Compact, Low-Power Solutions for Continuous Glucose Monitoring

For device developers, this growth creates a clear engineering challenge: CGM systems must deliver accurate sensing, reliable wireless transmission, long operating life, and a compact wearable form factor. The attached technical materials identify the key building blocks of a CGM device as a glucose sensor, analog front end, BLE SoC, magnetic switch, and battery or power-management architecture. 
 

Inside a CGM System: From Electrochemical Sensing to Mobile Data

A typical CGM system detects glucose concentration through an electrochemical sensing mechanism. The analog front end, or AFE, processes and conditions the small sensor signals, while the BLE SoC transmits glucose data to a smartphone or dedicated receiver. The magnetic switch can support device activation or calibration functions, and the battery system must provide reliable low-power operation throughout the device lifetime.

Avnet’s CGM solution is designed around this system-level requirement. The solution is built around three key devices: the NXP electrochemical AFE NHS2634, the NXP Bluetooth Low Energy MCU MCXW236, and the ST magnetic switch NMH1000. The attached solution slide also describes the design as a CGM solution that tracks glucose in real time and supports low power consumption, a small footprint, reliable communication, cost efficiency, precise sensing, and security. 
 

Key Solution Advantages

1. High-Accuracy Signal Acquisition with an Optimized AFE

At the heart of the CGM system is the AFE, which must capture extremely small electrochemical sensor currents with high precision. 

The NHS2634 is a compact AFE for electrochemical sensors with NFC support, flexible battery configuration, and support for up to four work electrodes, making it suitable for multi-channel wearable sensing designs.

With configurable multi-electrode support, the platform can be extended to additional electrochemical sensing functions, such as ketone-related sensing, depending on the sensor design.
 

2. Small Form Factor for Wearable CGM Devices

Wearable CGM devices must be compact, lightweight, and comfortable for daily use. The attached market material notes that CGM devices are typically small, lightweight, and designed for comfortable wearing, with water-resistant or waterproof features. 

The NHS2634 is available in a WLCSP25 package measuring 1.92 mm × 1.79 mm, making it suitable for compact wearable designs where PCB space is highly constrained. In addition, the attached solution material describes the Avnet CGM hardware as a compact circular design intended to match the actual product form factor. 
 

3. Flexible Battery Architecture and Ultra-Low-Power Operation

Battery life is a critical factor for user experience in CGM devices. 

The Avnet CGM solution supports flexible battery options using the same hardware platform. According to the attached solution material, MCXW236BIUKAR supports 3V operation, while MCXW236AIUKAR supports 1.5V operation, allowing compatibility with either 3V or 1.5V batteries without hardware redesign. The same source also states that support for low-cost 3V batteries can help reduce BOM cost, while 1.5V batteries offer a smaller form factor and improved energy efficiency. 

The system is optimized for ultra-low power consumption and can support up to 21 days of continuous operation using a 25 mAh battery and may offer a shelf life of up to 24 months.  
 

4. NFC Connectivity for Activation, Programming, Pairing, and Data Readout

CGM devices need secure and convenient ways to support activation, pairing, and device interaction. The attached solution slide states that NFC connectivity enables device activation, contactless programming, out-of-band BLE pairing, and sensor data readout. 

The attached technical material also notes that the NHS2634UK integrates NFC NTAG functionality, reducing the need for 2–3 external components. This can help reduce BOM cost and PCB size while simplifying system design.
 

5. Magnetic Activation for Reliable Device Interaction

The NMH1000T magnetic switch can support low-power activation and shelf-mode management in compact wearable designs. NMH1000 offers less than 3% measurement error, 5 ms response time, and compatibility with high-temperature sterilization processes. NMH1000 operates down to 1.2 V supply voltage, which ensures longer shelf life with ultra-low power consumption (75 nA typ. @ 1 Hz sample rate).

(Source: NMH1000T1 Ultra-Low Power Magnetic Switch Overview | NXP Semiconductors)

For CGM production and use cases that require reliable activation and sterilization compatibility, this magnetic sensing function can support a more robust device design.
 

6. Reduced BOM and Simplified Design

Highly integrated CGM designs can reduce external component count, simplify PCB design, and improve manufacturing reliability. The attached technical material states that the Avnet CGM solution uses a highly integrated architecture that minimizes the number of external components, resulting in a simpler design, lower BOM cost, and improved manufacturing reliability. 

The integration of NFC NTAG functionality in the NHS2634UK also helps eliminate 2–3 external components, further supporting compact and cost-efficient CGM design. 
 

Avnet Solution Overview

Avnet’s CGM solution brings together sensing, signal conditioning, wireless connectivity, activation, and power optimization into a compact wearable-oriented platform. The attached materials position the solution around three major component categories: a hosted analog front-end (AFE) NHS2634 from NXP, a BLE MCU MCXW236 and a magnetic switch from ST.

The solution is designed to support real-time glucose tracking, low power consumption, a small footprint, reliable communication, cost efficiency, precise sensing, and security. Its compact circular board design, flexible 1.5V or 3V battery compatibility, reduced BOM count, and low-power architecture make it well suited for wearable CGM applications where user comfort, operating life, and system integration are key design priorities. 
 

Applications

This solution is designed for Continuous Glucose Monitoring applications with NFC connectivity, temperature measurement, and battery-status monitoring. It can support compact wearable CGM devices that require electrochemical sensing, BLE wireless communication, NFC-based interaction, and reliable magnetic activation within a small low-power system architecture. 
 

Conclusion

As CGM adoption accelerates, device developers need solutions that can balance accuracy, size, power consumption, connectivity, and system cost. Avnet’s CGM solution addresses these requirements through an integrated architecture that combines a high-precision AFE, ultra-low-power BLE connectivity, NFC functionality, magnetic activation, flexible battery support, and compact board design. 

By helping engineers simplify design, reduce component count, and optimize power consumption, Avnet enables the development of next-generation CGM devices that can support real-time glucose tracking and more convenient diabetes management.