Sponsored by Nordic Semiconductor
Bluetooth® Low Energy (LE) is the backbone of modern low-power wireless products, from smart home sensors and medical monitors to asset trackers and industrial nodes. Yet, despite its efficiency at the radio level, the performance — and the user experience — is still often bottlenecked by poor power management at the system level.
Most Bluetooth LE devices are powered by primary cells like AA, AAA, or coin cells, chosen for their long shelf life and compact form factor. However, managing energy from these sources isn’t trivial.
Designers face three persistent challenges when working with primary cell batteries:
- How to boost voltage efficiently from a slowly dying battery.
- How to accurately gauge remaining energy, especially near end-of-life.
- How to minimize leakage current during storage, transport, and idle periods.
- Shipping a product with the battery already inserted.
Without addressing these power challenges, even the most optimized Bluetooth stack and device implementation can result in unpredictable battery life, device failure in the field, and unsatisfactory user experiences. Not to mention that these issues are even magnified in high-volume deployments, where battery replacement costs and downtime multiply quickly.
This is where Nordic Semiconductor’s new nPM2100 PMIC enters the equation. Designed specifically for low-power wireless applications, the nPM2100 addresses the systemic energy loss that most Bluetooth LE designs tolerate by default.
With 95% boost efficiency at typical BLE current draws, sub-200nA idle modes, and industry-leading fuel gauge precision, it represents a fundamental shift in how engineers can approach power in primary-cell BLE designs.
In this blog post, we will explore:
- How does the nPM2100 work?
- What makes it different from traditional solutions?
- How can it be leveraged to extend battery life, reduce system complexity, and design more sustainable Bluetooth LE products?
- How can you evaluate the nPM2100?
- A video demo of Nordic’s nPM PowerUP tool paired with the nPM2100 Evaluation Kit.
Meet the nPM2100
nPM2100 is Nordic Semiconductor’s first power management IC (PMIC) engineered specifically for primary cell-powered Bluetooth LE applications. While traditional PMICs often cater to general-purpose power needs, the nPM2100 is optimized from the ground up for low-power wireless systems with strict energy and space constraints.
One of its standout features is a built-in model-based fuel gauge that delivers accurate battery capacity estimates — without the need for external components. This allows Bluetooth devices to report remaining energy down to 5% precision towards the end of battery life for AA and LiMnO2 batteries, helping prevent unexpected shutdowns and reducing premature battery replacements, which is especially valuable in remote or high-volume deployments.
Additional feature highlights include:
- Exceptional efficiency at ultra-low currents — with over 90% efficiency down to 10 µA and up to 95% at 70 mA
- Ultra-low power modes, drawing just 35 nA in ship mode and 175 nA in hibernate mode
- A compact footprint, available in 1.9 × 1.9 mm WLCSP or 4 × 4 mm QFN packages
- A minimal BOM, requiring only six passive components, makes it ideal for space-constrained designs like wearables and smart tags
This combination of high-efficiency regulation, accurate fuel gauging, and compact integration makes the nPM2100 a powerful enabler for longer-lasting, smarter Bluetooth LE devices.
Deep Dive: What Makes the nPM2100 Different
LDO and Boost Converters
Bluetooth LE devices must operate within a narrow voltage range, even as battery voltage drops. Regulators ensure this stability, and the nPM2100 employs both boost converters and a Load Switch (pass-through mode) to manage power effectively.
- LDOs, or Low Dropout Regulators, lower a higher input voltage to a lower output voltage. They’re simple and quiet in terms of electrical noise but inefficient when the input voltage greatly exceeds the output. This inefficiency is especially apparent in primary cell designs where energy conservation is crucial.
- In contrast, boost converters increase a lower input voltage to a higher, stable output. This is particularly valuable when working with depleted batteries that still hold usable energy. The nPM2100’s boost converter is optimized to deliver high efficiency, both during active radio bursts and in ultra-low power sleep states.
When the battery voltage is already adequate to run the system, the nPM2100 switches to pass-through mode. This allows the battery to supply power directly to the system through a low-resistance path, avoiding unnecessary energy conversion losses. The chip can dynamically switch between boost and pass-through modes, ensuring optimal efficiency throughout the battery’s life.
At the heart of the nPM2100 is a highly efficient boost converter that supports operation from input voltages as low as 0.9 V. It provides up to 95% efficiency at higher loads (70 mA) and maintains over 90% efficiency at currents as low as 10 µA. This ensures stable voltage output across the battery’s discharge curve, which is essential for Bluetooth LE operation.
System Reliability
The nPM2100 provides several safety and recovery features that increase system robustness. If a device fails to boot — perhaps due to memory corruption or voltage instability — the PMIC can automatically trigger a power cycle to restore operation. This is especially valuable for remote or hard-to-service installations.
Additionally, the integrated watchdog timer ensures the system can recover from software hangs, while a hardware reset line offers a manual fallback for developers or end users.
