Bioimpedance AFE reduces power consumption and size for RPM devices

Analog Devices Inc. has launched a new bioimpedance (BioZ) analog front-end (AFE) that reduces the size and extends the battery life of remote-patient monitoring (RPM) devices. The MAX3009 bioimpedance AFE offers clinical-grade vital sign measurements of bioimpedance analysis for patient health assessment in battery-powered wellness wearables and medical-grade patches.

Click for a larger image. (Source: Analog Devices, Inc.)

Analog Devices developed the MAX30009 as a low-power design with a range of options to enable use-case power optimization that reduces the power draw on the batteries. This helps extend the operational life of the BioZ and wearable health-care devices.

The MAX30009 is said to reduce power consumption by 62 percent compared to the closest competitive product and also is 30 percent smaller than the closest competitor, enabling designers to reduce the size of the vital sign measurement devices. The device offers ultra-low-power operation of 250 μW at 1.8-V AVDD and is housed in a small 2.028 × 2.028 mm, 25-bump wafer-level package (WLP). It also offers ultra-low-power lead-on detection during standby mode.

The MAX30009 monitors a range of BioZ modalities through simultaneous I and Q measurements, 2-electrode (bipolar), and 4-electrode (tetrapolar) configurations. This enables inputs for BioZ modality measurements as well as a wide range of sample rates from 16 sps to 4 ksps and a wide frequency range of 16 Hz to 891 KHz, according to the company.

The wider range provides greater insights into patient health by measuring respiration rate, galvanic skin response and electrodermal activity, body composition and fluid analysis, bioimpedance spectroscopy, impedance cardiography, and plethysmography, said Analog Devices.

MAX30009 block diagram. Click for a larger image. (Source: Analog Devices, Inc.)

Available now, the MAX30009 is priced at $5.26 per 1,000 units. An evaluation kit, MAX30009EVKIT#, also is available and is priced at $198.22. The kit consists of two boards: the MAXSENSORBLE_EVKIT_B microcontroller (MCU) board and the MAX30009_EVKIT_B sensor board containing the MAX30009. It’s powered by a lithium-polymer battery that is charged via a USB-C cable.

Also targeting RPM applications is Analog Devices’ MAX86178 triple-system vital signs AFE, introduced in the third quarter of 2021. This single-chip AFE integrates three measurement systems to obtain four common vital signs: electrocardiogram (ECG or EKG), heart rate (ECG or optical photoplethysmography, or PPG), blood-oxygen saturation (SpO2), and respiration rate (using BioZ).