69results about How to "Improve input impedance" patented technology

A TANK filter is provided for a lead wire of an active medical device (AMD). The TANK filter includes a capacitor in parallel with an inductor. The parallel capacitor and inductor are placed in series with the lead wire of the AMD, wherein values of capacitance and inductance are selected such that the TANK filter is resonant at a selected frequency. The Q of the inductor may be relatively maximized and the Q of the capacitor may be relatively minimized to reduce the overall Q of the TANK filter to attenuate current flow through the lead wire along a range of selected frequencies. In a preferred form, the TANK filter is integrated into a TIP and/or RING electrode for an active implantable medical device.

There is disclosed an improved differential amplifier (20) having a feedback loop that generates an amplified output signal (Vout) from an input signal (Vin) supplied by a preceding stage. It comprises an input matching circuit (11) connected to said preceding stage, a buffer (22) and an amplification section (12) connected in series in the direct amplification line, a first amplifier (16), a RC network (17′) and a second amplifier (23) connected in series in a parallel loop between the outputs and the inputs of the amplification section that generate the feedback signal. The role of said buffer and second amplifier associated in a dedicated direct and feedback signal combining block (21) is to respectively isolate the input signal and the feedback signal from the summing nodes (A′,B′) at the amplification section inputs. As a result, the summation of the input signal and the feedback signal is improved, the DC component of the output signal is filtered out in order to significantly reduce the DC offset. In addition, the input impedance matching represented by parameter S₁₁ is considerably improved.

A sample and hold circuit including a sampling capacitor for storing a sample of an input signal, an output stage for outputting the sample stored on the sampling capacitor; and input circuitry for sampling the input signal and storing the sample on the sampling capacitor. The input circuitry includes an autozeroing input buffer which selectively samples the input signal during a first operating phase and holds a sample of the input signal during a second operating phase. The autozeroing input buffer cancels any offset error. The input circuitry also includes switching circuitry for selectively coupling the sampling capacitor with an input of the sample and hold circuitry during the second operating phase and to an output of the autozeroing input buffer during the first operating phase.

A radio frequency front-end receiver includes a single stage low noise amplifier connected with a resistor array and a capacitor array, and a Gilbert-type mixer connected with a PMOS transconductance stage, an inductor and a serially connected current source. The resistor array enables the adjustment of the power gain of the low noise amplifier. The capacitor array tunes the low noise amplifier so that the maximum power gain is at the desired operating frequency. The PMOS transconductance stage reduces the power consumption of the mixer. The inductor increases the impedance and the current source improves the common-mode rejection of the mixer.

A TANK filter is provided for a lead wire of an active medical device (AMD). The TANK filter includes a capacitor in parallel with an inductor. The parallel capacitor and inductor are placed in series with the lead wire of the AMD, wherein values of capacitance and inductance are selected such that the TANK filter is resonant at a selected frequency. The Q of the inductor may be relatively maximized and the Q of the capacitor may be relatively minimized to reduce the overall Q of the TANK filter to attenuate current flow through the lead wire along a range of selected frequencies. In a preferred form, the TANK filter is integrated into a TIP and/or RING electrode for an active implantable medical device.

The invention relates to a combined near field communication and wireless power transmitter device comprising a first antenna coupled to antenna tuning network and capable of coupling to one or more second antennae in the near field of the first antenna with coupling characteristics, means for communicating wirelessly using said first antenna with a near field communication device in a near field communication mode, and means for transmitting wirelessly power using said first antenna to another device in the vicinity of the first antenna in a power transmission mode. In power transmission mode, the antenna tuning network operates in resonance and has an initial input impedance which is configured to change if there is a change in the coupling characteristics during power transmission, for example charging. The invention also relates to a method of transmitting power to a mobile device for example for charging purposes.

A planar microstrip antenna includes one or more aperture-fed circular patch radiating elements capacitively coupled to respective parasitic strip elements. The circular patches are symmetrically disposed above respective ground plane apertures, and the parasitic strip elements are annular sectors that are co-planar and concentric with the circular patches, and placed adjacent to the periphery of each circular patch. The disclosed geometry enhances the input impedance bandwidth, and significantly reduces off-boresight radiation variability to provide beam directivity that is more uniform over both frequency and direction.

