심자도 신호획득을 위한 실시간 256-채널 12-bit 1ks/s 하드웨어 = Real-time 256-channel 12-bit 1ks/s Hardware for MCG Signal Acquisition

다국어 초록 (Multilingual Abstract)

A heart diagnosis system adopts Superconducting QUantum Interface Device(SQUID) sensors for precise MCG(MagnetoCardioGram) signal acquisitions. Such system needs to deal with hundreds of sensors, requiring fast signal sampling and precise analog-to-digital conversions(ADC). Our development of hardware board, processing 64-channel 12-bit in 1 ks/s speed, is built by using 8-channel ADC chips, 8-bit microprocessors, SPI interfaces, and specially designed parallel data transfers between microprocessors to meet the 1ks/s, i.e. 1 mili-second sampling interval. We extend the design into 256-channel hardware and analyze the speed using the measured data from the 64-channel hardware. Since our design exploits full parallel processing, Assembly level coding, and NOP(No OPeration) instruction for timing control, the design provides expandability and lowest system timing margin. Our result concludes that the data collection with 256-channel analog input signals can be done in 201.5㎲ time-interval which is much shorter than the required 1 mili-second period.

참고문헌 (Reference)

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