한국전기전자재료학회:학술대회논문집 (Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference)
- 한국전기전자재료학회 2010년도 하계학술대회 논문집
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- Pages.14-14
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- 2010
LED Driver IC를 위한 고전압 전류감지 회로 설계
A High-Voltage Current-Sensing Circuit for LED Driver IC
- Min, Jun-Sik (Dept. of Semiconductor Eng., Chungbuk National University) ;
- No, Bo-Mi (Dept. of Semiconductor Eng., Chungbuk National University) ;
- Kim, Yeo-Jin (Dept. of Semiconductor Eng., Chungbuk National University) ;
- Kim, Yeong-Seuk (Dept. of Semiconductor Eng., Chungbuk National University)
- 발행 : 2010.06.16
초록
A high voltage current sensing circuit for LED driver IC is designed and verfied by Cadence SPECTRE simulations. The current mirror pair, power and sensing MOSFETs with size ratio of K, is used in our on-chip current sensing circuit. Very low drain voltages of the current mirror pair should be matched to give accurate current sensing, so a folded-cascode opamp with a PMOS input pair is used in our design. A high voltage high side LDMOST switch is used between the current sensing circuit and power MOSFET to protect the current sensing circuit from the high output voltage. Simulation results using 0.35um BCD process show that current sensing is accurate with properly frequency compensated opamp.