Battery-operated devices and energy-restricted applications must track and monitor power consumption without wasting power in the process. To solve this challenge, Microchip Technology announced two digital power monitors that consume half the power of comparable solutions based on typical operating conditions at 1024 samples per second. The PAC1711 and PAC1811 power monitors achieve this efficiency milestone while also providing real-time system alerts for out-of-limit power events and a patent-pending step-alert function for identifying variations in long-running averages.
The 42V, 12-bit single-channel PAC1711 and 16-bit PAC1811 monitors are housed in 8- and 10-pin Very Thin Dual Flat, No-Lead (VDFN) packages, respectively, that are pin- and footprint-compatible with the popular Small Outline Transistor (SOT23)-8 package. This compatibility simplifies second-sourcing for developers, while streamlining upgrades and integration into existing systems.
“Until now, portable devices and a variety of energy-constrained applications have needed to burn a significant amount of valuable power to measure how much they are consuming,” said Keith Pazul, vice president of Microchip’s mixed-signal linear business unit. “Unlike many existing solutions, Microchip’s power monitors function as independent ‘watchdog’ peripherals, eliminating the need for the MCU to handle power monitoring tasks. These monitors allow the MCU or host processor to remain dormant until a significant power event occurs such as needing an LCD screen to power on.”
The PAC1711 and PAC1811 power monitors’ step-alert capability keeps a running average of voltage and current values. If there is a significant, user-defined variation, it will notify the MCU to act on it. The devices keep a rolling average, and any new sample can trigger an alert. A slow-sample pin option is available, which can delay the power usage sampling to every eight seconds and further conserve power.
An accumulator register in the power monitor can be used to manage logistical items, track system battery aging or time to recharge, and provide the short-term historical data for long-term power usage that the MCU can be programmed to act on. Both current monitor integrated circuits sense bus voltages from 0 to 42 volts and can communicate over an I2C interface. They are well-suited for first- or second-source options in computing, networking, AI/ML and E-Mobility applications.
