Using parts with margin below their ratings for voltage, current, temperature and so on, rather than at the full rating, to improve reliability. Typical guidelines are voltage at no more than 70 to 80% of rating, or junction temperature at no more than 125 °C against a 150 °C maximum.
Japanese name: ディレーティング
Derating appears in 6 practice questions across 4 topics, including Timing analysis and CDC, How to read datasheets, Power semiconductors.
Field: How to read datasheets
Answer: A. To ensure reliability against switching surge voltages and failures caused by cosmic rays
Real circuits add surge voltages from parasitic inductance during switching, and at sustained high voltage, cosmic-ray neutrons can generate charge inside the device and cause sudden failure (single-event burnout), whose probability rises steeply with voltage. Designers therefore choose devices rated about 1.5× the operating voltage—650 V parts for a 400 V bus, for example—with even more margin at high altitude.
Answer: A. 1.05 ns
OCV derating accounts for delay varying with location even within the same chip, and for setup assumes the most pessimistic combination (slow launch side, early capture clock). The arrival time is 1.1 × (1.0 + 1.5) = 2.75 ns and the required time is 3.0 + 0.9 × 1.0 − 0.1 = 3.8 ns, so the slack is 1.05 ns. 1.40 ns is the value without derating, and 1.25 ns applies the factor to the data path only. In hold analysis the factors are applied the other way around.
OCV derating accounts for delay varying with location even within the same chip, and for setup assumes the most pessimistic combination (slow launch side, early capture clock).
For OCV derating in setup analysis, the launch clock path a…Derating is the design practice of using parts with margin relative to their ratings.
Which correctly describes the concept of component "deratin…OCV applies separate derating factors to data and clock paths, for example making data slower and the capture clock faster in setup analysis, to cover the worst combination.
In static timing analysis, what is the technique called tha…In practice, considering that θJA varies with the board and allowing derating margin, design to keep power below the calculated value.
An IC with maximum junction temperature Tj(max) = 125 °C an…As an Amazon Associate I earn from qualifying purchases.
OCV (on-chip variation) Slack STA (static timing analysis) Setup time CRPR (clock reconvergence pessimism removal) Burn-in Threshold voltage Allowable power dissipation 5 V tolerant Absolute maximum ratings