Miniaturised integrated passive device balun design with balanced amplitude and phase for Wi‐Fi applications
■A miniaturised integrated passive device (IPD) balun design with low insertion loss and balanced amplitude and phase is proposed for Wi‐Fi/Bluetooth applications. In this design, a novel topology based on the modified T‐type filter structure is introduced to offset the parasitic and coupling effects that cause poor balance in IPD design. The proposed balun design is fabricated on a GaAs substrate. The measured insertion loss is lower than 0.9 dB and the measured return loss is >16 dB in the frequency range of 2.2–2.9 GHz. The measured results of amplitude and phase show rather minor imbalances, which are lower than ±0.67 dB and ±1.8° respectively. The fabricated device size is 0.9 mm × 0.6 mm only.
●KEYWORDS
■baluns, filters
●INTRODUCTION
■With the rapid development of mobile communications, it makes a strong requirement for electronic devices to be compact, lightweight, multi‐functional, and high performance.As a result, the system in package (SIP) technology, as an important technical route beyond Moore's Law at the integrated packaging level, has received more and more attention and applications. An integrated passive device (IPD) has recently been widely used and became an important puzzle for implementing SIP. In the literature, IPD has been used to realise microwave components like bandpass filters, power dividers,baluns and etc.
■Baluns are the key passive devices in balanced microwave front‐end circuits such as balanced mixers, antenna feed networks and push‐pull amplifier. Baluns convert signal from unbalance to balance with half of the input signal amplitude and the phase delay difference of 180° at two out terminals.Usually, passive baluns are classified by lumped‐element baluns, Marchand baluns, and transformer baluns. The widely used distributed structure is more suitable for high frequency band (>4 GHz), such as Marchand baluns.However, at low frequencies distributed structure consumes too much of the expensive chip area and are therefore not suitable for MMICs. In this case, lumped‐element baluns exampled by a second‐order lattice type composed of T‐junction low/high‐pass filters were candidates for IPD circuit. But for chip‐level design, the parasitic effects of lumped circuit devices and the coupling effects between them had an influence on the performance. Chen et al. addressed on the theory of second‐order lattice type balun by ABCD matrix arrangement results for inductor and capacitor's value calculated accurately. Kumar et al. used the traditional T‐filter structure balun as an example, the results of the parasitic effect calculation are discussed.
■In this letter, a miniaturised GaAs‐based IPD balun design with low insertion loss and balanced amplitude and phase is proposed. In this design, a novel topology based on the modified T‐type filter structure is introduced to offset the parasitic and coupling effects that cause poor balance. In the following sections, the proposed balun design using the modified T‐junction network is analysed. The simulation results from the electromagnetic (EM) simulator UltraEM as well as the measured results are included to illustrate and validate the effectiveness of the proposed design.
|
Technical Documentation |
|
|
|
|
Please see the document for details |
|
|
|
|
|
|
|
|
SIP |
|
|
English Chinese Chinese and English Japanese |
|
|
22 July 2023 |
|
|
|
|
|
|
|
|
1.4 MB |
- +1 Like
- Add to Favorites
Recommend
All reproduced articles on this site are for the purpose of conveying more information and clearly indicate the source. If media or individuals who do not want to be reproduced can contact us, which will be deleted.
Integrated Circuits
Discrete Components
Connectors & Structural Components
Assembly UnitModules & Accessories
Power Supplies & Power Modules
Electronic Materials
Instrumentation & Test Kit
Electrical Tools & Materials
Mechatronics
Processing & Customization
