原标题：TI AFE4900可穿戴无线多参数病人监护器参考设计TIDA-01580

　　TI公司的AFE4900是超低功耗集成模拟前端(AFE),用于同步化心电图(ECG)和光电血管容积图(PPG)信号收集,也可用于光生物检测应用如心率监测(HRM)和外周血氧饱和度(SpO2).同步PPG和ECG信号采集数据速率高达1kHz,PPG接收器动态范围高达100 dB.本文介绍了AFE4900主要特性和框图,以及采用AFE4900的可穿戴无线多参数病人监护器参考设计TIDA-01580主要特性,框图,电路图,材料清单和PCB设计图.

　　The AFE4900 device is an analog front-end (AFE) forsynchronized electrocardiogram (ECG),photoplethysmogram (PPG) signal acquisition. Thedevice can also be used for optical bio-sensingapplications, such as heart-rate monitoring (HRM)and saturation of peripheral capillary oxygen (SpO2).

　　The PPG signal chain supports up to four switchinglight-emitting diodes (LEDs) and up to threephotodiodes (PDs). The LEDs can be switched onusing a fully integrated LED driver. The current fromthe photodiode is converted into voltage by thetransimpedance amplifier (TIA) and digitized using ananalog-to-digital converter (ADC). The ECG signal chain has an instrumentation amplifier (INA) with aprogrammable gain that interfaces to the same ADC.

　　A right-leg drive (RLD) amplifier set can be used tothe bias for the ECG input pins. AC and dc lead-offdetect schemes are supported. The ADC codes fromthe PPG and ECG phases can be stored in a 128-sample first in, first out (FIFO) block and read outusing either an I2C or a serial programming interface(SPI) interface.

　　AFE4900主要特性:

　　• Synchronized PPG, ECG Signal Acquisition atData Rates Up to 1 kHz

　　• ECG Signal Chain:

　　– Standalone ECG Acquisition Up to 4 kHz

　　– Input Bias: 1-Lead ECG With RLD Bias

　　– Programmable INA Gain: 2 to 12

　　– Input Noise (1 Hz to 150 Hz): 2.5 μVrms at1 kHz, 1.25 μVrms at 4-kHz Data Rate

　　– AC, DC Lead-Off Detect: 12.5-nA to 100-nA

　　• PPG Receiver:

　　– Supports Three Time-Multiplexed PD Inputs

　　– 24-Bit Representation of Current From PD

　　– DC Offset Subtraction DAC (Up to ±126-μA) atTIA Input for Each LED, Ambient

　　– Digital Ambient Subtraction at ADC Output

　　– Noise Filtering With Programmable Bandwidth

　　– Transimpedance Gain: 10 kΩto 2 MΩ

　　– Dynamic Range Up to 100 dB

　　– Receiver Operates in PPG-Only mode atApproximately 1-μA/Hz Sampling Rate

　　– Power-Down Mode: Approximately 0 μA

　　• PPG Transmitter:

　　– Four LEDs in Common Anode Configuration

　　– 8-Bit LED Current Up to 200 mA

　　– Mode to Fire Two LEDs in Parallel

　　– Programmable LED On-Time

　　– Simultaneous Support of Three LEDs forSpO2, or Multiwavelength HRM

　　– Average Current of 30 μA Adequate for aTypical Heart-Rate Monitoring Scenario:

　　– 20-mA Setting, 60-μs Pulse Duration,25-Hz Sampling Rate

　　• Clocking Using an External or Internal Clock

　　• FIFO With 128-Sample Depth for ECG and PPG

　　• I2C, SPI™ Interfaces: Selectable by Pin

　　• Operating Temperature Range: –20℃ to +70℃

　　• 2.6-mm × 2.1-mm, 0.4-mm Pitch DSBGA Package

　　• Supplies:

　　– Rx: 1.8 V to 1.9 V (LDO Bypass),

　　2.0 V to 3.6 V (LDO Enabled)

　　– Tx: 3 V to 5.25 V

　　– IO: 1.7 V to Rx_SUP

　　AFE4900应用:

　　• Synchronized PPG, ECG for Blood PressureEstimation

　　• HRM for Wearables, Hearables

　　• Heart-Rate Variability (HRV)

　　• Pulse Oximetry (SpO2) Measurements

　　可穿戴无线多参数病人监护器参考设计TIDA-01580

　　TIDA-01580 Wearable, Wireless, Multi-Parameter Patient Monitor Reference Design This reference design is a simple, wearable, multiparameter,patient monitor that uses a single-chip,biosensing front end, the AFE4900 device, forsynchronized electrocardiography (ECG) andphotoplethysmography (PPG) measurements. Themeasured data is transferred to a remote locationusing the CC2640R2F device (supporting BLE 4.2 and5). The reference design is operated using a singleCR3032 battery and provides a battery life of 30 days.

　　The raw data is available for the user to calculateheart rate, oxygen concentration in blood (SpO2),pulse-transit time (PTT), and ECG. Two onboard lightemittingdiodes (LEDs) indicate low-battery detectionand ECG lead-off detection for users.

　　病人监护器参考设计TIDA-01580主要特性:

　　• Simple, Wearable, Multi-Parameter, Patient Monitorfor PPG and ECG

　　• Provides Raw Data to Calculate Heart Rate, SpO2,and PTT

　　• Uses Single-Chip, Biosensing Front-End AFE4900Device for Synchronized ECG and PPGMeasurements

　　– PPG (Optical Heart-Rate Monitoring and SpO2)Supports Four LEDs and Three Photodiodes(PDs), With Digital Ambient Subtraction toImprove Signal-to-Noise Ratio (SNR)

　　– ECG (LEAD I) Signals

　　• Integrated Arm® Cortex®-M3 and 2.4-GHz RFTransceiver (CC2640R2F) Supports Wireless DataTransfer – BLE 4.2 and 5.0

　　• Operated By CR3032 (3-V, 500-mA Coin-CellBattery), With Battery Life of 30 Days Using HighlyEfficient DC/DC Converters

　　• Small Form Factor Helps With Easy Adaptation toWearable Applications

　　病人监护器参考设计TIDA-01580应用:

　　• Wireless Patient Monitor

　　• ECG

　　• Pulse Oximeter

　　• Wearable Fitness and Activity Monitor

　　图.病人监护器参考设计TIDA-01580外形图

　　图.病人监护器参考设计TIDA-01580 PCB顶视图(无电池夹头)

　　图.病人监护器参考设计TIDA-01580 PCB底视图

　　病人监护器参考设计TIDA-01580材料清单:

　　详情请见:

afe4900.pdf

tidrw34.zip

tidudo6.pdf