6.4.1 · D3 · HinglishPower, Thermal & Reliability

Worked examplesDynamic vs static power consumption

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6.4.1 · D3 · Hardware › Power, Thermal & Reliability › Dynamic vs static power consumption

Yeh page ek drill hai har us case ke liye jo dynamic/static power formulas mein aa sakta hai. Hum parent page ke do master formulas se shuru karte hain aur koi step assume nahi karte. Agar koi symbol aata hai, toh woh ya toh yahan define kiya gaya hai ya pehle 6.4.1 Dynamic vs static power consumption mein.

Recall Woh formulas jo hum har jagah use karenge

Dynamic power = do switching-related terms ko saath mein add karo: Zyaadatar cases mein short-circuit term chota hota hai, isliye hum aksar use karte hain; Cell E mein explicitly handle kiya gaya hai. Static (leakage) power: Total: .

Meanings (plain words mein):

  • ::: activity factor — clock ticks ka woh fraction jisme ek node actually flip karta hai, 0 aur 1 ke beech
  • ::: load capacitance farads mein — kitna charge ek node ko voltage change karne ke liye move karna padta hai
  • ::: supply voltage volts mein — woh "height" jitni charge pump ki jaati hai
  • ::: clock frequency hertz mein — flips per second
  • ::: leakage current amps mein — "off" transistors se guzarne wali trickle
  • ::: short-circuit (shoot-through) power — woh energy jo tab jalti hai jab dono transistors thodi der ke liye saath conduct karte hain

The scenario matrix

Har power question in case classes mein se ek (ya unka blend) hota hai. Neeche, har class ko kam se kam ek fully worked example milta hai, jise uske cell letter se tag kiya gaya hai.

Cell Case class Kya toot-ta hai / kya dekhna hai
A Plain plug-in (saare values diye hain, non-zero) unit prefixes pico/giga/milli cleanly cancel hone chahiye
B Dynamic power ka voltage scaling (ratio question) dominance — kabhi linear scale mat karo
C Frequency scaling mein linear — lekin real DVFS, ko se tie karta hai
D Activity factor extremes ( aur ) ⇒ dynamic vanish, sirf leakage bachti hai
E Short-circuit term aur cutoff term zero ho jaati hai, negative nahi
F Static vs dynamic crossover (idle chip) low activity par kaun sa term jeetega?
G Real-world word problem (battery / TDP) watts → joules → hours translate karo; dono terms scale hote hain
H Static power ki linear voltage scaling , nahi
I Exam twist (combined scaling + solve-for-unknown) ek saath do variables change karo, ya formula invert karo

Neeche wali figure is poore page ka map hai: nau coloured tiles, ek har case class A–I ke liye. Jab tum har example work karo, apna letter tile par dhundho — tile colours worded steps mein reuse hote hain (lavender = voltage lever, coral = ratio/scaling lever, mint = frequency ya word-problem, butter = activity ya leakage) taaki ek nazar mein pata chale ki woh case kaun sa lever pull kar raha hai. Neeche ki caption formula notice karo: har tile bas ke ek piece par stress daalne ka tarika hai.

Figure — Dynamic vs static power consumption

Cell A — Plain plug-in


Cell B — Voltage scaling of dynamic power


Cell C — Frequency scaling


Cell D — Activity factor extremes


Cell E — Short-circuit term aur uska cutoff


Cell F — Static vs dynamic crossover


Cell G — Real-world word problem


Cell H — Static power ki linear voltage scaling


Cell I — Exam twist


Recall Self-check

Agar activity factor 0 hai, toh kya total power zero hai? ::: Nahi — dynamic power zero hai lekin static (leakage) power rehti hai. 20% voltage cut se switching power kitna kam hoti hai? ::: Lagbhag 36% (factor ). 30% voltage cut se static power kitna kam hoti hai? ::: Exactly 30% — static mein linear hai. Short-circuit power exactly zero kab hoti hai? ::: Jab ; formula ko 0 par clamp karo, kabhi negative nahi.

Yeh bhi dekho: CMOS Inverter Design · Thermal Design Power (TDP) · FinFET Transistors · Subthreshold Slope · Signal Transition Time · Amdahl's Law