A DSM variable high-gain circuit includes a differential amplifier and a negative feedback loop comprising low resistance poly resistors and switches configured in a T-structure having a junction point as part of the negative feedback loop. A third resistor branch of the T-structure includes a switch that connects the junction point through the third resistor branch to ground when in a closed state and that turns the third resistor branch into an open circuit when in an open state The switch of the third resistor branch, when in the closed state, produces a gain at the output of the variable high-gain circuit.

An antenna apparatus for a mobile terminal is provided. The antenna apparatus includes an antenna pattern, a first electric circuit and a second electric circuit respectively connected between both ends of the antenna pattern and a system ground, and a third electric circuit disposed between the antenna pattern and a feeding line, wherein the first electric circuit and the second electric circuit extend electrical wavelengths of the antenna pattern and the third electric circuit increases input impedance matching.

The invention provides an ultra-wideband MIMO antenna. The ultra-wideband MIMO antenna comprises four antenna array elements with the same structure, and each array element is fed separately; positions of adjacent array elements are mutually vertical and are isolated through a rectangular slot, and the tail ends of the rectangular slots are electrically connected at the center position of the MIMOantenna; each antenna array element comprises a grounding plate, a feeding unit and a parasitic patch which are printed on the surface of an antenna dielectric plate respectively; an elliptical areais also cut off on the grounding plate; the feeding unit uses elliptical and rectangular areas and digs out an elliptical area as feeding parts of the antenna; and due to the coupling effects in the above mode, on one hand, high isolation is acquired among unit, and on the other hand, while the antenna acquires the ultra-wideband characteristic, the antenna has the advantages of miniaturization and compact structure and the like.

A receiver (100) for a three-wire digital interface, comprises a first resistive element (R1) coupled between a first input terminal (A) and a first junction node (JA), a second resistive element (R2) coupled between a second input terminal (B) and a second junction node (JB), and a third resistive element (R3) coupled between a third input terminal (C) and a third junction node (JC). A network (70) comprising first second and third network terminals (71, 72, 73) is coupled to, respectively, first, second and third junction nodes (JA, JB, JC). The network has substantially the same impedance between all pairs of the first, second and third network terminals. A first comparator (C1) has a non-inverting input (10) coupled to the first input terminal (A), an inverting input (12) coupled to the second junction node (JB), and an output (14) coupled to a first output terminal (AJ). A second comparator (C2) has a non-inverting input (20) coupled to the AK first input terminal (A), an inverting input (22) coupled to the third junction node (JC), and an output (24) coupled to a second output terminal (AK). A third comparator (C3) has a non-inverting input (30) coupled to the second input terminal (B), an inverting input (32) coupled to the third junction node (JC), and an output (34) coupled to a third output terminal (BJ). A fourth comparator (C4) has a non-inverting input (40) coupled to the second input terminal (B), an inverting input (42) coupled to the first junction node (JA), and an output (44) coupled to a fourth output terminal (BK). A fifth comparator (C5) has a non-inverting input (50) coupled to the third input terminal (C), an inverting input (52) coupled to the first junction node (JA), and an output (54) coupled to a fifth output terminal (CJ). A sixth comparator (C6) has a non-inverting input (60) coupled to the third input terminal (C), an inverting input (62) coupled to the second junction node (JB), and an N output (64) coupled to a sixth output terminal (CK).

A header block is configured to be attachable to an implantable medical device. The header block includes a header block body and a connection port disposed in the header block body configured to receive an implantable lead. A conductor is disposed in the header block body electrically coupled to the connection port at a first end and connectable at a second end to the implantable medical device. An impeding device is electrically coupled in series along the length of the conductor and disposed within the header block body. The impeding device is configured to raise the high-frequency impedance of the conductor. The impeding device may include a bandstop filter or an L-C tank circuit.

A TANK filter is provided for a lead wire of an active medical device (AMD). The TANK filter includes a capacitor in parallel with an inductor. The parallel capacitor and inductor are placed in series with the lead wire of the AMD, wherein values of capacitance and inductance are selected such that the TANK filter is resonant at a selected frequency. The Q of the inductor may be relatively maximized and the Q of the capacitor may be relatively minimized to reduce the overall Q of the TANK filter to attenuate current flow through the lead wire along a range of selected frequencies. In a preferred form, the TANK filter is integrated into a TIP and/or RING electrode for an active implantable medical device.