423results about How to "High input impedance" patented technology

A bio-electrode for detecting heart signals and the like comprises a dry electode surface having an elevated resistivity to reduce the effect of polarization noise. The electrode is combined with a circuit having an external discharge resistor across which an output signal is obtained wherein the discharge resistor has a value which reduces the time constant of polarization noise to less than one second.

A sensor arrangement (10) comprises an amplifier (11) having a signal input (12) to receive an input signal (SIN) and a signal output (13) to provide an amplified sensor signal (SOUT) that is an inverted signal with respect to the input signal (SIN). Furthermore, the sensor arrangement (10) comprises a feedback path connecting the signal output (13) to the signal input (12), wherein the feedback path comprises a series connection of a capacitive sensor (14) and a feedback capacitor (15). A voltage source arrangement (19) of the sensor arrangement (10) is connected to a feedback node (18) between the capacitive sensor (14) and the feedback capacitor (15).

A basic unit of lithium-ion battery, including: at least two series-connected lithium-ion cells; at least one lithium-ion cell for balance; controllable switches with the same number as the lithium-ion cells; a drive module for the controllable switches; a voltage detection module for detecting a voltage at two ends of the lithium-ion cells; and a controller. The lithium-ion cell for balance is connected in parallel to the lithium-ion cells. The controllable switches control the turn on/off of the connection in parallel between the lithium-ion cell for balance and each of the lithium-ion cells independently. The drive module for the controllable switches and the voltage detection module are connected to the controller. A battery pack including the basic unit of lithium-ion battery and a method for real-time charge/discharge equalizing of the basic unit of lithium-ion battery are also provided.

The invention relates to a universal data acquisition unit and a data acquisition method thereof, belonging to the technical field of data acquisition; the universal data acquisition unit comprises amicroprocessor; a multi-path discrete signal input interface is connected with the input end of a counter by a photoelectric isolating circuit, and a multi-path continuous signal input interface is connected with the input end of an A/D converter, and a microprocessor is connected with the input ends of the A/D converter and the counter. The data acquisition method comprises that: system initialization is carried out; continuous and discrete signal interrupt vector is set; interrupt latency is carried out, if the discrete signal is interrupted, the discrete signal is acquired; if the continuous signal is interrupted, the continuous signal is acquired; if a watchdog is interrupted, a system is restarted; if hibernation is interrupted, system setting data is stored, and then a hibernation state is carried out; and then, interrupt latency awaken operation is carried out, if awakening is interrupted, the system is started, and the setting is restored before interruption; if the continuoussignal and the discrete signal are acquired, interrupt latency is continuously carried out after data is transmitted to an upper computer; if not, interrupt latency is carried out directly.

The invention discloses a high-linearity broadband stacking low noise amplifier based on a gain compensation technology. The high-linearity broadband stacking low noise amplifier comprises a two-stacking low noise amplification network, an interstage matching network and a two-stacking gain expansion amplification network which are connected in sequence; and a first power supply bias network and a second power supply bias network which are connected with the two-stacking low noise amplification network and the two-stacking gain expansion amplification network. According to the high-linearity broadband stacking low noise amplifier, a serial stacking structure is realized through adoption of two transistors with different sizes and ultra wide band noise and impedance matching are realized through combination of an RLC feedback network; through utilization of the gain compression compensation technology, the gain compression property of the two-stacking low noise amplification network is cancelled within a certain bias range through the two-stacking gain expansion amplification network and a linearity index of the amplifier is improved, so the whole low noise amplifier has good broadband, linearity, low power consumption and low noise amplification capability; and moreover, the low breakdown voltage property of an integrated circuit technology is avoided and the stability and reliability of a circuit are improved.

A light transmission module has a light transmitting unit having a light emitting portion for outputting an optical signal corresponding to a data signal input as an electrical signal, and a first power supply controller for controlling a drive power supply of the light emitting portion, a light transmission path for transmitting the optical signal introduced from the light transmitting unit, a light receiving unit having a light receiving portion for receiving the optical signal output from the light transmission path and outputting an electrical signal corresponding to the optical signal, and a second power supply controller for controlling a drive power supply of the light receiving portion, and at least one electrical transmission path, connecting the light transmitting unit and the light receiving unit, for transmitting a control signal for controlling power supply to the light emitting portion and the light receiving portion to the first power supply controller and the second power supply controller. The first power supply controller and the second power supply controller control the power supply to the light emitting portion and the light receiving portion based on the control signal input via the electrical transmission path.

