See Every Watt, Save Every Microamp: PAC1711 and PAC1811 Power Monitors

See Every Watt, Save Every Microamp: Microchip Cuts Power in Half for Digital Power Monitors

Measuring power and current across a sense resistor inevitably consumes some power itself—a necessary trade-off in electronic design. Most electronics designers agree that, given the same cost and bill of materials, minimizing the power lost during measurement is highly desirable. Reducing this measurement overhead not only improves overall system efficiency but also helps meet stringent energy requirements in modern applications.

Microchip’s leadership in digital power monitoring was established with our win of EDN’s Hot 100 Products in 2018 with the 4 channel, 16-bit precision PAC1934 and will grow these new releases of the PAC1711 and PAC1811 for lower power consumption.

The PAC1711/1811 establish new lows for power consumption expectations that will be of interest to the systems designers of IoT, portable electronics, mobile computing, automotive, communication and industrial products.

In this post, you’ll discover the key advantages and unique features of our new PAC1711 and PAC1811 digital power monitors—offering 12-bit and 16-bit low power measurement, respectively. Specifically, you will learn about:

• Significantly Reduced Power Consumption: The PAC1711 and PAC1811 consume up to 50% less typical power compared to previous 12-bit and 16-bit digital power monitors.
• Advanced Accumulation Registers: These registers enable accurate tracking of system power usage over time and facilitate system characterization.
• Flexible Alert Configuration: Individual limit registers for under/over current, under/over voltage and overpower conditions enhance system protection and monitoring.
• Step Limit Alert Feature: A new alert mechanism that highlights deviations from running averages in power-related registers, helping to quickly identify abnormal power events.
• Pin-Compatible Design: Both devices are available in SOT23 eight-lead packages, making them easy drop-in replacements for existing systems.

By the end of this post, you’ll understand how these features can help you optimize power measurement and management in your designs.

The Evolving Challenge of Power Monitoring

The need for more efficient power monitoring continues to grow, driven by several industry trends. Longer-lasting battery-powered applications deliver greater value to the end customers of smart home electronics, mobile computing, IoT devices and portable electronics. Additionally, the rising cost of electricity in homes and buildings makes energy efficiency a top priority related to the cost of ownership. The increasing power demands of graphics chips for AI and data centers further highlight the importance of active power monitoring to optimize system configurations and maximize energy savings.

As a result, a flexible set of tools for understanding power consumption is crucial for managing battery life and system reliability. For example, a warehouse robot must accurately estimate the energy required to return to its charging station, while a laptop used for graphic design may need to monitor increased power from its graphics processor. Unfortunately, most single-channel digital power monitors measuring 48V and below do not offer accumulation registers, a useful and relatively new feature for tracking energy usage over time.

Moreover, designers are constantly searching for better mechanisms to identify power milestones for control and system housekeeping. Definable notifications that trigger actions when limits are approached or exceeded help maintain system reliability. These warnings facilitate warranties, remote system checks and allow telematics potentially saving companies the cost of a service call. Where alerting is concerned, it is again notable that for single-channel digital power monitors for less than or equal to 48V, few suppliers have multiple alert registers to designate different values for different power related everts. This feature makes the PACs more valuable to the user.

Finally, in light of supply chain challenges brought on by the COVID-19 pandemic, planning for second-source components has become increasingly important. Finding packages readily available and footprint compatible under power monitors would make it easier for designers to source multiple devices and provide production continuity.

Key Advantages of PAC1711 and PAC1811

1. Significantly Lower Power Consumption—No Compromise on Performance
   
   PAC1711 and PAC1811 deliver more efficient measurement while maintaining a high sampling rate of 1024 samples per second (default) and up to 16ksps. Unlike some products that increase sampling rates at the expense of effective number of bits (ENOB), these devices maintain full 12-bit and 16-bit resolution, respectively, without sacrificing accuracy or performance. Most importantly, power consumption is half that of similar devices.
   
   
2. Advanced Measurement Tools for Battery and Power-Critical Applications
   
   Both devices feature an accumulation register and accumulation alert to track total power consumed. This capability is instrumental for understanding battery life in fully charged systems, analyzing battery consumption across different usage models and monitoring changes in system performance over time.
   
   
3. Flexible and Granular Power-Related Alerts
   
   The PAC1711 and PAC1811 offer up to two alert pins and specific alert limits for VBUS overvoltage or undervoltage, VSENSE overcurrent or undercurrent, fast rising or falling voltage or current, overpower warnings, overpower critical events and accumulator fullness. These individually assignable alerts provide designers with precise control and early warning for a wide range of power-related events.
   
   
4. Early Detection of Power Variability
   
   With the new step alert limit, these devices can track large changes to a running average, providing early warning for significant or worsening changes in power consumption. Configurations allow for defining a rising or falling event specifying how large the variation can be from the last reading. This feature helps designers quickly identify and address abnormal power events.
   
   
5. Supplier Flexibility and Confidence
   
   Adoption of the VDFN-8, SOT23-8 footprint compatible package allows the PAC1711 and PAC1811 to serve as drop-in replacements for other digital power monitors. This compatibility provides peace of mind for procurement teams and large manufacturers, supporting supply chain resilience and design flexibility. And for customers of low power monitors, we offer a VDFN-10 which separates Sense+ and Vbus to allow low-side power configuration.

Conclusion: Power Monitoring Enhanced for Efficiency

With the PAC1711 and PAC1811, we deliver a new standard in digital power monitoring—combining ultra-low power consumption, advanced measurement features and robust system protection in a familiar, easy-to-integrate package. Whether you’re designing for battery-powered IoT, high-performance computing or industrial automation, these devices empower you to see every watt and save every microamp.

Ready to Optimize Your Next Design?

Contact your Microchip representative or visit our website to learn more about the PAC1711 and PAC1811 and request samples.