Silan
Semiconductors
SC9012
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.1
2002-02-28
1
INFRARED REMOTE CONTROL
TRANSMITTER
DESCRIPTION
SC9012 is an infrared remote control transmitter utilizing CMOS
Technology specially designed for use on infrared remote control
applications. It is capable of controlling 32 function keys and 6
double keys. Each system has a maximum of 8 commands; thus,
SC9012 can provide up to a total of 256 commands.
The pin assignments and application circuit are optimized for easy
PCB Layout and cost saving advantage. SC9012 is housed in a 20-
pins SO package.
FEATURES
* CMOS Technology
* Low Power Consumption
* Built-in Oscillation Circuit
* Least External Components
* 32 Function Keys
8 Customer Codes
Up to 256 Commands
* 6 Double Function Keys
* LED Indication of Transmission
SOP-20
ORDERING INFORMATION
SC9012
SOP-20 Package
APPLICATIONS
* Infrared Remote Control Transmitter
Equipment
* Television Remote control Equipment
* VCR Remote control Equipment
* VCD, Audio Equipment
PIN CONFIGURATION
BLOCK DIAGRAM
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
KI0
KI1
KI2
KI3
D
OUT
V
DD
NC
OSCO
OSCI
Vss
SEL
KO0
KO1
KO2
KO3
KO4
KO5
KO6
KO7
LMP
SC9012
8
9
OSC Circuit
Frequency
Division Circuit
Timing Generation
Customer Code
Latch Circuit
Key Input Scan Circuit
1
2
3
4
Output Circuit
Carrier
Generation Circuit
Control Circuit
Digital Circuit
19
18
17
16
15
14
13
12
Key Output Scan Circuit
10
6
20
7
5
11
NC
OSCI
D
OUT
LMP
V
SS
V
DD
KI0 KI1 KI2 KI3
KO0 KO1 KO2 KO3 KO4 KO5 KO6 KO7
SEL
OSCO
Silan
Semiconductors
SC9012
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.1
2002-02-28
2
ABSOLUTE MAXIMUM RATING
(Tamb=>25
C
Characteristic Symbol
Value
Unit
Supply Voltage
V
DD
-0.3 ~ 5.0
V
Input Voltage With Respect To V
ss
V
IN
V
ss
-0.3
~
V
DD
+0.3
V
Output Current
I
OUT(REO)
-20
mA
Power Dissipation
Pd
300
mW
Storage Temperature
Tstg
-40 ~ +125
C
Operating Temperature
T
OPR
-20 ~ +75
C
ELECTRICAL CHARACTERISTICS
(Tamb=25
C,V
DD
=3V)
Parameter Symbol
Test
conditions
Min
Typ
Max
Unit
Operating supply Voltage
V
DD
All Function Operating
2.0
--
4.0
V
Operating Supply Current
I
DD
f
OSC
=455 kHz
--
--
1
mA
Stand-By Current
I
SB
All Keys Off Stops. Oscillation
Output Floating.
1
A
Output High Level Current (Dout)
I
OH
V
OH
=1.5V, V
DD
=3V
-10
--
--
mA
Output Low Level Current (LMP)
I
OL
V
OL
=1.5V, V
DD
=3V
5
--
--
mA
Input High Level Voltage (KI)
V
IH
V
DD
=3V
0.7 V
DD
V
DD
V
Input Low Level Voltage (KI)
V
IL
V
DD
=3V
0
0.3 V
DD
V
Oscillation Frequency
fosc
--
400
455
600
kHz
Input Pull-down Resistor (KI)
R
ON
V
DD
=3V
100
300
500
k
PIN DESCRIPTION
Pin No.
Symbol
I/O
Description
1~4
KI0~KI3
I
Key Scan Input Pins. Each pin has a built-in pull-down resistor
5
D
OUT
O
Infrared LED Driving Output Pin
6
V
DD
--
Positive Power Supply
7
NC
--
No Connection. (When used, Suggest to connected with V
DD
)
8
OSCO
O
Oscillator Output Pin
9
OSCI
I
Oscillator Input Pin
10
V
SS
--
Negative Power Supply
11
LMP
O
LED Display Output Pin
12~19
KO0~KO8
O
Key Scan Output Pins
20
SEL
I
Custom Code Selection Pin
Silan
Semiconductors
SC9012
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.1
2002-02-28
3
FUNCTIONAL DESCRIPTION
1. OSCILLATION CIRCUIT
An oscillator circuit may be constructed by connecting a 480kHz or 455kHz Crystal Resonator and two capacitors
between OSCO and OSCI. Please refer to the follow diagram. Unless the keys are being operated, the oscillation is
normally stopped. Thus, power consumption is considerably reduced.
