Aiming at problem of complex circuit

low sensitivity and stability of blood-leak detection sensor in artificial liver and blood purification equipment because of using analog circuit design

propose a non-contact digital blood-leak detection circuit design scheme. The sensor uses a single green LED as light source

and light irradiate on TCS230 color sensor through pipe containing liquid

TCS230 receives light intensity information and converts to frequency signal and transmit to MCU STM32

which will judge whether the fluid path occurs bloodleak according to the changes of the frequency values

and communicate with upper PC by RS—485 serial port.Experimental result show that circuit of the sensor is simple

the sensitivity is 100 × 10

-6

it has fast response speed

high reli

ability and strong anti-interference ability

and meet the requirements of clinical testing standards.