Low Power Estimator — InnovChip

Low Power Estimator

Estimate average current, power draw and battery life for a battery-powered STM32 design by mixing run / sleep / stop modes and duty cycles.

Calculator

About This Calculator

For battery devices the average current — not the peak — decides battery life. The estimator blends the current of each low-power mode with the fraction of time spent in it, then converts to power and back-calculates runtime from battery capacity.

How to Use

  1. Measure or source the datasheet sleep/stop currents for your part at your VDD.
  2. Enter realistic dwell times (percentages); the leftover percentage is assumed to be spent in stop/standby.
  3. Enter the battery capacity of your cell (e.g. 200 mAh coin cell or 1000 mAh LiPo).
  4. The estimator reports average current, power, and battery life in hours and days.

Formulas

Average currentI(avg) = I(run)·%run + I(sleep)·%sleep + I(stop)·%stop
Average powerP(avg) = I(avg) × V(bat)
Battery lifeLife = Capacity / I(avg)

Design Notes

Standby current from the datasheet is often quoted at a specific VDD — scale your estimate if the real supply differs.

Include always-on peripherals (RTC, backup registers, LDO quiescence) in the stop/standby current figure.