현장에서 시험 도중 이더넷이 간혹 끊기는 현상이 있어서 스코프 연결 후 시험했습니다.
비드로 분리한 3.3VDD를 측정하였는데 결과는 20us동안의 3.72V정도 임펄스가 인가되었습니다.
MAXIMUM RATING에는 컨티뉴어스와 순간 임펄스에 대한 내용이 없어서 확인하고자하는데요.
3.6V의 MAXIMUM을 넘어서 3.72V의 순간 전압이 인가가 되었을 경우 CHIP에 영향이 있을까요?
아니면 게런티만 보장 못하는 수준일까요?
The datasheet is clear: “Stressing the device beyond the “Absolute Maximum Ratings” may cause permanent damage”. And absolute maximum rating for power is 3.6V. It does not state about level being continuous or intermittent, therefore you would assume specifying any of these. And in general there’s at least one more variable: the slope (velocity) of the power level change. Internally chip works at 125 MHz, which is 8 ns, and 20 us is 2500 clock cycles. The first affected candidate is PLL losing its lock → making chip’s operation malfunction, from loss of data (your probable case) to latch-up.
As soon as you identified the issue, would be good to fix or at least mitigate it. Show the power circuit, including other power consumers on the lines.
