Medical devices involve the safety of patients' lives, so special attention shall be paid to the accuracy and quality of the device, especially ECGs, defibrillators, and other devices, where medical staff must master the physiological characteristics of patients in critical moments to fulfill the heavy responsibility of saving lives. The article will introduce the requirements of ECG application and the characteristics of ECG analog front-end devices introduced by ADI.
The market demand for multi-physiological parameter monitors is rising rapidly
It is often necessary to use multi-physiological parameter monitors to monitor the physiological characteristics of patients in medical applications, and there are many uses in hospitals, including the operating room (OR), emergency room (ER), cardiac care unit (CCU), intensive care unit (ICU), electrophysiology (EP) laboratory/catheterization laboratory, telemetry/Holter unit, sleep disorder center, surgical step-down unit, general medical floor, and implantable pacer/defibrillator surgical suite, etc.
In addition, the demand for portable devices in=home/out-of-hospital is also increasing, from Holter-type unit and other devices (such devices record multiple ECG channels, including a blood pressure cuff that record blood pressure regularly), to a home version of a polysomnogram device that can record multiple physiological parameters, as well as deep brain stimulators that can effectively reduce or suppressing muscle tremors caused by Parkinson's disease, transcranial magnetic stimulators for treating severe depression, glucometers and insulin pumps for stabilizing blood sugar levels in patients, etc.
ECG analog front-end accelerates product development
ADI saw the market demand and introduced the ADAS1000 ECG analog front end, which can measure ECG signal, thoracic impedance, pacing artifacts and lead-on /lead-off status, and output this information in the form of a data frame, providing lead/vector or electrode data at a programmable data rate. It has the characteristics of low power consumption and being small-sized so it is suitable for battery-powered portable applications. It is also a high-performance device, so it is suitable for high-end diagnostic devices.
ADAS1000-4BSTZ
ADAS1000 has a variety of product combinations. ADAS1000 is a 5-channel ECG with full-featured, integrating respiration and pace detection functions; While ADAS1000-1 only provides an ECG channel without respiration and a pace detection function. In addition, ADAS1000-2 can only be used as a subset of the main device, which provides ECG channel, but has no functions such as respiration, pace, and right leg drive.
The ADAS1000/ADAS1000-1/ADAS1000-2 is designed to simplify the task of acquiring and ensuring high-quality ECG signals. These devices provide a low-power, small-signal data acquisition system for biopotential applications. It also has some auxiliary features which are helpful to improve the quality of ECG signal acquisition, including multi-channel averaged driven lead, selectable reference drive, fast overload recovery, flexible respiration circuit which directly outputs magnitude and phase information, three-leads pacing detection algorithm, and AC or DC lead-off detection options. Multiple digital output options ensure flexibility in monitoring and analyzing signals. In addition, some additional functions such as high sampling output can be performed on external DSP, microprocessor, or FPGA, which can meet the needs of high-end customers. As ECG systems are widely used, ADAS1000/ADAS1000-1/ADAS1000-2 adopts a power consumption/noise scaling architecture to reduce noise at the cost of increased power consumption and can close some unused signal acquisition channels or reduce the data rate to achieve the purpose of saving power.
ADAS1000/ADAS1000-1/ADAS1000-2 provides many features in order to simplify manufacturing test and development and provide the overall power-up test. For example, the calibration DAC provides DC and AC test excitation, cyclic redundancy check (CRC) redundancy test, and read-back function for all relevant register address spaces. The input structure is differential amplifier input, allowing users to choose different configuration options to achieve the best application.
The ADAS1000/ADAS1000-1/ADAS1000-2 is available in two package options, including 56-lead LFCSP and 64-lead LQFP. They operate at a rated temperature range of −40℃ to +85℃ and can be used in ECG monitoring and diagnosis, bedside patient monitoring, portable telemetry, Holter, automated external defibrillator (AED), cardiac defibrillator and ambulatory monitor, pacemaker programmer, patient transport and stress testing.
ADAS1000 can support biopotential signal input and digital signal output has five ECG acquisition channels and one driven lead and can be connected in parallel with multiple ICs for measuring 10 or more electrodes. The master device ADAS1000 or ADAS1000-1 can be used together with the slave device ADAS1000-2, which can support AC and DC lead-off detection, and has internal three leads pacing signal detection algorithms. It can support user's digital pacing signal, measure thoracic impedance (internal/external path), selectable reference lead, provide scalable noise and power control and power-down mode, and the device has low power consumption capability of 11 mW(1 lead), 15 mW(3 leads) and 21 mW (all electrodes).
In addition, ADAS1000 also provides lead or electrode data and supports medical standards such as AAMI EC11:1991/(R)2001/(R)2007 and AAMI EC38, including R2007, EC13:2002/(R)2007, IEC60601-1 ed. 3.0 b:2005, IEC60601-2-25 ed. 2.0:2011, IEC60601-2-27 ed. 2.0 b:2005, IEC60601-2-51 ed. 1.0 b: Version 2005, etc., supports fast overload recovery, low-speed or high-speed data output rate, and provides SPI/QSPI™/DSP compatible serial interface. The size of the 56-lead LFCSP package is 9 mm × 9 mm, and the main body size of the 64-lead LQFP package is 10 mm × 10 mm. The ADAS1000 ECG analog front end also won the 2011 Best Electronic Design Award in the Medical category.
EVAL-ADAS1000SDZ
ADI also introduced the EVAL-ADAS1000SDZ to speed up product development, which is a full-featured evaluation kit for ADAS1000. The evaluation kit includes an evaluation board with two ADAS1000 devices, which can display ECG capture up to 12 leads. The kit contains a medical-grade +5V wall adapter, equipped with a global interchangeable wall plug, and the attached CD contains user software for data capture and display. All ADAS1000 registers can be controlled by the software, capture and display ECG data, respiration data, pace pulse detection, and store data for offline processing.
The EVAL-ADAS1000SDZ evaluation board is only used for silicon chip evaluation, and cannot be directly connected to animals or human bodies. The evaluation board can be used together with the system development platform (SDP) or can be directly interfaced with SDP through a dedicated serial interface connector (J4). The SDP controller board is connected to a PC through USB 2.0, evaluation board is connected to the SDP controller board, DAS1000 evaluation board cannot be directly connected to a PC, and evaluation software running on PC communicates with the evaluation board through the SDP controller board.
Conclusion
The modern clinical practice relies heavily on multi-physiological parameter monitors to pay attention to patients' physiological characteristics. Medical devices need to constantly improve their technology to monitor the immediate condition, change, and change rate, and it also needs to improve its accuracy and quality, reduce its size, and make progress in data capture, transmission, and storage technology. ADAS1000 can help meet the above needs and is the best choice for related medical device manufacturers.
RELATED PRODUCT