NEA Design Brief Research

1. Infrared Receiver

1.1. An Infrared Receiver receives the modulated Infrared waves and changes its output.

1.1.1. It is available in many frequency ranges like TSOP1738. The last two digits represents the frequency of the modulated IR rays on which the TSOP responds

1.1.2. The Most common type is TSOP1738 - which reacts when it receives IR radiation modulated at 38Khz.

1.1.3. It has 3 pins. - Ground, Vs(Voltage supplied) and Output pin

2. Infrared Transmitter

2.1. As I am going to use an TSOP1738, we need to generate the modulated IR of 38Khz.

2.1.1. For this, I am going to use a 555 timer in a monostable state.

3. Monostable Circuits.

3.1. A circuit programmed in monostable means that once the circuit is switched on, it will time once and then stop.

3.1.1. In order to start it again, it must be switched on manually a second time.

3.2. A monostable circuit produces a single output pulse when triggered. It is called a monostable because in just one state - "Output low". The "Output high" state is only a temporary one.

3.3. When the switch is pressed PIN 2 goes low

3.4. PIN 3 on a 555 timer goes high switching on the output.

3.5. The current then can flow from the +9v to the 0v turning on the output.

3.5.1. After a period of time the output goes low and stays low. The LED is off.

4. Infrared LEDs

4.1. Infrared LEDs emits infrared light means it emits light in the range of infrared frequency.

4.2. We can not see infrared light through our eyes, as it is invisible to the human eyes.

5. Infrared Transmitters and Receivers are used to control any device wirelessly, means remotely.