Electronic filter

About: Electronic filter is a research topic. Over the lifetime, 13207 publications have been published within this topic receiving 93063 citations. The topic is also known as: filter.

0.5 V sixth-order Chebyshev band-pass filter based on multiple-input bulk-driven OTA

Abstract: This paper presents a low-voltage sixth-order Chebyshev band-pass filter based on multiple-input operational transconductance amplifier (MI-OTA). The used voltage supply is 0.5 V and the filter employs six MI-OTAs and six capacitors. The third intermodulation distortion (3rd IMD) is below 1% for input sine wave signal with peak-to-peak up to rail-to-rail while the dynamic range (DR) is 66.8 dB. In order to insure low-voltage operation capability, extended linear range, increased voltage gain of the MI-OTA, the multiple-input bulk-driven transistor (MIBD) along with self-cascode techniques have been used. As a result, the proposed MI-OTA based on MIBD is capable to work with 0.5 V supply voltage and consumes power in the range of (2.5–1.2E3) nW for tunable bias current in the range from 1 nA to 500 nA. The MI-OTA and the filter circuits were designed and simulated in Cadence/Spectre environment using 0.18 µm CMOS process from TSMC. The simulation results agree well with theory and confirm the filter functionality.

High-Performance, Compact Quasi-Elliptic Band Pass Filters for V-Band High Data Rate Radios

Abstract: This paper presents a comparison of the design and implementation of V-band quasi-elliptic band pass filters suitable for system-on-package integration at millimetre-wave frequencies. Filters were designed and manufactured at low-temperature co-fired ceramic (LTCC) and alumina substrates. Filter circuits include the input/output coplanar waveguide to microstrip transitions as well as the microwave pads, used to facilitate measurement. Three four-pole filters incorporating half-wavelength resonators were implemented, two planar (on LTCC and alumina substrates) and one vertically stacked (on LTCC). In addition a six-pole filter was also implemented in alumina. The four-pole LTCC based filters have a measured insertion loss (IL) as low as 3.4 dB, fractional bandwidth (FBW(%) = BW-3 dB/Center Frequency) of 4.8% and return loss better than 10 dB. Total filter size is less than 1.1 × 0.74 mm. The alumina-based four-pole/six-pole filters exhibit a measured IL of 2.8/3.1 dB, FBW of 8.3%/12.6%, respectively. Both alumina filters exhibit a return loss better than 10 dB and with a corresponding filter layout footprint of less than 1.01 × 1.34 mm. A new figure-of-merit (HPFOM) is proposed and results from the filters proposed here clearly show they offer the best trade-off between performance and area (higher HPFOM).

New inverter output filter topology for PWM motor drives

Abstract: This paper presents a new inverter output filter topology for PWM motor drives. It is shown that the proposed filter effectively reduces high frequency harmonics which cause serious damage to the motor bearings and insulation. The proposed filter is comprised of a conventional RLC network cascaded with an LC trap filter. The LC trap, tuned to the inverter switching frequency is very effective in reducing the switching harmonics. By using this new topology the need for high damping resistance and low RLC cut-off frequency is eliminated. This reduces the phase shift in the current regulation loop and increases the filter efficiency. Experimental verification of the filter topology is provided with a 480 V inverter and a 25 HP permanent magnet synchronous motor. Space-vector predictive current regulation is implemented as an inner-loop current regulator for the outer-loop speed control using a digital signal processor. The effectiveness of the filter at different motor speeds is presented.

Switch power supply equipment

Abstract: The switching power unit is a switching power unit of PWM system in which, in response to a secondary-side output voltage detected by an output voltage detecting circuit, a control circuit controls a duty of a main switching element so as to stabilize the output voltage. There is provided a filter circuit, preventing EMI, which is constituted of filter capacitors and a filter coil. In relation to the filter circuit, there is provided a discharging resistor which is constituted of two series resistors so as to prevent an accident by discharging electric charges of the filter capacitors quickly. A voltage of a connection point between the series resistors is applied to a power supplying capacitor of the control circuit via an activating resistor. Thus, when a power source is turned on, an activating current is supplied from a voltage whose value is ½ with respect to a root means square value of a rough input ac voltage, so that it is possible to reduce a loss in an activating circuit which activates the control circuit.

High-frequency high-voltage switching power supply for electric precipitation

Abstract: The invention relates to a high-frequency high-voltage switching power supply for electric precipitation. Three-phase alternating-current is input and converted into direct current by a three-phase rectifier filter circuit and then the direct current passes through a high-frequency inverter circuit; a series-parallel connection resonant soft switching circuit is connected between two inverter bridge arms in the high-frequency inverter circuit; the output of the series-parallel connection resonant soft switching circuit is boosted by a high-frequency pulse transformer, the boosted output passes through a high voltage silicon rectifier stack to form high-voltage direct current and the high-voltage direct current is input into an electric precipitator; a DSP controller outputs a control signal to the high-frequency inverter circuit; the input side of the electric precipitator is connected with a voltage and current detection circuit; the detection circuit detects voltage and current and inputs a signal into the DSP controller; the high-frequency inverter circuit is adjusted by the DSP controller; and the DSP controller is connected with an upper computer through a CAN interface so asto realize optimal control. The switching power supply is used for electric precipitation equipment and has the advantages of small volume, light weight, light harmonic pollution, high power factor, high conversion efficiency, and capability of generating waveforms meeting various working condition requirements of the electric precipitation equipment so as to realize energy conservation and emission reduction.