Medical Telemetry

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Medical devices are increasingly incorporating wireless functionality to support new monitoring, diagnostic and therapeutic applications that are improving patient care and lowering healthcare costs.

Delivering high data rates, ultra-low power consumption and unique wake-up circuitry, the ZL70101 system-on-a-chip has been designed into a range of implanted medical devices, including pacemakers, implanted cardioverter defibrillators (ICDs), neurostimulators, drug pumps and physiological monitors, and associated external monitoring and programming equipment.

Operating in the Medical Implant Communications Service (MICS) frequency band, the highly integrated ZL70101 radio chip delivers data rates up to 800 kbps while consuming just 5 milliamps (mA) of power. By using the high data rate with heavy duty cycling, the average power consumed can be very small. To further conserve implanted device battery life, the ZL70101 incorporates a unique "wake-up" receiver that allows the chip to operate in an extremely low current 250 nanoamp (nA) "sleep" mode. Communication is then initiated using a specially coded wake-up signal from the base station transmitter. How low is the power demand of the ZL70101?

If the ZL70101 was powered by a typical AA battery, it would work for over 300 hours in normal operation continually transmitting and receiving data at high speed. Assuming the battery had no self-discharge, the ZL70101 could be powered in sleep mode by an AA battery for over 800 years.
A pacemaker patient undergoes routine follow-up with a physician to assess their health and the operating condition of the implanted device. A pacemaker powered by a typical lithium-iodide battery and equipped with the ZL70101 could transfer 10 Mbytes of data at 500 kbits per second every three months. This would consume only about 1% of the total capacity of the pacemaker battery, corresponding to about a one month reduction in implant battery lifetime when compared to the same type of pacemaker not fitted with the ZL70101.
If the ZL70101 was powered by a typical lithium-iodide pacemaker battery, the chip can transfer 1 Mbyte of data at 500 kbits per second every day for 10 years while only consuming about 10% of the total capacity of the battery.

The ZL70250 ultra low-power RF chip provides a wireless link in applications where power consumption is of primary importance, including battery-powered body area networks relying on energy harvesting, wireless sensors and voice communication. The tranceiver's ultra low-power requirements allow the use of a button cell battery or energy harvesting methods, enabling devices with extremely small form-factor. The IC operates in unlicensed frequency bands between 795-965 MHz and offers data rates up to 186 kbps to support voice communication.