A 2.5 kV isolation 35 kV/us CMR 250 Mbps digital isolator in standard CMOS with a small transformer driving technique

Shunichi Kaeriyama, Shinichi Uchida, Masayuki Furumiya, Mitsuji Okada, Tadashi Maeda, Masayuki Mizuno

Research output: Contribution to journalArticle

37 Citations (Scopus)


A small-size on-chip transformer-based digital isolator for power control systems is proposed. With a proposed pulse generation and detection scheme that enables a 5 V standard CMOS transistor to utilize GHz-band signals, transformer area is reduced to 1/4-1/8 that of conventional transformers. A test chip achieves a 2.5 kV isolation voltage, a 35 kV/us CMR, a 1.6 mA static current and a 250 Mbps data rate, all which are equal to or superior to those of optocouplers or conventional digital isolators. The developed technology greatly reduces the number of chips in power control systems by allowing integration of multiple isolators in a CMOS chip together with microcontrollers or gate drivers. Moreover, the high-speed low-power capability expands the application potential to include isolated serial links, controller area network (CAN), FlexRay, medical devices, displays, sensors, etc.

Original languageEnglish
Article number6075274
Pages (from-to)435-443
Number of pages9
JournalIEEE Journal of Solid-State Circuits
Issue number2
Publication statusPublished - 2012 Feb 1



  • Coupler
  • gate driver
  • inverter
  • ipm
  • isolator
  • motor drive
  • transformer

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

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