Swiss electronics company ST Microelectronics has released a set of antenna-matching companion chips for STM32WL33 wireless microcontrollers (MCUs) to simplify the development of IoT, smart-metering and remote-monitoring applications.

The MLPF-WL-01D3, 02D3 and 04D3 ICs combine impedance matching and harmonic filtering on a single glass substrate to optimise the main radio’s RF performance, leveraging proprietary integrated passive device (IPD) technology.

Precision engineered and housed in a compact package, the integrated devices are said to ensure right-first-time design while saving development time, bill-of-materials costs and board space.

Integrating antenna protection, the devices simplify the RF connection to the MCU. In addition to ensuring optimal performance, integrated matching and filtering also increases reliability and reduces overall cost by eliminating the need to combine multiple discrete components.

There will be seven variants, letting designers optimise for radio operation in high-band (826-958MHz) or low-band (413-479MHz), high-power (16dBm/20dBm) or low-power (10dBm), and for four-layer or two-layer PCB designs. The non-conductive glass substrate ensures performance with low temperature drift, and the chip-scale package measures 1.47 by 1.87mm and is 630µm high after reflow.

The long-range sub-GHz radio of the STM32WL33 wireless MCUs can operate in either of the 413-479MHz and 826-958MHz licence-free bands and with up to 20dBm output power where local regulations permit.

With an Arm Cortex-M0+ core and selected peripherals also on-chip, the integrated wireless MCUs simplify the design of remote-monitoring equipment for smart city, smart agriculture and smart industry. Applications include smart meters, and safety systems, asset-trackers, and proximity detection.

Reference designs (STDES-WL3xxxx, www.st.com/resource/en/data_brief/stdes-wl3c2sll.pdf), pre-certified and fine-tuned for STM32WL33 MCUs, are also available.

The MLPF-WL-0xD3 antenna-matching devices are entering production in a five-bump CSPG chip-scale package, priced from $0.15 for orders of 1000 pieces.

For more information visit www.st.com/rf-filter-for-stm32wl33.