Non-Invasive Blood Pressure
The AD8233 is an integrated signal conditioning block for electrocardiogram (ECG) and other biopotential measurement applications. It is designed to extract, amplify, and filter small biopotential signals in the presence of noisy conditions, such as those created by motion or remote electrode placement. This design allows an ultralow power analog-to-digital converter (ADC) or an embedded microcontroller to easily acquire the output signal.
The AD8233 implements a two-pole, high-pass filter for eliminating motion artifacts and the electrode half cell potential.This filter is tightly coupled with the instrumentation amplifier architecture to allow both large gain and high-pass filtering in a single stage, thereby saving space and cost.
An uncommitted operational amplifier enables the AD8233 to create a three-pole, low-pass filter to remove additional noise. The user can select the frequency cutoff of all filters to suit different types of applications.
To improve the common-mode rejection of the line frequencies in the system and other undesired interferences, the AD8233 includes a right leg drive (RLD) amplifier for driven electrode applications. The AD8233 includes a fast restore function that reduces the duration of the otherwise long settling tails of the high-pass filters. After an abrupt signal change that rails the amplifier (such as a leads off condition), the AD8233 automatically adjusts to a higher filter cutoff. This feature allows the AD8233 to recover quickly, and therefore, to take valid measurements soon after connecting the electrodes to the subject.
The AD8233 is available in a 2 mm × 1.7 mm, 20-ball WLCSP package and a 150 μm thin die for height constrained applications. Performance is specified from 0°C to 70°C and is operational from −40°C to +85°C.
- Fitness and activity heart rate monitors
- Portable ECG
- Wearable and remote health monitors
- Gaming peripherals
- Biopotential signal acquisition, such as EMG or EEG
The ADPD105/ADPD106/ADPD107 are highly efficient, photometric front ends, each with an integrated 14-bit analog-to-digital converter (ADC) and a 20-bit burst accumulator that works with flexible light emitting diode (LED) drivers. The accumulator is designed to stimulate an LED and measure the corresponding optical return signal. The data output and functional configuration occur over a 1.8 V I2C interface on the ADPD105 or SPI on the ADPD106 and ADPD107. The control circuitry includes flexible LED signaling and synchronous detection.
The analog front end (AFE) features best-in-class rejection of signal offset and corruption due to modulated interference commonly caused by ambient light.
Couple the ADPD105/ADPD106/ADPD107 with a low capacitance photodiode of <100 pF for optimal performance. The ADPD105/ADPD106/ADPD107 can be used with any LED. The ADPD105 is available in a 2.46 mm × 1.4 mm WLCSP and a 4 mm × 4 mm LFCSP. The SPI only versions, ADPD106 and ADPD107, are available in a 2.46 mm × 1.4 mm WLCSP.
- Wearable health and fitness monitors
- Clinical measurements, for example, SpO2
- Industrial monitoring
- Background light measurements
The ADPD144RI is a highly integrated, photometric front end optimized for photoplethysmography (PPG) detection of blood oxygenation (SpO2) by synchronous detection in red and infrared wavelengths. Synchronous measurement allows rejection of both dc and ac ambient light interference with extremely low power consumption.
The module combines highly efficient, light emitting diode (LED) emitters and a sensitive 4-channel, deep diffusion photodiode (PD1 to PD4) with a custom application specific integrated circuit (ASIC) in a compact package that provides optical isolation between the integrated LED emitters and the detection photodiodes to improve through tissue, signal-tonoise ratio (SNR).
The ASIC consists of a 4-channel analog front end (AFE) with two independently configurable datapaths with separate gain and filter settings, a 14-bit analog-to-digital converter (ADC) with a burst accumulator, two flexible, independently configurable, LED drivers, and a digital control block. The digital control block provides AFE and LED timing, signal processing, and communication. Data output and functional configuration occur over a 1.8 V I2C interface.
- Optical heart rate monitoring
- Reflective SpO2 measurement
The ADPD175GGI is a complete photometric system designed to measure optical signals from ambient light and from synchronous reflected LED pulses. Synchronous measurement offers best-in-class rejection of ambient light interference, both dc and ac. The module integrates a highly efficient photometric front end, three LEDs, and a photodiode (PD). All these items are housed in a custom package that prevents light from moving directly from the LED to the photodiode without first entering the subject.
The front end of the application specific integrated circuit (ASIC) consists of a control block, a 14-bit analog-to-digital converter (ADC) with a 20-bit burst accumulator, and three flexible, independently configurable LED drivers. The control circuitry includes flexible LED signaling and synchronous detection. The analog front end (AFE) features best-in-class rejection of signal offset and corruption due to modulated interference commonly caused by ambient light. The data output and functional configuration occur over a 1.8 V I2C interface.
- Optical heart rate monitoring (HRM)
- Reflective SpO2 measurement
The ADXL355 is part of a new family of low noise density, low 0 g offset drift, low power, 3-axis MEMS accelerometers with selectable measurement ranges. The ADXL355 supports the ±2.048 g, ±4.096 g, and ±8.192 g ranges, and offers industry leading noise, offset drift over temperature, and long term stability, enabling precision applications with minimal calibration and with very low power consumption.
The ADXL355 and ADXL354 (analog output. See ADXL354 Product Page) perform high resolution vibration measurement with very low noise to enable the early detection of structural defects via wireless sensor networks. The low power consumption of the new ADXL354 and ADXL355 accelerometers lengthens battery life and allows extended product usage by reducing the time between battery changes. The low noise performance of the ADXL354 and ADXL355 with low power consumption makes it now possible to cost-effectively enable low level vibration measurement applications such as Structural Health Monitoring (SHM). Additionally, the tilt stability of ADXL354 and ADXL355 accelerometers delivers excellent repeatability over temperature and time, which is ideal for orientation and navigation systems in unmanned aerial vehicles using Inertial Measurement Units (IMUs) and inclinometers. By providing repeatable tilt measurement under all conditions, the new accelerometers enable minimal tilt error without extensive calibration in harsh environments.
The ADXL354 and ADXL355 accelerometers offer guaranteed temperature stability with null offset coefficients of 0.15mg/C (max). The stability minimizes resource and expense associated with calibration and testing effort, helping to achieve higher throughput for device OEMs. In addition, the hermetic package helps ensure that the end product conforms to its repeatability and stability specifications long after they leave the factory.
With output of ±2g to ±8g full scale range (FSR), selectable digital filtering from 1 Hz to 1 kHz, and low noise density of 25µ/√Hz at less than 200µA current consumption, ADXL355 MEMS accelerometer offers performance level comparable to much more expensive devices with less power consumption and BOM cost.
- Inertial measurement units (IMUs)/altitude and heading reference systems (AHRS)
- Platform stabilization systems
- Structural health monitoring
- Seismic imaging
- Tilt sensing
- Condition Monitoring
Industrial Automation Technology (IAT)
- Vital Signs Measurements
- Disease Management and Wellness
- Portable Blood Analyzer
- Wearable Health Monitor