Patent classifications
H03G1/00
Apparatus and method for filter settling calibration to improve speed of tracking and cancelling of DC offset
Described is an apparatus which comprises: an amplifier to receive a reference voltage; and calibration logic which is operable to receive a first voltage and to provide the reference voltage to the amplifier, wherein the calibration logic is operable to generate a look-up table (LUT) that maps the first voltage to a drive current.
Overload protection for power converter
A method includes comparing a value of a current sense signal indicating an output signal of a power converter to a value of a threshold signal, adjusting a value of a first count signal in response to the comparison result, and determining whether or not the power converter is operating in an overload condition using the first count signal. A circuit includes an overload monitor comparing a value of a current sense signal to a value of a threshold signal, adjusting a value of a first count signal in response to the comparison result, and determining whether or not the power converter is operating in an overload condition using the first count signal. The circuit further includes an overload protection signal generator generating an overload protection signal indicating whether or not the power converter is operating in the overload condition.
Passive bias temperature compensation circuit module
A passive bias temperature compensation module for silicon photomultiplier, avalanche photodiodes and similar photodetectors that possess a moderately linear temperature coefficient of gain and that may be compensated by varying an applied bias voltage. The module includes an electrical circuit and a method for determining component values to provide a constant voltage source to stabilize the gain of one or more photodetector devices. A temperature sensor in the module is held in close thermal contact with the photodetector and a filter capacitor is electrically close to the photodetector. The module is based on the concept of temperature sensitive voltage division which is applicable to situations in which large numbers of photodetectors must be gain-compensated for temperature variations over a wide range while maintaining excellent gain matching. The passive bias temperature compensation method enables multiple photodetectors to share a single constant voltage supply without loss of matching performance.
CONTROL OF SWITCHES IN A VARIABLE IMPEDANCE ELEMENT
In accordance with embodiments of the present disclosure, a system may include a buffer and a switch coupled between the buffer and a voltage supply such that the switch controls a varying voltage at a varying voltage node coupled to the buffer.
Variable gain power amplifiers
A variable-gain power amplifying technique includes generating, with a network of one or more reactive components included in an oscillator, a first oscillating signal, and outputting, via one or more taps included in the network of the reactive components, a second oscillating signal. The second oscillating signal has a magnitude that is proportional to and less than the first oscillating signal. The power amplifying technique further includes selecting one of the first and second oscillating signals to use for generating a power-amplified output signal, and amplifying the selected one of the first and second oscillating signals to generate the power-amplified output signal.
Circuit and a method for operating a circuit
A circuit containing a first cascode circuit and a second cascode circuit is proposed. The first circuit and the second cascode circuit are stacked between two power supply terminals. An output signal terminal of the circuit is coupled to a node connecting the first cascode circuit and the second cascode circuit. A first signal path is provided between the first cascode circuit and a common ground terminal and a second signal path is provided between the second cascode circuit and the common ground terminal.
Amplifier architectures with bypass circuits and resonant structures
The disclosed technology is related to a radio-frequency (RF) amplifier having a bypass circuit and a resonant structure to improve performance in a bypass mode (e.g., a low gain mode). The disclosed amplifiers have a resonant structure that effectively isolates an amplifier core from a bypass circuit. For example, in a bypass mode, the resonant structure is configured to create an open impedance looking into the amplifier core input. This effectively removes any loading from the amplifier core to the bypass circuit. The disclosed amplifiers with resonant structures improve linearity performance in bypass modes due at least in part to the open impedance to the amplifier core provided by the resonant structure.
LED driving device
An LED driving device includes an LED string including at least first and second LED elements connected in series, first and second channels coupled to output nodes of the first and second LED elements, respectively, first and second regulators to regulate a current flowing through the first and second channels in response to first and second control voltages, respectively, and a control voltage generating circuit to generate the first and second control voltages based on a difference between a reference voltage and a comparative voltage, the comparative voltage being generated based on a sensing voltage, the sensing voltage corresponding to an LED current flowing through the LED string. The control voltage generating circuit includes a reference voltage generator to generate the reference voltage based on an input voltage and the dimming signal, the input voltage being supplied to the LED string, the dimming signal controlling dimming of the LED string.
MULTI-INPUT AMPLIFIER WITH VARIABLE GAIN FOR INDIVIDUAL INPUTS
Described herein are variable gain amplifiers and multiplexers that embed programmable attenuators into switchable paths to provide variable gain for individual amplifier inputs. The variable gain for an individual input is provided using a amplification stage that is common for each input of the amplifier. A variable attenuation is provided for individual inputs through a combination of a band selection switch and an attenuation selection branch. The attenuation can be tailored for individual inputs and can depend on a gain mode of the amplifier.
Dynamic amplifier and related gain boosting method
A dynamic amplifier includes a first output capacitor, a first switch, a current source, a second switch, a voltage detector, a third switch and a level shifter. The first switch is coupled between a first terminal of the first output capacitor and a voltage detection node. The second switch is coupled to the current source and the voltage detection node. The voltage detector is coupled to the voltage detection node and the first switch. The third switch is coupled between the voltage detection node and a power source. The level shifter is coupled to a second terminal of the first output capacitor.