ADI公司的ADAS1000/ADAS1000-1/ADAS1000-2是低功耗心电图(ECG)模拟前端，实现了12导联心电图(ECG)信号测量,呼吸测量,起搏信号检测和导联脱落检测等功能.支持AAMI EC11:1991/(R)2001/(R)2007,AAMI EC38 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: 2005.主要用在ECG监测器和诊断,病人监视器,Holter,手持遥测设备等.本文介绍了ADAS1000主要特性,功能框图,以及12导联ECG测量系统设计方案框图,电路图和PCB元件布局图等.

The ADAS1000/ADAS1000-1/ADAS1000-2 measure electro cardiac (ECG) signals, thoracic impedance, pacing artifacts, and lead-on/lead-off status and output this information in the form of a data frame supplying either lead/vector or electrode data at programmable data rates. Its low power and small size make it suitable for portable, battery-powered applications. The high performance also makes it suitable for higher end diagnostic machines.

The ADAS1000 is a full-featured, 5-channel ECG including respiration and pace detection, while the ADAS1000-1 offers only ECG channels with no respiration or pace features. Similarly, the ADAS1000-2 is a subset of the main device and is configured for gang purposes with only the ECG channels enabled (no respiration, pace, or right leg drive).

The ADAS1000/ADAS1000-1/ADAS1000-2 are designed to simplify the task of acquiring and ensuring quality ECG signals. They provide a low power, small data acquisition system for biopotential applications. Auxiliary features that aid in better quality ECG signal acquisition include multichannel averaged driven lead, selectable reference drive, fast overload recovery, flexible respiration circuitry returning magnitude and phase information, internal pace detection algorithm operating on three leads, and the option of ac or dc lead-off detection. Several digital output options ensure flexibility when monitoring and analyzing signals. Value-added cardiac post processing is executed externally on a DSP, microprocessor, or FPGA.

Because ECG systems span different applications, the ADAS1000/ADAS1000-1/ADAS1000-2 feature a power/noise scaling architecture where the noise can be reduced at the expense of increasing power consumption. Signal acquisition channels can be shut down to save power. Data rates can be reduced to save power.

To ease manufacturing tests and development as well as offer holistic power-up testing, the ADAS1000/ADAS1000-1/ ADAS1000-2 offer a suite of features, such as dc and ac test excitation via the calibration DAC and cyclic redundancy check (CRC) redundancy testing, in addition to readback of all relevant register address space.

The input structure is a differential amplifier input, thereby allowing users a variety of configuration options to best suit their application.

The ADAS1000/ADAS1000-1/ADAS1000-2 are available in two package options, a 56-lead LFCSP package and a 64-lead LQFP package. Both packages are specified over a ?40℃ to +85℃ temperature range.

ADAS1000主要特性:

Biopotential signals in; digitized signals out
5 acquisition (ECG) channels and one driven lead
Parallel ICs for up to 10+ electrode measurements
Master ADAS1000 or ADAS1000-1 used with slave ADAS1000-2
AC and dc lead-off detection
Internal pace detection algorithm on 3 leads
Support for user’s own pace
Thoracic impedance measurement (internal/external path)
Selectable reference lead
Scalable noise vs. power control, power-down modes
Low power operation from
11 mW (1 lead), 15 mW (3 leads), 21 mW (all electrodes)
Lead or electrode data available
Supports AAMI EC11:1991/(R)2001/(R)2007, AAMI EC38 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: 2005
Fast overload recovery
Low or high speed data output rates
Serial interface SPI-/QSPI?-/DSP-compatible
56-lead LFCSP package (9 mm × 9 mm)
64-lead LQFP package (10 mm × 10 mm body size)

ADAS1000应用:

ECG: monitor and diagnostic Bedside patient monitoring, portable telemetry, Holter, AED, cardiac defibrillators, ambulatory monitors, pace maker programmer, patient transport, stress testing


图1.ADAS1000系列功能框图

12导联ECG测量系统设计方案

心电图(ECG)系统通过测量活组织表面电位来记录心脏在一段时间内的电性活动。它使用生物电位电极来拾取身体特定部位的心脏信号，两个电极间的差分电压或某一电极与多电极平均电压之间的差分电压可在测量后显示为ECG输出上的一个通道。

本参考设计采用ADI公司最新推出的ADAS1000系列低功耗心电图(ECG)模拟前端，实现了12导联心电图(ECG)信号测量、呼吸测量、起搏信号检测、导联脱落检测等功能。

ADAS1000系列针对生物电信号应用提供了一种低功耗、小型数据采集系统，旨在简化采集和确保高质量ECG信号的任务。ADAS1000系列包括ADAS1000、ADAS1000-1、ADAS1000-2、ADAS1000-3、ADAS1000-4共5个型号。通过单颗芯片或多颗芯片组合，能够测量心电图(ECG)信号、胸阻抗、起搏伪像、导联连接/脱落状态，并将此信息以数据帧的形式输出，以可编程数据速率提供导联/矢量或电极数据。它具有低功耗和小尺寸特性，适合电池供电的便携式应用。它还是一款高性能器件，因此适用于高端诊断设备。

本参考设计中使用的主要芯片有:

ADAS1000（低功耗、5电极ECG模拟前端，提供呼吸测量和脉搏检测）
ADAS1000-2（低功耗、5电极ECG模拟前端配套芯片）
ADuCM361（集成ARM CORTEX M3和单通道Σ-Δ型ADC的低功耗精密模拟微控制器）
ADuM4070（集成反馈功能的隔离式开关稳压器）
ADuM4160（全速/低速USB数字隔离器）
ADuM2401（四通道数字隔离器）
ADuM2281（5 KV RMS双通道数字隔离器）
ADP1612（650 kHz/1.3 MHz升压PWM DC-DC开关转换器，限流值为1.4 A）
ADP7102（20 V、300 mA低噪声CMOS LDO）
ADP151（超低噪声、200 mA CMOS线性调节器）

图2.12导联ECG测量系统框图

图3.12导联ECG测量系统外形图

图4. 12导联ECG测量系统电路图(1)

图5. 12导联ECG测量系统电路图(2)

图6. 12导联ECG测量系统电路图(3)

图7. 12导联ECG测量系统电路图(4)

图8. 12导联ECG测量系统电路图(5)

图9. 12导联ECG测量系统电路图(6)

图10. 12导联ECG测量系统电路图(7)

图11. 12导联ECG测量系统PCB元件布局图

图12. 12导联ECG测量系统PCB设计图
详情请见:
http://www.analog.com/media/en/technical-documentation/data-sheets/ADAS1000_1000-1_1000-2.pdf
ADAS1000_1000-1_1000-2.pdf