RF modules speed time to market for medical device designers

Microsemi's ZL70123 base station module, when combined with the company's existing ZL70323 implant module, provides a complete solution for achieving the highest performance in next-gen medical networks (Med-Net). Both modules are based on the latest generation of Microsemi's ultralow power (ULP), MICS-band, radio transceiver chip, which has been deployed in more than three million implantable devices over the last ten years.

Radio frequency technology is increasingly being used in a wide variety of medical implantable applications, including cardiac care, physiological monitoring (e.g. insulin monitoring), pain management and obesity treatments.

According to a recent report from P&S Research, the market for active implantable devices, which includes pacemakers, defibrillators and neurostimulators, is expected to grow at an eight percent compound annual growth rate (CAGR) over the next five years, reaching nearly $29bn by 2023. Microsemi's new ZL70123 base station module is suited for the unique needs of this growing market.

"RF engineering is a highly specialised discipline, and leveraging Microsemi's deep expertise in this area allows our customers to reduce design times and minimise project risk," said Martin McHugh, Microsemi's Product Line Manager for implant modules. "With Microsemi's two-module radio link, companies can now focus research dollars and development efforts on new therapies that enable a better quality of life."

Microsemi's Med-Net radio operates in the 402-405MHz MICS band. Multiple ULP wake-up options are supported, including a 2.45GHz, industrial, scientific and medical (ISM) band, wake-up option.

The existing Microsemi ZL70323 implant module implements all RF-related functions needed to deploy an implant node in a MICS-band RF telemetry system. It consumes less than 6mA when transmitting or receiving data and consumes 10nA when in its sleep state. The integrated antenna tuning circuit allows the module to be used with a wide range of implant antennas (as nominal antenna impedance is 100+j150Ω). The module includes the following major blocks: 

• ZL70103-based MICS-band RF transceiver with integrated matching network, SAW filters for suppression of unwanted blockers and antenna tuning; 
• 2.45GHz wake-up receiver matching network;
• Integrated 24MHz reference frequency crystal; and 
• Decoupling capacitors.

The new Microsemi ZL70123 base station module includes all RF-related functions required to deploy external device functions in a MICS-band RF telemetry system. It is designed to meet regulatory requirements including Federal Communications Commission (FCC), European Telecommunications Standards Institute (ETSI) and International Electrotechnical Commission (IEC) standards. Additional features include:

• Integrated matching network with a nominal 50Ω RF port;
• Bandpass filter for suppression of unwanted blockers;
• 2.45GHz wake-up transmitter with a nominal 50Ω RF port; and
• Fully shielded, 18×12×3mm package.

"The ZL70123 base station module raises the bar in implant telemetry by offering more flexibility, longer range capability and smaller size than its predecessor while maintaining backward compatibility with older systems," said Jeff Kuhn, Application Manager for Microsemi. "Combining the ZL70123 base station module with the ZL70323 implant module, Microsemi's Med-Net radio solution enables deeper implants with strong communication links while preserving battery power."