Journal of IKEEE (전기전자학회논문지)

Institute of Korean Electrical and Electronics Engineers (한국전기전자학회)
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LTCC-based transformer design for output stage of differential RF power amplifiers

차동 전력증폭기 출력단용 LTCC 기반 RF 트랜스포머 설계

  • Jewook Woo (Department of Electronic Engineering, Gangneung-Wonju National University) ;
  • Heesu Kim (Department of Electronic Engineering, Gangneung-Wonju National University) ;
  • Jooyoung Jeon (Department of Electronic Engineering, Gangneung-Wonju National University)
  • 우제욱 ;
  • 김희수 ;
  • 전주영
  • Received : 2023.02.22
  • Accepted : 2023.03.13
  • Published : 2023.03.31
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Abstract

In this paper, a Radio Frequency (RF) transformer (TF) based on LTCC (Low Temperature Co-fired Ceramic) for the output stage of differential power amplifiers is presented. Instead of using an usual L-C matching circuit, a small-sized transformer was implemented on the LTCC board and the results were verified through simulation. For reduced size and better performance, a TF using more metal layers was implemented and compared with the existing TF through simulation. As a result of comparison, the proposed TF has an area reduced by 55% and a coupling coefficient increased by 25%, and insertion loss improvement of about 0.4dB at 5GHz was confirmed.

본 논문에서는 차동 전력증폭기 출력단에서의 전력 결합 및 임피던스 정합을 위한 LTCC 기반의 RF 트랜스포머를 제시하였다. 기존의 인덕터와 커패시터를 이용한 정합회로 대신 회로의 면적을 덜 차지하며 직류 차단의 역할을 수행하는 트랜스포머를 LTCC 기판에 구현하고 시뮬레이션을 통해 결과를 검증하였다. 트랜스포머의 다운사이징과 결합계수의 개선을 위해 기판의 더 많은 금속층을 사용하는 트랜스포머를 구현하고 시뮬레이션을 통해 기존의 트랜스포머와 성능을 비교하였다. 3개의 금속층을 사용한 기존의 트랜스포머와 5개의 금속층을 사용한 변형된 트랜스포머를 비교한 결과 새롭게 제시한 트랜스포머가 55% 감소된 면적과 25% 증가한 결합계수를 가지며 5GHz에서 약 0.4dB의 삽입손실 개선을 확인하였다.

Keywords

Acknowledgement

This study was supported by "2021 Academic Research Support Program in Gangneung-Wonju National University" and "Regional Innovation Strategy (RIS)" through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(MOE)(2022RIS-005).

References

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