Silan

Semiconductors

SC5260

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0

2000.12.31

4

FUNCTIONAL DESCRIPTION

SC5260 encodes the code address and data set at A0~A7, A8/D3, A9/D2, D1 and D0 into a special waveform

and outputs it to the DOUT when any of the data pins is tied to high. This waveform is fed to the RF Modulator for

transmission. The transmitted radio frequency is received by the RF demodulator and reshaped into the special

waveform. SC5270 (or SC5272) is then used to decode the waveform and set the corresponding output pin(s).

Thus completing a remote control encoding and decoding function.

1. RF Operation

1) Code Bits

A Code Bits is the basic component of the encoded waveform, and can be classified as either an

AD

(Address/Data) Bit or a SYNC (Synchronous) Bit.

•Address/Data (AD) Bit Waveform

An AD Bit can be designated as Bit “0”, “1”, or “f” if it is in low, high or floating state respectively. One bit

waveform consists of 2 pulse cycles. Each pulse cycle has 512 oscillating clock periods. For further details, please

refer to the diagram below:

1 bit = 1024

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128

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Osc

Bit "0"

Bit "1"

Bit "f"

Floating

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384

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128

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Where:

α = Oscillating Clock Period

•Synchronous (SYNC.) Bit Waveform

The Synchronous Bit Waveform is 4 bits long with 1/8 bit width pulse. Please refer to the diagram below:

1/8bit width= 128

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4 bit width = 4096

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Note: 1 bit = 1024

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