Silicon Laboratories and IMST have combined hardware and software in the iM871A wireless M-Bus module, designed for the smart energy market. The module offers a cost-effective RF solution for smart metering applications connecting water, heat, electricity and gas meters with data concentrators in the 868MHz frequency band. The wider frequency band is suitable for offices and buildings where multiple electronics can cause interference. The module uses the Si1002 micrcocontroller to achieve a link budget up to 120 dB when operating in R2 mode. The module is compact, with a small footprint of 17x19mm and has a serial interface as well as analogue and digital inputs and outputs to accommodate interfaces with a customer's system. It complies with the EN 13757-4 standard. With a standby current of less than 1µA, the module preserves battery life, making it suitable for use in water and gas meters which require 12 years operation. The module is compatible with other wireless M-Bus devices and supports all major uni-directional and bi-directional wireless M-Bus modes, i.e. S1, S2, T1, T2 and R2, in addition to all tolerance specifications.
