Power budget
also: energy budget · current budget · battery life estimate
An accounting of how much power each part of a product draws in each operating mode, used to size batteries and supplies and to predict battery life.
A power budget lists each subsystem (processor, radio, sensors, display, actuators, regulators) with its current in each state (active, transmitting, idle, asleep) and how long it spends in each over a typical day or duty cycle. Multiplying and summing gives average current or power; dividing usable battery capacity by that average estimates runtime. For mains-powered products it sizes the power supply and the thermal design.
The estimate is only as good as its usage assumptions: how often the user interacts, how often the radio reconnects, how long the display stays on. Measuring real prototypes with a current profiler over representative use routinely surprises teams.
Where it bites: batteries deliver less than rated capacity in the cold, at high currents and as they age, and regulators have losses, so budgets need margin.
Founder takeaway
Build the power budget alongside the architecture, measure real current profiles on early prototypes, and design with margin for cold, aging and real user behavior.
engineer review pending