Seeed Studio's LoRa-E5 Is an All-in-One, Ultra-Compact, Sub-$10 Microcontroller and LoRa Module
12x12mm stamp-format module includes an Arm Cortex-M4 and Semtech's SX126X radio in one low-cost part.
Seeed Studio has launched a low-cost, ultra-compact LoRa module with embedded Arm Cortex-M4 microcontroller and costing under $10 — and it's giving away five of the modules anyone designing prototypes through its Seeed Fusion PCBA service.
"LoRa-E5 is a low-cost, ultra-low power, extremely compact, and high-performance LoRaWAN module designed by Seeed," the company writes of its latest product, brought to our attention by CNX Software. "It contains ST system-level package chip STM32WLE5JE, and STM32WLE5 is the first SoC integrated with the combo of LoRa RF and MCU chip. This module is also embedded with ARM Cortex-M4 ultra-low-power MCU and LoRa SX126X and therefore supports (G)FSK mode and LoRa."
Measuring just 12x12mm (around 0.47x0.47in), the compact stamp-format surface-mount module is powered by STMicroelectronics' STM32WL system-on-chip, which incorporates an Arm Cortex-M4 microcontroller running at 48MHz and a Semtech SX126X radio.
The radio half of the package supports (G)FSK and LoRa operation, including LoRaWAN, with 6.25kHz, 125kHz, 250kHz, and 500kHz bandwidth modes for LoRa operation; the microcontroller has 64kB static RAM (SRAM) and 256kB of flash memory, along with three UARTs, one I2C, one SPIO, and one 12-bit analog-to-digital converter (ADC) pin.
Two models of the module have been confirmed: The HF variant offers 868/915MHz operation, while the LF — yet to appear on the Seeed Studio website — is for use in countries which require 434/470MHz operation. According to Seeed, both parts are rated for operating temperatures between -40 and 85°C (around -40 to 185°F) and offer a 2.1uA wake-on-radio sleep mode.
To encourage use of both the module and its PCB assembly service, Seeed has a launch offer: Anyone designing a board around the LoRa-E5 module can receive five pieces free of charge, providing the prototypes are manufactured through its Seeed Fusion PCBA service. For those looking to just pick up the bare modules, they're now available at $9.90 each.