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Analysis of Problems when Generating Negative Power for IT devices

IT 기기의 마이너스 전원 생성 시 문제점에 관한 분석

  • Received : 2020.11.30
  • Accepted : 2020.12.21
  • Published : 2020.12.31

Abstract

In this paper, the problem that occurs when negative voltage is generated using an inexpensive buck device in an IT device that is supplied with a single power by an adapter or battery is analyzed. For the cause analysis, the principle of operation of the buck device and the principle of the inverter circuit were examined, and the circuit characteristics of the inverter circuit were analyzed using the buck device. As a result of the analysis, it was confirmed that the inverter circuit using the buck device initially needs a large starting current, and in particular, in the case of a current capacity that is less than the starting current in the circuit that supplies power, it was confirmed that it could fall into a state similar to the latch-up phenomenon. In order to confirm the analysis result, an experimental circuit was constructed and the input current was checked. If the supply current is sufficient, it is confirmed that over-current flows and starts. If the supply current is insufficient, the circuit cannot start and a latch-up phenomenon occurs.

본 논문에서는 어댑터나 배터리에 의해 단일전원을 공급받는 IT기기에서, 저렴한 buck 소자를 이용해 마이너스 전압을 발생할 때 발생하는 문제점을 분석하였다. 원인 분석을 위해 buck 소자의 동작원리와 inverter 회로의 원리를 살펴보고, buck 소자를 이용해 inverter 회로를 구성했을 떄의 회로적 특성을 분석하였다. 분석 결과 buck 소자를 이용한 inverter회로는 초기에 큰 기동전류가 필요함을 확인하였으며, 특히 전원을 공급하는 회로에서 기동전류에 미치지 못하는 전류용량일 경우 래치 업 현상과 유사한 상태에 빠질 수 있음을 확인하였다. 분석결과를 확인하기위해 실험회로를 구성하고 입력전류를 확인한 결과, 공급전류가 충분한 경우 과전류가 흐르면서 기동됨을 확인하고, 공급전류가 충분치 않은 경우에는 회로가 기동하지 못해 래치 업 현상이 발생해 회로 전체가 위험상태에 도달함을 확인하였다.

Keywords

References

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