This application relates to an independent active electromagnetic interference filter module. In one aspect, the filter module includes a first element group including a noise sensing unit provided to sense electromagnetic noise, and a second element group including a compensating unit provided to generate a compensation signal for the electromagnetic noise. The first group and the second group may be respectively mounted on different substrates. According to some embodiments, the filter module can reduce a volume of each element constituting an electromagnetic interference filter module, implement a single modularization of a compact structure. The filter module can also improve electromagnetic interference noise reduction performance and a manufacturing method thereof.

In accordance with a first aspect of the present disclosure, an active RC-type filter is provided, comprising: an input, an output and a signal path between said input and output; at least one capacitor bank and at least one resistor bank, wherein said capacitor bank and resistor bank are integrated into the signal path; wherein the resistor bank comprises a plurality of resistor ladders; wherein each one of said resistor ladders comprises a plurality of resistors connected in series; wherein each one of said resistors has an input node configured to be coupled selectively to the signal path through one of a plurality of controllable switches; and wherein said resistor ladders have output nodes directly coupled to each other and to the signal path. In accordance with a second aspect of the present disclosure, a corresponding method of implementing an active RC-type filter is conceived.

The present application provides a window function processing module including an integrating circuit, configured to receive an integrating input signal, the integrating circuit comprising an operational amplifier; an integrating capacitor, coupled to an output terminal and a first input terminal of the operational amplifier; and an adjustable impedance module, coupled between the first input terminal of the operational amplifier and an integrating input terminal of the integrating circuit, wherein the adjustable impedance module is controlled by at least one control signal to adjust an impedance value of the adjustable impedance module; and a control unit, coupled to the integrating circuit, configured to generate the at least one control signal according to a window function, to adjust the integration gain of the integrating circuit, such that the integrating output signal is related to an operation result of the integrating input signal and the window function.

The disclosure provides a circuit that includes an integrator that generates an integrated signal in response to a current signal. A comparator is coupled to the integrator and receives the integrated signal and a primary reference voltage signal. The comparator generates a feedback signal. A switched capacitor network is coupled across the integrator. The feedback signal activates the switched capacitor network.

A filtering unit is presented. The filtering unit includes at least two operational amplifiers, where each of the at least two operational amplifiers includes an input end and an output end, where the input end of one operational amplifier is coupled across the corresponding input end of another operational amplifier of the at least two operational amplifiers. The filtering unit also includes a direct current link operatively coupled to the at least two operational amplifiers and at least one thermoelectric module, where each thermoelectric module includes a conducting layer, where the direct current link and at least one of the at least two operational amplifiers are operatively coupled to the at least one thermoelectric module. A filtering system is also presented.

A filtering unit is presented. The filtering unit includes at least two operational amplifiers, where each of the at least two operational amplifiers includes an input end and an output end, where the input end of one operational amplifier is coupled across the corresponding input end of another operational amplifier of the at least two operational amplifiers. The filtering unit also includes a direct current link operatively coupled to the at least two operational amplifiers and at least one thermoelectric module, where each thermoelectric module includes a conducting layer, where the direct current link and at least one of the at least two operational amplifiers are operatively coupled to the at least one thermoelectric module. A filtering system is also presented.

A circuit comprises a Sallen-Key filter, which includes a source follower that implements a unity-gain amplifier; and a programmable-gain amplifier coupled to the Sallen-Key filter. The circuit enables programmable gain via adjustment to a current mirror copying ratio in the programmable-gain amplifier, which decouples the bandwidth of the circuit from its gain settings. The programmable-gain amplifier can comprise a differential voltage-to-current converter, a current mirror pair, and programmable output gain stages. The Sallen-Key filter and at least one branch in the programmable-gain amplifier can comprise transistors arranged in identical circuit configurations.

A voltage regulator circuit having an internally compensated effective series resistance includes a control circuit to generate an out current at a regulated output voltage based on a reference voltage. The control circuit includes an amplifier, a resistive element to feedback output voltage to an input of the amplifier, and a compensation circuit to couple the internally compensated effective series resistance into the control circuit. The compensation circuit includes a first current sense device to generate a first sensed current proportional to a current through an N-type pass device, a second current sense device arranged to generate a second sensed current proportional to the current through the N-type pass device, and a bias circuit coupled to sink the first sensed current and the second sensed current to reduce a bias voltage across the resistive element below a threshold voltage.

A differential elliptic filter circuit includes: a differential amplifier, feedback and feedforward paths. An upper pair and a lower pair of inverting feedback paths couple a corresponding one the differential signal outputs of the amplifier to an inverting one of a pair of inputs of the amplifier, to provide two complex conjugate poles, and establish upper and lower virtual grounds at the amplifier inputs. Upper and lower inverting feedforward paths couple corresponding passive nodes of the upper and lower pairs of inverting feedback paths to respectively the lower and upper virtual grounds to provide two zeros of the circuit. The upper and lower non-inverting feedforward paths couple an upper and lower one of a pair of differential signal inputs of the circuit to respectively the upper and lower virtual grounds to enable positioning of the two zeros of the circuit on an imaginary axis of a pole-zero plot.

According to at least one aspect, a filter network is provided. The filter network comprises: an active filter comprising an amplifier (e.g., an operational amplifier), wherein the active filter is configured to add at least one member selected from the group consisting of a pole and a zero to a transfer function of the filter network; a passive filter coupled to the active filter and configured to add at least one pole to the transfer function of the filter network; and a non-inverting amplifier (e.g., a voltage buffer) having an input coupled to the passive filter and an output coupled to the active filter.