This reference design describes an ETSI Cat. 2 receiver-capable RF subsystem for smart meters, fully compliant with the most popular wM-Bus S, T and C-modes at 868 MHz as per EN13757-4:2014. The SimpleLink RF transceiver device delivers market leading blocking, selectivity and RX sensitivity numbers in wM-Bus applications, such as bi-directional flow meters, e-meters and heat cost allocators. This cost-optimized design handles the worst case frequency offset of +-60ppm in S2-mode by utilizing an inexpensive XTAL component. Neither an external SAW filter nor costly TCXO component are needed to meet the specification of the wM-Bus modes @ 868 MHz. Additionally, this design uses a ultra-low Iq DC/DC converter with dynamically adjustable output voltage, enables a new level of optimization of the design's power consumption, significantly extending the battery lifetime.
- Market leading blocking, selectivity and RX sensitivity subsystem for wM-Bus at 868MHz
- Fully compliant with the wM-Bus requirements for S2, T2-Meter and C2-Meter modes
- DC/DC converter with adjustable Vout and 360nA Iq current
- No costly SAW filter and TCXO required
- Two pin-compatible IPC options for Balun + Matching available
- This circuit design is tested and includes test firmware, SRF7 Studio GUI configuration files and getting started guide