Finger clip heart rate oxygen saturation scheme

Finger clip heart rate oxygen saturation scheme

1. Scheme overview:

Blood oxygen saturation (SpO2) is the percentage of the capacity of oxygenated hemoglobin (HBO2) carrying oxygen molecules in the blood to the capacity of all hemoglobin (HB), that is, the concentration of blood oxygen in the blood. It is an important physiological parameter of the respiratory and circulatory system.

Blood oxygen is known as the fifth largest physical sign parameter after heart rate, blood pressure, body temperature and respiratory rate. Generally, it is recognized that blood oxygen saturation should not be less than 94% if it is normal, and oxygen supply is insufficient if it is less than 94%. Some scholars and clinical experts set 90% of blood oxygen saturation as the standard of hypoxemia.

Finger clip pulse oximeter has the advantages of small volume, low power consumption, convenient use and portability. When measuring, just insert your finger into the finger clip photoelectric sensor, and the display screen will directly display the measured blood oxygen saturation value and heart rate value.

2. Measurement principle:

The measurement principle of oh0918 finger clip heart rate and blood oxygen saturation scheme of yundian high tech is based on the absorption spectral characteristics of hemoglobin (HB) and oxygenated hemoglobin (HBO2) in the red and near red light region, the empirical formula of data processing is established by using Lambert Beer's law, and the photoelectric blood oxygen detection technology combined with optical capacitance pulse oscillography (PPG) technology is adopted, Two beams of light with different wavelengths: 660nm red light and 905nm near-infrared light irradiate the human finger end through the transmission finger clip sensor, and the measurement signal is obtained by the photosensitive component. After being processed by the front-end signal processing chip and microprocessor, the measured result can be displayed on the display screen or other suitable display methods.

3. Technical parameters:

3.1 display mode: 0.96 color screen, adjustable four-way display;

3.2 finished power supply: two 1.5V (AAA) batteries;

Internal working voltage: 2.3V ­- 3.0V；

Working current: ≤ 30mA (including display drive);

3.3 measurement method: photoelectric blood oxygen detection technology combined with photoplethysmography (PPG)

3.4 output mode: 0.96 color screen display or Bluetooth (the default is 0.96 color screen. If Bluetooth is required, the customer shall provide app protocol in advance);

3.5 heart rate (PR)

Measurement range: 25bpm --- 250bpm

Measurement accuracy: ± 2bpm

3.6 blood oxygen saturation (SpO2):

Effective measurement range: 70% - 100%

Measurement accuracy: 90% - 100% ± 1%; 80% - 89% segment ± 2%; 70% - 79% segment ± 3%;

3.7 perfusion index (PI):

Measurement range: 0.5-30;

Measurement performance under weak perfusion: when the pulse filling degree is 6%, it can correctly display the blood oxygen saturation value and heart rate value;

3.8 fast corresponding speed: stable heart rate and blood oxygen values can be obtained within a few seconds;

3.9 automatically exit after 8 seconds without finger insertion;

3.10 typical product dimensions (Reference): 58 x 34 x 38mm (L x W x H), weight: About 45g;

3.11 operating environment

Service temperature: 5 ℃ --- 40 ℃;

Service humidity: ≤ 90% RH;

Atmospheric pressure: 860-1060hpa;

Equipment that cannot be used when there is flammable anesthetic gas mixed with air or flammable anesthetic gas mixed with oxygen or nitrous oxide;

3.12 electrical safety classification: BF type application part

4. Sample description of display content (product prototype):

5. Functional features of the scheme:

◆ self developed algorithm and high-performance MCU;

◆ 0.96 high resolution color screen, adjustable four-way display;

◆ fast corresponding speed: stable heart rate and blood oxygen values can be obtained within a few seconds;

◆ blue and yellow, clear and intuitive;

◆ rich output indicators: blood oxygen saturation, heart rate, perfusion index, pulse wave, etc;

◆ wide effective measurement range of blood oxygen saturation: 70% - 100%;

◆ small size, light weight and easy to carry;

◆ automatically exit after 8 seconds without finger insertion;

6. Business and technical services:

6.1 after signing the "business contract", draw the PCB drawing according to the size provided by the customer, provide Geber documents and product BOM list, and the customer can arrange the production of PCBA by itself. Help customers debug the product prototype.

6.2 after meeting a certain purchase quantity (according to the "business contract" signed by both parties), the customer customization fee shall be refunded.

7. List of key components (oh0918 nesting) and procurement requirements:

model describe encapsulation Minimum package (PCS) Procurement requirements

SF9209 Algorithm MCU LQFP_ forty-eight three thousand Mandatory

HR6706 Signal processing IC TQFN3X3-16L three thousand Mandatory

HR6208 Signal processing IC SOT23-5 three thousand Mandatory

YK1802A/B Blood oxygen sensor

(medical grade)

Free purchase