This document describes the features and characteristics of the LT2940 power monitor, which can measure the power of a supply or load. It has a high-side current sense range of 4V to 80V, supports full 4-quadrant operation, has a bandwidth of 500kHz, and is suitable for 48V telecom power and intermediate bus voltages in the 5V to 24V range.
The Linear Technology LT2940 is an analog multiplier designed to continuously monitor instantaneous power by simultaneously measuring voltage and current. It simplifies design in power control loops where traditional multipliers lack the necessary operating range or sensitivity, and digital solutions cannot respond rapidly enough.
Key features include a wide 4V to 80V high-side current sense range, full 4-quadrant operation for bidirectional power flow, and a bandwidth of 50kHz. The device provides current-mode outputs (PMON and IMON) suitable for servo loops and includes an integrated comparator with selectable latching for direct control applications.
The device operates with a supply voltage ranging from 4V to 8V.
The current sense inputs can measure up to +200mV differentially.
The PMON output reaches a full scale of +200uA when the input product is 0.4V².