Plastic Remote Control With 45keys Black Case For TCL/ SKYWORTH/ CHANGHONG Tv
The luminous efficiency of infrared light-emitting diodes can only be accurately determined by special instruments, but can only be roughly determined by the pull-apart method in amateur conditions.The infrared receiving tube of the receiving part is a photosensitive diode.
In the practical application to the infrared receiving diode add reverse bias, it can work normally, that is, the infrared receiving diode in the circuit application is the reverse application, so as to obtain higher sensitivity.
Infrared receiving diodes are generally round and square.
Since the transmitting power of infrared led is generally small (about 15mW), the signal received by infrared receiving diode is relatively weak, so it is necessary to increase the high-gain amplifier circuit.
Some years ago, some special amplifiers such as PC1373H and CX20106A were commonly used.In recent years, whether amateur production or formal products, most of the finished infrared receiver
There are basically two kinds of packaging for the finished infrared receiver: one uses iron shield;One is plastic packaging.There are three pins, namely, positive power supply (VDD), negative power supply (GND) and data output (VO or OUT).The arrangement of the pins of the infrared receiving head varies with different models, please refer to the manufacturer's instructions.The advantage of the finished infrared receiver is that it does not need complex debugging and shell shielding, so it is very convenient to use like a triode.But pay attention to the carrier frequency of the infrared receiver when using.
The carrier frequency commonly used for infrared remote control is 38kHz, which is determined by the 455kHz ceramic vibration used at the transmitter.
At the transmitting end, integer frequency division of crystal oscillator is required. The frequency division coefficient is generally 12, so 455kHz÷12≈ 37.9khz ≈38kHz.There are also some remote control systems with 36kHz, 40kHz, 56kHz, etc., which are generally determined by the oscillation frequency of the transmitter crystal oscillator.
The characteristics of infrared remote control is not to affect the surrounding environment, not to interfere with other electrical equipment.Because it is impenetrable to walls, household appliances in different rooms can be used with a universal remote control without interfering with each other.Circuit debugging is simple, as long as the given circuit connection is correct, generally do not need any debugging can be put into work;Easy to encode and decode, can be multi - channel remote control.
As a result of each manufacturer produced a large number of infrared remote control special integrated circuits, when the need to follow the picture can be.Therefore, infrared remote control in household appliances, indoor short distance (less than 10 meters) remote control has been widely used