Equation 1 · Part 3 · Edge AI Electronics and Sensor Systems in Practice: An Advanced Technical Guide
Symbol f_i
What this part means
the fraction of time the device spends in power state i (sleep, always-on monitoring, escalated inference, radio).
Its job in the formula
is an input to the expression that computes the quantity on the left.
Full expression→Symbol f_i→Article meaning
Where the article explains it
Here is the fraction of time the device spends in power state i (sleep, always-on monitoring, escalated inference, radio) and is the measured — not datasheet-typical — power draw in that state.
The passage around this formula
…without a bench measurement at each state, is analysis built on unverified vendor numbers stacked several layers deep; a single shunt measurement campaign, even a short one, converts most of that stack into fact. Here is the fraction of time the device spends in power state i (sleep, always-on monitoring, escalated inference, radio) and is the measured — not datasheet-typical — power draw in that state. This formulation is worth writing out because it exposes the one lever that dominates every other…
Learn the underlying idea
A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.
Open the illustrated subscripts: which member of a family? guide →
See this notation across published equations →
Sources cited in the article section
- [8] Hello Edge: Keyword Spotting on Microcontrollers ↗
- [10] Sub-mW Keyword Spotting on an MCU: Analog Binary Feature Extraction and Binary Neural Networks ↗
- [3] MLPerf Tiny Benchmark ↗
These citations provide research context; check each source for the exact claim it supports.