OSCO
OSCI
100pf
100pf
9
8
SC9012
455kHz
2. OSCILLATION FREQUENCY
The oscillator frequency is 455kHz, passed by a 12 division frequency circuit, can get a 37.9 ~ 39.2 frequency; 1/3
duty carrier. In addition, The oscillator frequency divided by 256, can get the basic system work time (1.78kHz). The
relation of carrier frequency (fc), internal work time period (Tm) and oscillator frequency (fosc) is given below:
fc =
1/12
fosc
duty
1/3
Tm = 256 / fosc
Tm
the width of a high level pulse
.
3. KEY
MATRIX
Key Inputs -- KI0~KI3 of SC9012 have built-in pull-down resistors, which combined 32 keys matrix with Key Outputs
--KO0~KO7. Except the stated 6 double keys, Pressing other keys that are NOT intended for the double key
operation do NOT generate any output. Please refer to the follow diagram for the keys input matrix of SC9012.
5
1
13
9
21
17
29
25
6
2
14
10
22
18
30
26
7
3
15
11
23
19
31
27
8
4
16
12
24
20
32
28
KI0
KI1
KI2
KI3
KO
0
KO
1
KO
2
KO
3
KO
4
KO
5
KO
6
KO
7
Silan
Semiconductors
SC9012
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.1
2002-02-28
4
4. CUSTOMER CODE
There are 8 customer codes, can be selected by using the SEL pin connected with any pin of "KO0 ~ KO7". Please
refer to follow diagram:
Connected with
SEL
System Code
(S2 S1 S0
KO0
0
0
0
KO1
0
0
1
KO2
0
1
0
KO3
0
1
1
KO4
1
0
0
KO5
1
0
1
KO6
1
1
0
20
19
18
17
16
15
14
13
12
SEL
KO
0
KO
1
KO
2
KO
3
KO
4
KO
5
KO
6
KO
7
KO
2
connected with SEL, the value of S2, S1, S0 is 0,1,0
KO7
1
1
1
The Custom Code consists of 8 bits
S0
S1
S2
S3
S4
S5
S6
S7
Among these, S0, S1, S2 can be selected with SEL Pin and any pin of "KO0 ~ KO7"; Bit S3 has a fixed value of "1";
Bits S4 ~ S7 have a fixed value of "0".
5. TRANSMISSION CODE
S0 S1 S2 S3
S5
S4
S6 S7
D0 D1 D2 D3 D4
D0 D1 D2 D3 D4 D5 D6 D7
D5 D6 D7
Leader
Code
Custumer Code
Customer Code
Key Data Code
Key Data Code
S0 S1 S2 S3
S5
S4
S6
S7
Refer to the above diagram, the transmission code consists of leader code, customer code, and key data code.; The
leader code consists of a 4.5 ms carrier waveform followed by a 4.5 ms OFF waveform. The 8-bits customer code
transmitted two times; The 8-bits key data code transmitted two times also, first is the origin code; second is the
inverse code.
The code uses the PPM (Pulse Position Modulation ) Method, with "0"and "1" differentiated by the time between
pulses.
Silan
Semiconductors
SC9012
HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD
Rev: 2.1
2002-02-28
5
The waveforms of leader code, bit "0" and bit "1" refer to follow diagram:
4.5ms
4.5ms
Tm
Tm
Tm=0.56ms
Tm
3Tm
Leader
Code
Bit"0"
Bit"1"
6. DOUBLE KEY OPERATION
There are 6 double keys operation, such as K21 connected with K22 ~ K24; K25 connected with K26 ~ K28, refer to
the follow table:
The Primary Key
The Secondary Key
D0
D1
D2
D3
D4
D5
D6
D7
K22
1
0
1
0
1
1
0
0
K23
0
1
1
0
1
1
0
0
K21
K24
1
1
1
0
1
1
0
0
K26
1
0
0
1
1
1
0
0
K27
0
1
0
1
1
1
0
0
K25
K28
1
1
0
1
1
1
0
0
When any of the double or multiple key combinations are pressed, except the 6 keys mentioned above, there is no
output.
In addition, Double Key Operation is useful for tape deck recording operation. Press the K21 or K23 key at the first
then followed by the secondary key such as K22~K24; K26~K28.
Please refer to the follow diagram:
1. Double Key Operation available
K
21
(K
25
) Key Code Transmission
T>126ms
K
21
(K
25
)
K
22
~K
24
K
26
~K
28
K
22
~K
24
+D
5
(1) Key Code Transmission
(K
26
~K
28
+D5(1))
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