The device also supports one-button system control, enabling a single GPIO to act as an on/off toggle with the same ultra-low current draw as ship mode.
Seamless Integration
With a BOM consisting of just six passives, the nPM2100 integrates cleanly into any Bluetooth LE architecture, especially when paired with Nordic’s nRF52, nRF53, or nRF54 series SoCs via I²C. This minimal design footprint is ideal for products where space and battery life are both at a premium.
Power Saving
The nPM2100’s ultra-low power modes (hibernate mode at 175 nA current draw) enable remarkable energy savings when paired with Bluetooth LE SoCs in advertising-only use cases.
Devices configured with a 2.5-minute advertising interval can achieve up to 25% longer battery life, while a 4-minute interval can yield a 50% improvement. At 9-minute intervals or longer, battery life can extend by up to 2 to 3 times. These improvements can significantly reduce maintenance frequency in battery-operated systems like BLE beacons and environmental sensors.
The device also supports zero-drain deployment. With a ship mode consuming only 35 nA, manufacturers can insert batteries at the factory without compromising shelf life. Devices can then wake via a button press or TWI command. The 175 nA hibernate mode enables scheduled wake-ups based on timers ranging from 16 ms to over 74 hours, offering significant flexibility for periodic sensing applications.
The Fuel Gauge
Accurate fuel gauging is another critical feature. The nPM2100 employs a model-based algorithm that provides precise estimates of battery life, especially near end-of-life conditions, achieving 5% accuracy. This level of detail is crucial for devices in regulated sectors or with strict replacement schedules, such as healthcare or industrial monitoring.
Use Cases: From Bluetooth Beacons to Health Monitors
Smart home sensors that report infrequently benefit immensely from the nPM2100’s hibernate mode, which reduces sleep current to sub-microamp levels. This can extend battery life to multiple years on a single coin cell.
Asset trackers, often assembled and shipped in bulk, benefit from the ability to insert batteries at the factory using ship mode. The device can remain dormant during transit and activate only when deployed, saving energy and logistics complexity.
Bluetooth LE-based remotes and peripherals gain reliability from an integrated watchdog and reset functionality, preventing lockups and ensuring consistent performance with minimal user intervention. Meanwhile, medical and industrial wearables benefit from precise battery monitoring, allowing scheduled maintenance and improved user trust.
Real-World Example
Consider a Bluetooth LE-enabled temperature and humidity sensor used in smart buildings. It sends data every 5 minutes and is expected to last at least 18 months on a CR2032 battery.
- Without the nPM2100, such a design might consume 2.5 µA in sleep and struggle with boost converter inefficiencies. Fuel gauging might also be unreliable, leading to premature battery replacements.
- With the nPM2100, sleep and hibernate current drops to between 0.5 and 1.0 µA. Boost efficiency is improved, battery reporting is accurate to within 5%, and the device can ship with a battery pre-installed.
The result is a 2.5× increase in battery life, more reliable battery alerts, and lower BOM complexity, all of which lead to a more robust and scalable product.
Environmental Impact
By dramatically extending battery life, the nPM2100 supports more sustainable product lifecycles. In large-scale deployments, this translates into meaningful environmental and cost savings.
For example, deploying 10,000 sensors with a 2-year battery lifespan requires 30,000 replacements over a 10-year span. Extending battery life to 5 years reduces that number to just 10,000 — a 66% reduction in e-waste and service overhead.
Combined with its low-leakage modes and support for pre-assembly battery installation, the nPM2100 enables greener, more efficient designs that scale better both technically and economically.
nPM2100 EK and the nPM PowerUP Application
Nordic provides multiple tools to ease the adoption of the nPM2100:
The nPM2100 EK
The nPM2100 Evaluation Kit is the simplest way to evaluate the nPM2100 solution. It interfaces seamlessly with Nordic development boards, offering rapid prototyping without a complex setup.
The nPM PowerUP App
Part of the nRF Connect for Desktop suite of apps, it enables designers to simulate and optimize boost efficiency, fuel gauge settings, and wake-up configurations.
Developers can select from pre-configured battery profiles or create their own in the nPM PowerUP App, tuning thresholds and gauging behavior to match their application. With I²C control via the nRF Connect SDK, developers can program wake timers, adjust power settings, and configure system events directly from firmware.
🎥 Video: Unboxing and Demo
Now, it’s time to demo the nPM2100 EK using the nPM PowerUP application available within the nRF Connect for Desktop suite of apps!
Closing Thoughts
The nPM2100 isn’t just a more efficient boost converter — it’s a comprehensive energy management platform tailored to the unique needs of BLE products. Its combination of fuel gauging, intelligent regulation, supervisory controls, and ultra-low power modes makes it a compelling choice for any engineer designing small, battery-powered wireless systems.
Whether you’re building a wearable, a beacon, or an industrial sensor node, the nPM2100 allows you to reduce BOM complexity, extend battery life, and deliver a better product experience.
