Digital Heart Beat Sensor

Overview

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 micro controller 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.

Digital Heart Beat Sensor:

Features

•  Heart beat indication by led 
• Compact size. 
• Total heart beat count can be obtained serially every minute.

 

Applications

• Digital heart rate monitor. 
• Bio-feedback control of robotics and applications exercise machines.

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. 

 

ATMEL SCHEMATIC:

ATMEL CODE:

For a sample code please Click Here

Finger Print Sensor

Overview

The U.are.U 4500 Reader is a USB fingerprint reader featuring an elegant, sleek design with a soft, cool blue glow and, of course, the unsurpassed performance DigitalPersona is known for. Made for power-users and shared environments, the 4500 is the natural choice for those who want and need the very best.

Finger Print Sensor:

Features:

• Blue LED: Soft, cool blue glow fits into any environment. Provides a pleasing presence; doesn't compete in low light environments, such as restaurants, or conflict with alarm condition colors, such as in healthcare.

• Small form factor: Conserves valuable desk space.

• Rugged construction:High-quality metal casing weighted to resist unintentional movement. 

• Special undercoating: Stays where you put it because of a special undercoating.  

• Excellent image quality: High-quality optics ensure best image every time.

 
For Codes and design please CLICK HERE