Maxim Integrated Products

In some applications, measuring the power (voltage and current) delivered to a load is more important than simply measuring the current with a conventional current-sense amplifier. In particular, loadpower measurement enables accurate power management in applications, such as battery-powered devices, that can be powered by either a battery or by an AC adapter. This application note shows how to create a simple analog multiplier (from the MAX4210D/E/F) that is capable of multiplying two input signals ranging from 0 to 1V, and thus of ensuring accurate load-power measurement.