive current to the output device in proportion to the output current through the output device. In addition, these techniques and circuits provide a switching circuit with substantially no quiescent currents. This is accomplished by sampling the output current conducted by the output device and using the sample as a signal to drive either…
Circuits and methods for flexible current partitioning in monolithic switching regulators
Granted: January 30, 2007
Patent Number:
7170195
A monolithic switching regulator that flexibly distributes its output current among its output channels is provided. The monolithic switching regulator includes one or more additional channels that are externally connected to the output channels for providing additional current partitioning configurations. The external connections may be autosensed or programmed with an additional input pin. A switching logic circuit is provided for distributing the current among the output channels…
