Four Tips for Making Better Power Rail Measurements
应用文章
Power distribution networks, or PDNs, have become a key technology focus in electronic design. Because PDNs are routed to all devices that need power, any noise or transients on power rails propagate throughout the system. Hence, noise and coupling on power rails is often the number one source of system jitter. Power integrity measurements such as measuring ripple, noise, and finding sources of transient and period disturbances have become much tougher to accurately measure. Why is this? Oscilloscope offset is often not adequate when zoomed at small vertical sensitivities. The lower power rails have tighter tolerances that are often buried by oscilloscope and probe noise. Connecting with a probe or coax cable can change the behavior of the power rail or can mask signal detail.