Ir led and 38KHZ carrier frequencyThe carrier frequency of ir led is 38kHZ.the 38khz is familiar to us.Why ir led had only taken 38kHZ?
the principle is : carrier frequency at 30khz to 60khz.but the 38khz for almost applications. This is due to translate with 455kHz crystal . the 455kHz crystal can output an integer number for ir led . Frequency Division Factor to 12 . like this 455kHz÷12≈37.9kHz≈38kHz.
But that was in the past, at moment Except 38KHZ， there are have 26 kHz、36 kHz、40 kHz、56 kHz、80 kHz of ir receiver in led market . the single frequency receiver is fastened to specifies frequency. For example the 38khz receiver just only decoding 38khz, the 56khz receiver just only decoding 56khz. With the exception of fixed frequency receiver .there are have wideband receiver(also call variable-frequency or full-frequency).the wideband receiver holds only within certain limitations. which shown that it have stronger function and wider application area.