BALF-SPI2-03D3

Overview

The BALF-SPI2-03D3 is an ultra-miniature balun designed for sub-GHz wireless applications. It integrates a matching network and harmonics filter, with impedance customized for STMicroelectronics S2-LP transceivers. The device utilizes IPD technology on a nonconductive glass substrate to optimize RF performance. Key specifications include operation in the 860MHz to 930MHz frequency range, a 50 Ω nominal input impedance, and conjugate matched balun output. It features deep Tx rejection harmonic filtering and low insertion loss. The component is housed in a Chip Scale Package with a 0.4mm pitch, offering a small footprint and low profile of ≤ 630 μm after reflow.

Feature Summary

• Integrates matching network and harmonics filter within an ultra-miniature form factor
• Optimized for high RF performance using IPD technology on a nonconductive glass substrate
• Provides deep Tx rejection harmonic filtering and low insertion loss
• Customized impedance matching specifically for ST S2-LP sub-GHz wireless microcontrollers

Applications

• Sub-GHz wireless communication systems utilizing S2-LP transceivers
• IoT devices requiring compact RF front-end solutions
• Applications demanding reduced RF BOM and PCB area

Procurement Notes

Verify the specific ordering suffix and package variant when sourcing, as STMicroelectronics may offer related baluns with different impedance targets or frequency ranges. Confirm that the selected component matches the intended transceiver model, such as the S2-LP series, rather than other variants like those for STM32WL. Ensure compliance with ECOPACK2 standards if environmental regulations apply to the final assembly. Cross-reference datasheets for precise pinout and thermal requirements during integration.

Selection Notes

Select this component when designing for S2-LP based sub-GHz transceivers operating between 860MHz and 930MHz. It is suitable for designs prioritizing minimal PCB area and simplified impedance matching without external components. Consider its compatibility with 2-layer PCBs and the requirement for conjugate matching to the specific transceiver pins. Evaluate the trade-off between the integrated filter benefits and the fixed impedance characteristics against custom discrete solutions.

Part Context

This balun belongs to STMicroelectronics' family of integrated RF components aimed at simplifying sub-GHz wireless designs. It complements the S2-LP transceiver series by providing pre-tuned RF front-end functionality. The product line emphasizes size reduction and performance optimization through proprietary IPD technology, targeting consumer electronics and IoT markets where space constraints are critical.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Related models such as BALF-SPI2-02D3 exist but target different frequency bands (433-470 MHz) and transceivers. Direct substitution requires verifying impedance matching and frequency range compatibility with the host circuit design.