Balun

About: Balun is a research topic. Over the lifetime, 5375 publications have been published within this topic receiving 52256 citations. The topic is also known as: Telephone balance unit.

Wideband, planar, log-periodic balun

Abstract: This paper presents the design and performance characteristics of a new planar balun structure. The design is based on the log-periodic antenna theory. The design guidelines, as well as simulated and measured results are presented. It is shown that the new balun has greater than one octave bandwidth. The log-periodic balun will find applications in wireless communication circuits such as mixers, amplifiers and antennas.

Study of a New Planar-Type Balun Topology for Application in the Design of Balun Bandpass Filters

Abstract: A comprehensive study of a new planar-type balun prototype is presented in this paper for application in the design of balun bandpass filters (BPFs) with widely used open-type resonators. The proposed balun is in general composed of two identical back-to-back quarter-wavelength ( $\lambda $ /4) coupled line sections. The design concept originates from the analysis of the standing wave pattern on a half-wavelength ( $\lambda $ /2) open-circuited transmission line. After an intuitive illustration is given, its working principle is presented to validate the feasibility of the proposed balun. Afterward, two types of the coupled line prototypes are analyzed to implement the proposed balun with filtering response, whereas a basic rule is given to realize the transmission zeros. To further demonstrate the validity of the proposed balun prototype, two practical balun BPFs with common dual-mode resonators are designed and fabricated. As expected, transmission zeros are generated near the desired passband of our presented balun filters, thereby improving their frequency selectivity. Both simulated and measured results exhibit good filtering and balun performance.

Transformers, balanced-unbalanced transformers (baluns) and integrated circuits including the same

Abstract: A transformer of fully symmetric structure includes a primary coil assembly and a secondary coil assembly. The primary coil assembly includes a plurality of primary coils formed in a plurality of metal layers, and a first interlayer connection unit for connecting the primary coils. The secondary coil assembly includes a plurality of secondary coils formed in the plurality of metal layers, and a second interlayer connection unit for connecting the secondary coils. The primary and secondary coils formed in the same metal layer are concentric and axisymmetric with respect to a diameter line passing through a planar center point. A balanced-unbalanced transformer (balun) is a type of transformer that may be used to convert an unbalanced signal to a balanced one or vice versa. An integrated circuit may include a semiconductor substrate and a transformer. Electrical elements such as transistors may be formed on the semiconductor substrate.

A 76–84 GHz SiGe Power Amplifier Array Employing Low-Loss Four-Way Differential Combining Transformer

Abstract: This paper presents holistic design of a novel four-way differential power-combining transformer for use in millimeter-wave power-amplifier (PA). The combiner with an inner radius of 25 μm exhibits a record low insertion loss of 1.25 dB at 83.5 GHz. It is designed to simultaneously act as a balanced-to-unbalanced converter, removing the need for additional BALUNs typically required in differential circuits. A complete circuit comprised of a power splitter, two-stage differential cascode PA array, a power combiner as well as input and output matching elements was designed and realized in SiGe technology with fT/fmax 170/250 GHz. Measured small-signal gain of at least 16.8 dB was obtained from 76.4 to 85.3 GHz with a peak 19.5 dB at 83 GHz. The prototype delivered 12.5 dBm output referred 1 dB compression point and 14 dBm saturated output power when operated from a 3.2 V dc supply voltage at 78 GHz.

A Fully Differential 77-GHz Active IQ Modulator in a Silicon-Germanium Technology

Abstract: A 77-GHz IQ modulator in a fully differential circuit configuration is presented. It includes an local oscillation (LO) buffer amplifier, a medium-power output stage, a double-balanced active mixer architecture and on-chip baluns for easy characterization. A differential branch-line coupler provides quadrature phase signals at the upconversion mixer LO inputs. The circuit is manufactured in a 200-GHz transit frequency technology, and the circuit performance is shown by on-wafer measurements.