A combined seat heater and capacitive occupancy sensor comprises a heater network and a capacitive sensing network. The heater network includes a heating element (10) connected between a first node (21) and a second node (22) to dissipate heat. The capacitive sensing network is connected to the heating element to apply an oscillating current thereto and to derive a capacitive load of the heating element from the voltage resulting on the heating element. The heater network comprises a common mode choke (16) connecting the first and the second node to a third (23) and a fourth (24) node, respectively. The capacitive sensing network further comprises means to sustain the oscillating current in or to drive the oscillating current into the heating element as well as a high-impedance amplifier (32) having an input node operatively connected to the heating element to probe the resulting voltage, and an output node (44) to provide an output signal indicative of the voltage.

The invention relates to a solution to a working power supply and the power of a two-wire-system electronic switch, relating to the field of illuminating electronic switches. The two-wire-system electronic switch comprises an off-state electrification circuit, a switch executive circuit, an on-state electrification circuit, and the like, wherein when loads are closed, the off-state electrification circuit supplies working electric energy for the electronic switch and also eliminates the sparkling phenomenon of a load lamp; the switch executive circuit is used for executing the starting or the closing of the loads, not only has low power consumption, but also provides the switch state indication; and when the loads are started, the on-state electrification circuit provides a heavy current path for the loads and also supplies the working electric energy for the electronic switch. The invention not only solves the problem on the working power supply of the two-wire-system electronic switch, but also enhances the loading capacity of the two-wire-system electronic switch.

A method and apparatus is described for interacting with electronic devices via motional commands. The method uses perturbations of the background quasistatic electric fields. The apparatus measures perturbations in electric potential relative to the background. Body movement is recognized by comparing changes in signals in time with signals collected from training sets for specified motional commands or gestures. Upon recognizing the commands, the apparatus issues the predetermined response to the motion.

To provide a measurement device which allows long-term accurate measurement of voltage without adversely affecting a device under test, by ensuring a predetermined level of resistance to ESD and reducing leakage current. A measurement device includes a probe needle for contacting a device under test, a first FET for detecting voltage of the device under test, and a protection circuit for protecting the first FET from static electricity. The protection circuit includes a second FET having an oxide semiconductor film as a channel formation region.

A differential input comparator circuit comprises an input stage comprising dual polarity input voltages and an output stage adapted to output a differential voltage based on the input voltages, wherein the differential voltage is adapted to be transmitted to a comparator and wherein the circuit has high input impedance and works with high input voltage swings.

A power generating device is specified, which comprises a generator (1) , which is coupled to a drive unit, in particular to a turbine, and is connected via a rectifier (2) to a DC voltage intermediate circuit (3), an inverter (4), which is connected to the DC voltage intermediate circuit (3) and, on the AC voltage output side, has n phases with n AC voltage connections (5), and a filter arrangement (6), which is connected to the AC voltage connections (5). Furthermore, the filter arrangement (6) has a first filter inductance (7) and a second filter inductance (8), which is connected in series with the first, for each AC voltage connection (5), with a filter capacitor (9) being connected to the junction point of the first filter inductance (7) and the second filter inductance (8), and the filter capacitors (9) being connected to one another in a star circuit at a star point (10).

A broadband RF signal amplifier includes a plurality of transistors attached to a surface of a pedestal, each transistor having an input and an output. An RF input path electrically connected to the transistor inputs includes a passive splitter implemented in a multi-layer printed circuit board and configured to split a RF input signal into a plurality of component input signals. A plurality of corresponding input matching networks including one-quarter wavelength transmission lines implemented in the printed circuit board couple respective component input signals to the transistor inputs at an input impedance, the input matching networks further comprising respective input matching capacitors attached to the pedestal. An RF output path electrically connected to the transistor outputs includes a passive combiner implemented in the printed circuit board and configured to combine component output signals received at the transistor outputs into a RF output signal. A plurality of corresponding output matching networks including one-quarter wavelength transmission lines implemented in the printed circuit board couple the respective component output signals at the transistor outputs to an output impedance.

