Silan
Semiconductors
REMOTE CONTROL DECODER
DESCRIPTION
The SC5272 is a remote control decoder paired with SC5262
utilizing CMOS technology. It has a maximum of 12-bits of tri-state
address pins providing up to 531,441(or 3
12
) address codes;
thereby, drastically reducing any code collision and unauthorized
code scanning possibilities.
SC5272
DIP-18
FEATURES
* Low power consumption and very high noise immunity
* Up to 12 tri-state code address pins or 6 data pins
* Wide operating voltage range(Vcc=3V ~ 15V)
* Single resistor oscillator
* Latch or Momentary output type
SOP-20
DIP-20
APPLICATION
* Home/automation security system
* Remote control toys or for industrial use
* Remote control fan
* Garage door controller
ORDERING INFORMATION
SC5272X-XX
Data Bits:
0: 0 data bit(can be omitted)
2: 2 data bits
3: 3 data bits
4: 4 data bits
5: 5 data bits
6: 6 data bits
L: Latch Type
M: Momentary Type
S: SOP-20 Package
D: DIP-20 Package
Omitted: DIP-18 Package
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 1.0
2000.12.31
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Silan
Semiconductors
PIN CONFIGURATION
SC5272
A0
A1
A2
A3
A4
A5
A6
A7
Vss
NC
1
Vcc
VT
OSC1
OSC2
A0
A1
1
Vcc
VT
A3
A4
A5
A6
A7
Vss
NC
SC5272-M2/L2
A2
OSC1
OSC2
Din
D0
D1
A9
A8
NC
SC5272
Din
A11
A10
A9
A8
NC
A0
A1
A2
1
Vcc
VT
OSC1
A0
A1
A2
A3
18 Pin
Package
20 Pin
Package
A4
A5
A6
A7
Vss
NC
1
Vcc
VT
OSC1
SC5272-M3/L3
SC5272-M4/L4
A3
A4
A5
A6
A7
Vss
NC
OSC2
Din
D0
D1
D2
A8
NC
OSC2
Din
D0
D1
D2
D3
NC
A0
A1
A2
1
Vcc
VT
OSC1
A0
A1
A2
A3
A4
A5
D5
D4
Vss
NC
1
Vcc
VT
OSC1
SC5272-M5/L5
SC5272-M6/L6
A3
A4
A5
A6
D4
Vss
NC
OSC2
Din
D0
D1
D2
D3
NC
OSC2
Din
D0
D1
D2
D3
NC
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 1.0
2000.12.31
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Silan
Semiconductors
BLOCK DIAGRAM
OSC2
OSC1
SC5272
VT
17
18 Vcc
Sync.
Detect
Control
Logic
Compare
Logic
9 Vss
Data
Detect
15
16
Output Logic
OSC
System
Timing
Tri-stateAddress Data Detect
1
A0
2
A1
3
A2
4
A3
5
A4
6
A5
7
A6
8
10
11
12
13
14
Din
A7 A8 A9 A10 A11
The Pin configurations are for DIP-18 package and are also some different with the SC5272 suffix
(please refer to the Pin Configuration)
ABSOLUTE MAXIMUM RATINGS
(Ta=25°C )
Characteristic
Supply Voltage
Input Voltage
Output Voltage
Maximum Power Dissipation(Vcc=12V)
Operating Temperature
Storage Temperature
Symbol
Vcc
Vi
Vo
Pa
Topr
Tstg
Value
-0.3 ~ 16.0
-0.3 ~ Vcc+0.3
-0.3 ~ Vcc+0.3
300
-20 ~ +70
-40 ~ +125
Unit
V
V
V
mW
°C
°C
ELECTRICAL CHARACTERISTICS
(Ta=25°C,Vcc=12V,unless otherwise specified)
Characteristic
Supply Voltage
Supply Current
Symbol
Vcc
Icc
Test Condition
Vcc=12V,OSC stops
A0~ A11 Open
Vcc=5V,V
OH
=3V
Vcc=8V,V
OH
=4V
Vcc=12V,V
OH
=6V
Vcc=5V,V
OL
=3V
Vcc=8V,V
OL
=4V
Vcc=12V,V
OL
=6V
Min
3
Typ.
0.02
Max
15
0.3
Unit
V
µA
mA
mA
mA
mA
mA
mA
V
V
Dout Output driving Current
I
OH
Dout Output sinking Current
Input High Voltage
Input Low Voltage
I
OL
V
IH
V
IL
-3
-6
-10
2
5
9
0.7Vcc
0
Vcc
0.3Vcc
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 1.0
2000.12.31
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Silan
Semiconductors
PIN DESCRIPTION
Pin No.
18 PIN
20 PIN
1~6
1~6
SC5272
I/O
I
Pin Name
A0~A5
Description
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).
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.
Data Input Pin. The encode waveform received is serially fed
to SC5272 at this pin.
A resistor connected between
Oscillator pin 1
these two pins determine the
Oscillator pin 2
fundamental frequency of SC5272.
Valid Transmission. Active high signal. VT in high state
signifies that SC5272 receives valid transmission waveform.
Positive Power Supply
Negative Power Supply
No Connection
7~8
10~13
7~8
12~15
A6/D5~A11/D0
I/O
14
15
16
17
18
9
--
16
17
18
19
20
9
10~11
DIN
OSC1
OSC2
VT
Vcc
Vss
NC
I
I
O
O
--
--
--
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:
32a
a
OSC
bit "0"
bit "1"
bit "f"
4a
12a
12a
4a
Where: a = oscillating clock period .
Bit “ f ” is only available for address bits.
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 1.0
2000.12.31
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Silan
Semiconductors
SC5272
1/8 bit width=4a
The Synchronous bit waveform is 4 bits long with 1/8 bit width pulse. Please refer to the diagram below:
4 bit width=128a
Note: 1bit =32a
Code word
A group of Code Bits is called a Code Word. A Code Word consists of 12 AD bits followed by one Sync. Bit. The
12 AD bits are interpreted as either address or data bits depending on the SC5272 version used. Please refer to
the diagram below:
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
SYNC
Single Resistor Oscillator
The Build-in oscillator circuitry of SC5272 allows a precision oscillator to be constructed by connecting an
external resistor between OSC1 and OSC2 pins. For SC5272 to decode correctly the received waveform, the
oscillator frequency of SC5272 must be 2.5 ~8 times that of transmitting SC5262. It is a good practice to center the
SC5272 oscillator frequency in the window to gain best window margin at both sides. The typical oscillator
frequency with various resistor values for both SC5262 and SC5272 are shown below:
Encoder OSC Frequency
100
1000
Decoder OSC Frequency
R=100k
R=240k
R=510k
R=1M
Frequency (kHz)
R=2M
R=3.3M
10
Frequency (kHz)
100
R=510k
R=1M
R=2M
R=4.7M
10
1
0
3
6
9
12
15
1
0
3
6
9
12
15
Supply Voltage (V)
Supply Voltage (V)
Suggested Oscillator resistor values are shown below:
SC5262
4.7M
3.3M
1.2M
SC5272
820k
680k
200k
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 1.0
2000.12.31
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