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1 1 P a g e A n I S O C e r t i f i e d C o m p a n y Digital Heart Beat Sensor This heart beat sensor is designed to give digital output of heart beat when a finger is placed on it. When the heartbeat detector is working, the top-most LED flashes with each heart beat. This digital output can be connected to microcontroller directly to measure the Beats Per Minute (BPM) rate. It works on the principle of light modulation by blood flow through finger at each pulse. Module dual output mode, digital output is simple, serial output with exact readings. Features Heart beat indication by led. Compact size. Total heart beat count can be obtained serially(ttl) every minute. Instant output digital signal for directly connecting to microcontroller. Module dual output mode, digital output is simple, serial output with exact readings. Applications Digital heart rate monitor. Bio-feedback control of robotics and applications exercise machines. Specifications Parameter Operating Voltage Operating current Heart beat detect Value +5v dc regulated 100mA Indicated by high active pulse

2 2 P a g e A n I S O C e r t i f i e d C o m p a n y Pin Details Pin Name Details 1 out Active high output 2 +5v Power supply 3 gnd Power supply gnd 4 rx receiver 5 tx transmitter Using The Sensor Connect regulated DC power supply of 5 Volts. Black wire is Ground, Next middle wire is Brown which is output and Red wire is positive supply. Place the finger on the marked position, and you can view the beat LED blinking on each heart beat. The output is active high for each beat and can be given directly to microcontroller for interfacing applications. Working The sensor consists of a super bright red LED and light detector. The LED needs to be super bright as the maximum light must pass spread in finger and detected by detector. Now, when the heart pumps a pulse of blood through the blood vessels, the finger becomes slightly more opaque and so less light reached the detector. With each heart pulse the detector signal varies. This variation is converted to electrical pulse. This signal is amplified and triggered through an amplifier which outputs +5V logic level signal. The output signal is also indicated by a LED which blinks on each heart beat.

3 3 P a g e A n I S O C e r t i f i e d C o m p a n y Sample Application: In this application heart beats are displayed on LCD using sensor.

4 4 P a g e A n I S O C e r t i f i e d C o m p a n y /* * Project name: Heartbeat sensor * Copyright (c) Researchdesignlab.com * Description: */ * Test configuration: MCU: AT89S52 Dev.Board: 8051 Oscillator: Software: #include<reg51.h> MHz Keil uvision3 #define LCD_PORT P2 // LCD D0-D7 PINS connected P2 sbit rs=p3^5; sbit en=p3^7; sbit D7=P2^7; sbit rw=p3^6; void busy(); //LCD busy void CMD_WRT(unsigned char); void DATA_WRT(unsigned char); void LCD_WRT(unsigned char *); void unsigned char SCI_ReceiveByte( void ); void main() unsigned char CMD[]=0x38,0x01,0x0f,0x06,0x80,TEMP1,i, REC; for(i=0;i<5;i++) TEMP1=CMD[i]; //write the commands to the LCD CMD_WRT(TEMP1); TMOD=0X20; TH1=0XFD; SCON=0X50; TR1=1; CMD_WRT(0x01); CMD_WRT(0X80); LCD_WRT("Heart Beat"); while(1) REC=0; CMD_WRT(0XC0); while(rec!=0x0a) //9600 BAURD RATE

5 5 P a g e A n I S O C e r t i f i e d C o m p a n y rs=0; //cmd mode REC=SCI_ReceiveByte(); DATA_WRT(REC); rw=0; en=1; en=0; //write void DATA_WRT(unsigned char ch) void DELAY() unsigned int X=800000,y=800000; while(x--); while(y--); void busy() busy(); LCD_PORT = ch; //write cmd to P2 rs=1; rw=0; en=1; en=0; //write D7=1; rs=0; rw=1; while(d7!=0) en=0; en=1; void CMD_WRT(unsigned char val) busy();lcd_port=val; void LCD_WRT(unsigned char *string) while(*string) DATA_WRT(*string++); unsigned char SCI_ReceiveByte( void ) // RECIVING SERIAL DATA unsigned char byte; while(ri!=1); byte = SBUF; RI=0; return byte; // RETURN THE DATA

6 6 P a g e A n I S O C e r t i f i e d C o m p a n y Board Dimensions 51.44mm 30.48mm To buy this product click the below link