The invention relates to animal muscle diagnosis and human body bioelectricity acquisition and recognition. The invention relates to electrode conductors for collecting surface electromyography signals, a functional buffer stage circuit, a preposing differential amplifying circuit, a filter circuit, a double T trap circuit and a back-stage amplifying circuit; the preposing differential amplifying circuit comprises a preceding stage differential amplifying circuit and a secondary differential amplifying circuit; the output end of the preceding stage differential amplifying circuit is also connected with a voltage follower circuit and an inverse amplifying feedback circuit which is communicated with the voltage follower circuit; the output of the inverse amplifying feedback circuit is communicated with the root of the electrode conductor; the filter circuit is the fifth-order Butterworth filter circuit; the electrode conductors are two silver electrodes which are pasted on the surface of skin; and the distance between the two silver electrodes is 8-12mm. The active double electrode surface electromyography sensor has good fixed mode, stable collected signals and strong signal filtering function, causes the capability of the circuit resisting the interfering of the power frequency to be increased and overcomes the defects of the high noise brought about by the electrode wiring, larger whole volume of the sensor and the like.

A front end circuit for coupling an antenna to a radio frequency (RF) transceiver is disclosed. An antenna port connectible to the antenna is provided, as well as a power amplifier coupled to a signal output of the RF transceiver and a low noise amplifier coupled to the signal input of the RF transceiver. The front end circuit includes a switching network that is connected to the antenna port, the power amplifier, and the low noise amplifier. Additionally, there is at least one resonant circuit and a control circuit coupled to a receive enable line of the transceiver. This resonant circuit defines a parallel resonance with a first resonant resistance in the operating frequency band upon activation in the receive mode. The resonant circuit also defines a substantially high transistor impedance upon deactivation in the transmit mode.

System and method for providing isolated power to a component that is also subject a set of RF signals that includes at least a first RF signal having a first RF frequency is provided. There is included providing a DC voltage signal and modulating the DC voltage signal into an isolated power signal using an isolation transformer. The isolated power signal has an intermediate frequency that is higher than 60 Hz and lower than the first RF frequency. There is included supplying the DC voltage signal to the primary winding and obtaining the isolated power signal from the secondary winding; and delivering the isolated power to the component using the isolated power signal.

The invention discloses a chopping amplifying circuit. A differential signal is connected to a circuit from a differential input end, and the differential input end is connected with an input end of a first-grade chopping switch; an output signal of the first-grade chopping switch is connected to the same-phase input ends of two differential operation amplifiers of a first-grade amplification circuit, and output ends of two differential operation amplifiers in the first-grade amplification circuit are connected to an input end of a second-grade chopping switch; an output signal of the second-grade chopping switch is connected to the same-phase and reverse-phase input ends of a second-grade amplification circuit; an output end of the second-grade amplification circuit is connected with input ends of a low pass filtering circuit and a negative feedback loop chopping switch, the other input end of the negative feedback loop chopping switch is connected with a common mode voltage; an output signal of the negative feedback loop chopping switch is connected to reverse-phase input ends of the two differential operation amplifiers in the first-grade amplification circuit after passing through pressure differential of a feedback network, and the low-pass filter wave circuit outputs a final amplifying signal of the chopping amplifying circuit.

A microwave amplifier device with a bypass segment, the device operating either in active mode or in bypass mode. The bypass segment (2) comprises at least one section (13) of coupled transmission lines (14,15) whereby the isolation is increased. The amplifier unit (1) includes two LNAs arranged in parallel in a balanced configuration, and the bypass segment (2) has a relatively high input impedance in active mode, whereby a balanced operation of the amplifier unit is maintained. Consequently, a low noise factor is obtained, as well as reduced input and output reflections.

A Sallen-Key filter requires an operational amplifier with a large input impedance and a small output impedance to meet the external filter characteristics. The operational amplifier requires an internal feedback path for stability that limits performance. This invention eliminates the need for internal feedback and increases the gain of a source follower which has characteristics matching the operational amplifier in the Sallen-Key filter. The source follower provides 6 dB of AC voltage gain and is substituted for the operational amplifier in the Sallen-Key filter. The Sallen-Key filter requires a differential configuration to generate all the required signals with their compliments and uses these signals in a feed forward path. Furthermore, since the source follower uses only two n-channel stacked devices, the headroom voltage is maximized to several hundred millivolts for a 1.2V voltage supply in a 40 nm CMOS technology. Thus, the required 880 MHz bandwidth of the Sallen-Key filter can be easily met using the innovative source follower.