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PT2262 V3.8

- 7 -

September, 2008

Remote Control Encoder

PT2262

IR OPERATION

In the IR Type of Operation, the functions are similar to the above descriptions except for the output

waveform that has a carrier frequency of 38KHz. Details are as follows:

CODE BITS

The Code Bits are further modulated with a 38KHz carrier frequency and can be “0”, “1” or “f” bit. Their

waveforms are shown in the diagram below.

160

λ

20

λ

60

λ

20

λ

620

λ

OSC

0

1

f

Sync

Note :

λ = 2 clock lengths

CODE WORD

A Code Word is made up of code bits and the format is the same as that of the RF Code Word.

CODE FRAME

Likewise, a Code Frame is made up of Code Words and the format is the same as that of RF Type of

Operation.

OSCILLATOR

The Oscillator Frequency for the IR Type of Operation is twice the carrier frequency. Thus, the

oscillator frequency should be kept at 76 KHz. A 430K ~ 560K

Ω oscillator resistor between OSC 1 and

OSC 2 pins is recommended. It should be noted that the carrier is a 50% duty cycle frequency.