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.

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. In a preferred form, the TANK filter reduces or even eliminates the use of ferro-magnetic materials, and instead uses non-ferromagnetic materials so as to reduce or eliminate MRI image artifacts or the force or torque otherwise associated during an MRI image scan.

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. A passageway through the tank filter permits selective slidable passage of a guide wire therethrough for locating the lead wire in an implantable position. 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.

A TANK filter is provided for a lead wire of an active medical device (AMD). In a preferred form, the TANK filter is integrated into a TIP and / or RING electrode for an active implantable medical device. 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 to attenuate current flow through the lead wire along a range of selected frequencies. In a particularly preferred form, the TANK filter is manufactured using very low k materials of sufficient strength to handle forces applied thereto during installation and use.

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. A passageway through the tank filter permits selective slidable passage of a guide wire therethrough for locating the lead wire in an implantable position. 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.

A TANK filter is provided for a lead wire of an active medical device (AMD). In a preferred form, the TANK filter is integrated into a TIP and / or RING electrode for an active implantable medical device. 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 to attenuate current flow through the lead wire along a range of selected frequencies. In a particularly preferred form, the TANK filter is manufactured using very low k materials of sufficient strength to handle forces applied thereto during installation and use.

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 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. In a preferred form, the TANK filter reduces or even eliminates the use of ferro-magnetic materials, and instead uses non-ferromagnetic materials so as to reduce or eliminate MRI image artifacts or the force or torque otherwise associated during an MRI image scan.

Provided are a wireless power transmission receiver and a system including the same, particularly to a receiver and transmitter transmitting power from one transmitter to a plurality of receivers at the same time by wireless. According to the present invention, the wireless power receiver comprises a receiving coil unit receiving power from a transmitter by a resonance coupling method; and a power receiving unit receiving power from the receiving coil unit to provide the power to a load resistor, wherein an input impedance of the power receiving unit is adjusted according to power consumed by a plurality of receivers. Therefore, power transmission efficiency of the wireless power receiver and transmitter can be improved.

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.

A differential to single-ended signal transfer circuit that allows increased gain and improved AC performance while reducing power supply voltage requirements. The transfer circuit includes a first operational transconductance amplifier (OTA), a second operational amplifier (OPA), first and second controlled current sources, a third current source, and first and second bipolar junction transistors. The inverting and non-inverting inputs of the transfer circuit are provided at the inverting input and the non-inverting input, respectively, of the OTA, which is coupled to the first and second controlled current sources to form a current mirror with tracking feedback. The output voltage of the transfer circuit is provided at the emitter of the first transistor, the base of which is connected to the non-inverting input INp. The first transistor is coupled to the third current source in an emitter follower configuration to provide both current gain and impedance matching. The base of the second transistor is connected to the inverting input of the transfer circuit. The OPA is coupled between the respective emitters of the first and second transistors in a voltage follower configuration.

An electrostatic capacitance detection circuit 10 comprises a DC voltage generator 11, an operational amplifier 14 of which non-inverting input terminal is connected to specific potential, an impedance converter 16, a resistance (R1) 12 connected between the DC voltage generator 11 and an inverting input terminal of the operational amplifier 14, a resistance (R2) 13 connected between the inverting input terminal of the operational amplifier 14 and an output terminal of the impedance converter 16, and a capacitor 15 connected between an output terminal of the operational amplifier 14 and an input terminal of the impedance converter 16. A capacitor to be detected 17 is connected between the input terminal of the impedance converter 16 and specific potential.

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.

An instrumentation amplifier that includes input capacitance cancellation is provided. The architecture includes programmable capacitors between the input stage and a current feedback loop of the instrumentation amplifier to cancel input capacitances from electrode cables and a printed circuit board at the front end. An on-chip calibration unit can be employed to calibrate the programmable capacitors and improve the input impedance.

A low noise amplifier having a wide operating frequency band and a high dynamic range is provided. A transformer having a secondary winding connected between an input terminal to which an input signal is applied and a positive differential output terminal, and a primary winding connected between a negative differential output terminal and an input node is provided as a feedback circuit between a cascode amplifier circuit, which includes transistors and a resistor, and an output circuit, which includes a transistor and a constant current source. Selective use of a transformer whose leakage inductance has an adequate value as the feedback transformer can realize a low noise amplifier which has a wide operating frequency band and a high dynamic range.

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.

A low noise amplifier having a wide operating frequency band and a high dynamic range is provided. A transformer having a secondary winding connected between an input terminal to which an input signal is applied and a positive differential output terminal, and a primary winding connected between a negative differential output terminal and an input node is provided as a feedback circuit between a cascode amplifier circuit, which includes transistors and a resistor, and an output circuit, which includes a transistor and a constant current source. Selective use of a transformer whose leakage inductance has an adequate value as the feedback transformer can realize a low noise amplifier which has a wide operating frequency band and a high dynamic range.

In a constant current circuit, a constant current is caused to flow through a resistor, thereby causing a constant voltage to occur across the resistor. This constant voltage is then superimposed on an output signal of an operational amplifier that is to be fed back to the drain of a field effect transistor, thereby maintaining the same potential in an AC manner between the output terminal of the operational amplifier and the drain of the field effect transistor. In this way, the gate and drain of the field effect transistor is caused to exhibit the same potential in an AC manner, so that no current will occur through the stray capacitance between the gate and drain of the field effect transistor. As a result, similarly to a case of using a feedback capacitor, the input impedance of the field effect transistor can be raised.

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 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.

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.

A control circuit is provided to generate a mode signal at light load of the power converter. The mode signal is coupled to disable the switching signal for saving power. The impedance of an input circuit is increased in response to the mode signal. Furthermore, a soft start circuit is initiated by the mode signal when switching signal is enabled. An external capacitor associates with the impedance of the input circuit determine the off period of the switching signal.