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.

A Wideband, Dual-Path, Millimeter-Wave Power Amplifier With 20 dBm Output Power and PAE Above 15% in 130 nm SiGe-BiCMOS

Abstract: A frequency-scalable, three-stage, transformer-coupled millimeter-wave power amplifier (PA) is implemented in 130 nm SiGe-BiCMOS. Differential common-base gain stages extend collector-emitter breakdown voltage beyond 3 V, while collector-emitter neutralization increases reverse isolation and stability. Monolithic self-shielded transformers designed for low insertion loss and compact dimensions on-chip include: a 2:4 input power splitter, a 4:1 output balun combiner and inter-stage coupling transformers. The balun combiner and fully-differential splitter are compensated for imbalances caused by parasitic interwinding capacitance, and simulations predict better than 3% uniformity between reflected port-to-port impedances at 60 GHz. Simulated impedance uniformity is within 6% from 55-65 GHz, and insertion loss of the 0.015 mm2 combiner prototypes at 60 GHz is below 1 dB. The 0.72 mm2 60 GHz-band PA realizes a measured peak small-signal gain higher than 20 dB with over 10 GHz 3 dB bandwidth. Reverse isolation is better than 51 dB from 50-65 GHz and the PA is unconditionally stable. It consumes 353 mW (quiescent) from a 1.8 V supply and the active area is 0.25 mm2. Maximum output power and peak power-added efficiency (PAE) are 20.1 dBm and 18% at 62 GHz, respectively. An up-banded 79-87.5 GHz PA is also implemented to verify frequency scalability of the design. The 0.23 mm2 active area 79 GHz PA prototype produces 18 dBm saturated output power and 9% peak-PAE at 84 GHz from a 2.5 V supply.

Review of printed Marchand and double Y baluns: characteristics and application

Abstract: A review of printed baluns is presented. This is divided into two main groups; Marchand baluns (band pass networks) and double Y baluns (all pass networks). For each of these groups of baluns, three different realizations are given: microstrip-slot line, CPW-slot line and CPW/sub FGP/-CPS and their theoretical and experimental characteristics are compared. Simple expressions for the design of Marchand baluns with Chebyshev response, which replace the complicated synthesis proposed by Cloete are derived. Superior broadbandwidth features of double Y baluns are demonstrated in the design of two uniplanar double balanced mixers. Both the double Y mixer and the CPW/sub FGP/-CPS mixer have a frequency bandwidth 1:6, whilst maintaining other performance similar to that achieved with classical double balanced mixers. >

A Subharmonic Graphene FET Mixer

Abstract: We demonstrate a subharmonic resistive graphene FET mixer utilizing the symmetrical channel-resistance versus gate-voltage characteristic. A down-conversion loss of 24 dB is obtained with fRF = 2 GHz, fLO= 1.01 GHz, and fIF= 20 MHz in a 50- Ω-impedance system. Unlike conventional subharmonic resistive FET mixers, this type of mixer operates with only one transistor and does not need any balun at the local oscillator (LO) port, which makes it more compact.

Linear RF power amplifier

Abstract: A linear RF power amplifier employs push-pull pairs of high voltage mosfets. A minimum of transformers is employed, with an impedance matching transformer feeding an input balun supplying the input signal in push-pull to the gates of the mosfets. The drains are coupled to balanced legs of an output balun, followed by an output impedance matching transformer. Thermal sensors are employed for control of gate bias and also for control of drain voltage. The temperature sensors are mounted in the air inlet path and on the spreader plate of the heat sink. An aluminum or fiberglass strap is used to press the transistors against the spreader plate thereby ensuring good thermal contact with the transistor dies.