KAGA FEI Packs Bluetooth 6.0 Into an 8.55mm Module

KAGA FEI has expanded its Bluetooth Low Energy module line with the ES4L15MA1, covered by CNX Software on August 20, 2026. The module measures 8.55 by 3.25 by 1.00 mm, roughly the footprint of a grain of rice, and the interesting part is not the size. It is that the module ships with embedded firmware exposing a command-based API over UART, so a product can gain Bluetooth 6.0 without anyone writing a line of wireless stack code.

• The ES4L15MA1 measures 8.55 x 3.25 x 1.00 mm and integrates a PCB antenna covering 2402 to 2480 MHz at +8dBm
• It is built on Nordic's nRF54L15, an Arm Cortex-M33 at 128MHz with a RISC-V coprocessor, 256KB SRAM, and 1.5MB of non-volatile storage
• Bundled firmware provides a UART command API with Peripheral and Central roles and multi-connection to up to 8 devices
• Sampling is scheduled for January 2027 with mass production from February 2027

What Is Inside the ES4L15MA1?

The silicon is Nordic's nRF54L15, which pairs an Arm Cortex-M33 application core running at 128MHz with a RISC-V coprocessor for peripheral handling. On-module memory is 256KB of SRAM and 1.5MB of non-volatile storage. The radio does Bluetooth 6.0 at up to 2Mbps and supports the angle-of-arrival and angle-of-departure direction finding features, which is what enables indoor positioning rather than simple proximity detection.

Supply is 1.7V to 3.6V with dedicated low-power modes, so a single coin cell or a small lithium cell is a realistic power source. We looked at the same SoC in a bare prototyping form when Nordic's nRF54L15 Tag arrived for coin-cell IoT work, and the tradeoffs across this class of part are laid out in our low-power wireless MCU guide.

Why Does the Embedded Firmware Matter More Than the Size?

KAGA FEI already shipped an ultra-small module on this SoC, the ES4L15BA1, back in 2024, and the two share the same tiny form factor. What the ES4L15MA1 adds is software. According to KAGA FEI's announcement, the module comes with ready-to-use embedded firmware providing a command-based API over UART, supporting Peripheral and Central roles, multi-connection to as many as 8 devices, an SPP-like Bluetooth LE profile, configurable custom GATT services, and firmware update over the air or over UART. Power Save and Deep Sleep modes are exposed through the same interface.

That changes who can use it. A team building a medical device or an industrial sensor can treat Bluetooth as a serial peripheral driven by simple commands from their existing microcontroller, skipping the stack integration work that typically dominates the schedule. It is the difference between shipping a component and shipping a subsystem.

What Does It Cost and When Can You Get One?

Sampling begins in January 2027 with mass production from February 2027, so this is a design-in announcement rather than something to order this week. KAGA FEI has not published pricing for the ES4L15MA1; the closely related ES4L15BA1 has been quoted under $10 in volume, which is a reasonable anchor but not a confirmed figure for the new part.

On compliance, the module is certified for FCC in the United States, MIC in Japan, and ISED in Canada, is RoHS compliant, and is designed to meet PSA Certified Level 3 for IoT security. Pre-certification is the other half of the time saving here, because radio certification is the schedule risk that catches first-time hardware teams.

For more embedded and wireless hardware coverage, follow our mini computer section.

Sources: CNX Software — August 20, 2026; RF Globalnet — August 2026, carrying KAGA FEI's own announcement.