Patent classifications
H03F3/00
Method and system for a track and hold amplifier with extended dynamic range
Systems and methods for a track and hold amplifier with extended dynamic range may include a track amplifier comprising a first PMOS transistor coupled to a first NMOS transistor, a second PMOS transistor coupled to a second NMOS transistor, a capacitor at gates of each NMOS and PMOS transistor, and a plurality of switches. The track and hold amplifier is operable to, during a tracking mode of the track and hold amplifier, couple a differential input signal to each NMOS and PMOS transistor via a first switch coupled to a first capacitor coupled to the gate of the first PMOS transistor and a second capacitor coupled to the gate of the first NMOS transistor, and via a second switch coupled to a third capacitor coupled to the gate of the second PMOS and a fourth capacitor coupled to the gate of the second NMOS transistor.
Interface circuit for a capacitive accelerometer sensor
The present invention relates to an interface circuit for a capacitive accelerometer sensor for measuring an acceleration value sensed by the sensor. The interface circuit comprises a plurality of electrical switches and three programmable capacitors. Two of the programmable capacitors are arranged to implement gain trimming of the interface circuit, while one of the programmable capacitors is arranged to implement acceleration range selection.
I—V conversion module
An I-V conversion module includes: a current output type sensor, a pre-integral circuit, a charge transfer auxiliary circuit, and an I-V transformation circuit including an inverting amplifier. The current output type sensor is connected to an input end of the I-V transformation circuit through the pre-integral circuit. The charge transfer auxiliary circuit connects in parallel with the inverting amplifier. When both the pre-integral circuit and the charge transfer auxiliary circuit are open circuits, the pre-integral circuit pre-integrates the induction current output by the current output type sensor to store pre-integral charges. When both pre-integral circuit and the charge transfer auxiliary circuit are closed circuits, the pre-integral charges are transferred to the I-V transformation circuit. In these embodiments, both the time for establishing the I-V conversion module and power consumption can be reduced.
FLYING CAPACITOR VOLTAGE CONTROL IN AN AMPLIFIER
An amplifier comprises: an input stage, a pulse width modulation stage, and a switched output stage. During operation, the input stage receives an input signal (such as an audio signal). The input stage adjusts the input signal based on feedback from the switched output stage of the amplifier. According to one configuration, the feedback from the switched output stage is a voltage across a flying capacitor disposed in the switched output stage. The pulse width modulation stage uses the adjusted input signal or signals to produce respective pulse width modulation signals that are subsequently used to drive (control) switches in the switched output stage. The switches in the switched output stage generate an output voltage to drive a load based on states of the pulse width modulation signals. Adjustments applied to the input signal based on the feedback maintains the magnitude of the flying capacitor voltage at a desired setpoint.
AMPLIFIER ARRANGEMENT AND SENSOR ARRANGEMENT WITH SUCH AMPLIFIER ARRANGEMENT
An amplifier arrangement comprises a sensor input and a first and a second amplifier. The first amplifier has a first amplifier output and a first input connected to a first reference potential terminal and a second input connected to the sensor input in a direct fashion and to the first amplifier output via a feedback path having a switched integration capacitor that is charged by the feedback path during a first switching phase and discharged during a second switching phase. The second amplifier has a second amplifier output, a first input connected to a second reference potential terminal and a second input. A first feedback capacitor is connected in-between two pairs of feedback switches. A second feedback capacitor is connected between the second amplifier output and the second input of the second amplifier. An impedance element is coupled between the second amplifier output and the sensor input.
A MULTI-LEVEL CAPACITIVE DIGITAL-TO-ANALOG CONVERTER FOR USE IN A SIGMA-DELTA MODULATOR
A multi-level capacitive digital-to-analog converter, comprises at least one capacitor switch circuit (100) including a differential operational amplifier (130) having a first input node (E130a) and a second input node (E130b). A first current path (101) is coupled to a first reference input terminal (E100a) to apply a first reference potential (RefP) and the second current path (102) is coupled to a second reference input terminal (E100b) to apply a second reference potential (RefN). The at least one capacitor switch circuit (100) comprises a first controllable switch (111) being arranged between the second input node (E130a) of the differential operational amplifier (130) and the first current path (101). The at least one capacitor switch circuit (100) comprises a second controllable switch (112) being arranged between the first input node (E130a) of the differential operational amplifier (130) and the second current path (102).
Power amplifier with supply switching
A power amplifier with supply switching is provided. The power amplifier detects a magnitude of an outgoing broadband communication signal and determines whether the magnitude exceeds a predetermined voltage threshold. The power amplifier applies a first gain to the outgoing broadband communication signal using a first voltage supply rail when it is determined that the magnitude exceeds the predetermined voltage threshold and a second gain using a second voltage supply rail that is smaller than the first voltage supply rail when it is determined that the magnitude does not exceed the predetermined voltage threshold. The power amplifier produces an output signal from the outgoing broadband communication signal with the applied first gain or the applied second gain, wherein a current of the outgoing broadband communication signal is switched between the first voltage supply rail and the second voltage supply rail in response to the magnitude being detected.
Audio signal processor and method of processing audio signal
An audio signal processor includes a difference detecting circuit, a gain switching circuit, a differential gain value changing circuit, and a gain control circuit. The difference detecting circuit detects a differential gain value being a first total gain value being a gain value to be switched and a second total gain value being the gain value that has been switched. The gain switching circuit switches the first total gain value to the second total gain value. The differential gain value changing circuit decreases the differential gain value as time passes. The gain control circuit corrects an inputted signal with the differential gain value that decreases as time passes.
Low-noise amplifier system
A low-noise amplifier system is disclosed. The low-noise amplifier system includes a low-noise amplifier having an input node and an output node in a receive path and a capacitance equalization network coupled to the output node. Compensation capacitance of the capacitance equalization network sums with non-linear capacitance of the low-noise amplifier such that a total capacitance at the output node varies by no more than 5% over an output voltage range within voltage headroom limits of the low-noise amplifier for a given supply voltage of the low-noise amplifier. In at least some exemplary embodiments, the compensation capacitance of the capacitance equalization network is a function of output signal voltage at the output node.
Amplifier arrangement and switched capacitor integrator
An amplifier arrangement has a first differential stage with a first transistor pair, a second differential stage with a first and a second transistor pair, each pair having a common source connection. The amplifier arrangement further has a first complementary differential stage with a transistor pair having opposite conductivity type, and a second complementary differential stage with a first and a second transistor pair of the complementary conductivity type. The first and the second complementary differential stage are connected symmetrically compared to the first and the second differential stage. The transistors of the second differential stage and the second complementary differential stage are symmetrically connected to form respective first, second, third and fourth current paths. A pair of output terminals is coupled to the first and the fourth current path. Gate terminals of the transistors are coupled to a respective pair of input terminals.