Silan

Semiconductors

SC5272

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.0

2000.12.31

4

PIN DESCRIPTION

Pin No.

18 PIN

20 PIN

Pin Name

I/O

Description

1~6

1~6

A0~A5

I

Code Address pins No. 0~5. These six tri-state pins are

detected by SC5272 to determine the encoded waveform bit

0 ~bit 5. Each pin can be set to “0”,”1”,”f”(floating).

7~8

10~13

7~8

12~15

A6/D5~A11/D0

I/O

Code Address pins No.6~11/data pins No.5~0. These six

pins are used higher address input bits or data output pins

depending on the versions of SC5272 used.When these

pins are used as address pins, they are tri-state input pins

and can be set to “0”,”1”,”f”.When they are used as output

pins, they are driven to Vcc if (1) the address decoded from

the waveform that was received matches the address setting

at address input pins, and (2) the corresponding data bits

received is a “1” bits. Otherwise, they are driven to Vss.

14

16

DIN

I

Data Input Pin. The encode waveform received is serially fed

to SC5272 at this pin.

15

17

OSC1

I

Oscillator pin 1

16

18

OSC2

O

Oscillator pin 2

A resistor connected between

these two pins determine the

fundamental frequency of SC5272.

17

19

VT

O

Valid Transmission. Active high signal. VT in high state

signifies that SC5272 receives valid transmission waveform.

18

20

Vcc

--

Positive Power Supply

9

9

Vss

--

Negative Power Supply

--

10~11

NC

--

No Connection

FUNCTIONAL DESCRIPTION

The SC5272 decodes the waveform received and fed into the Din pin. The waveform is decoded into code word

that contains the address, data and Sync bits. The decoded address bits are compared with the address set at the

address input pins. If both addresses match for 2 consecutive code words, SC5272 drives:

a). The data output pins whose corresponding data bits is then decoded to be a "1" bit

b). The VT output --to high voltage (high state).

1. RF OPERATION

Code Bits

A code bit is the basic component of the encoded waveform, and can be classified as either an AD(Address/Data)

Bit or a SYNC(Synchronous) Bit.

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 two pulse cycles. Each pulse cycle has 16 oscillating time periods. For further details, please

refer to the diagram below:

a

4a

12a

12a

4a

32a

OSC

bit "0"

bit "1"

bit "f"

Where: a = oscillating clock period .

Bit “ f ” is only available for address bits.