Silan
Semiconductors

SC6121

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.2

2002-02-28

INFRARED REMOTE CONTROL
TRANSMITTER

DESCRIPTION

The SC6121 is a remote control transmitter utilizing CMOS

Technology specially designed for use on infrared remote control

applications. It is capable of controlling 32 function keys and 3

double keys. SC6121 is housed in a 20-pins SO package.

FEATURES

* CMOS Technology

* Low Operating Voltage (V

=2.0~5.5V)

* Using SEL pin, SC6121 can support 64+6 function codes

* Customer Code can be selected

APPLICATIONS

* TV and VCR

* Audio Equipment

* Cable TV Tuner

* Cassette Deck

* Air Conditioner

* VCD and DVD ROM/Player

* Moniputer/Multi-Media Personal Computer System

SOP-20

ORDERING INFORMATION

SC6121-001
SC6121-002

ROM Content=0
Custom Version

PIN CONFIGURATION

KI0

KI1

KI2

KI3

REM

SEL

OSCO

OSCI

Vss

CCS

KI/O0

KI/O1

KI/O2

KI/O3

KI/O4

KI/O5

KI/O6

KI/O7

LMP

SC6121

Silan
Semiconductors

SC6121

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.2

2002-02-28

BLOCK DIAGRAM

Key

Input
Scan

Circuit

OSC Circuit

Timing Generation

&Control Circuit

Code Generation Circuit

Key Input/Output Scan Circuit

Optput

Control

Circuit

KI0

KI1

KI2

KI3

KI/O0 KI/O1 KI/O2 KI/O3 KI/O4 KI/O5 KI/O6 KI/O7

CSS

LMP

REM

SEL

OSCI

OSCO

Vss

ABSOLUTE MAXIMUM RATING

(Tamb=25

�

unless otherwise specified)

Characteristic Symbol Value

Unit

Supply Voltage

6.0

Input Voltage

-0.3~VDD

Power Dissipation

250

Storage Temperature

stg

-40~+125

�

Operating Temperature

opr

-20~+75

�

RECOMMENDED OPERATING CONDITIONS

(Tamb=25

�

unless otherwise specified)

Characteristic Symbol

Min.

Typ.

Max.

Unit

Supply Voltage

2.0

3.0

3.3

Oscillation Frequency

fosc

400

455

500

KHz

Input Voltage

Custom Code Select Pull-Up

Resistance

Rup

100

Silan
Semiconductors

SC6121

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.2

2002-02-28

ELECTRICAL CHARACTERISTICS

(Tamb=25

�

=3.0V,unless otherwise specified)

Parameter Symbol

Test

conditions

Min

Typ

Max

Unit

Supply Voltage

2.0

3.0

5.5

Current Consumption 1

DD1

Fosc =455KHz

0.1

1.0

Current Consumption 2

DD2

Fosc =STOP

1.0

�

REM High Level Output Current

OH1

Vo=1.5V

-5.0

-8.0

REM Low Level Output Current

OL1

Vo=0.3V

�

LMP High Level Output Current

OH2

Vo=2.7V

-15

-30

�

LMP Low Level Output Current

OL2

Vo=0.3V

1.5

KI High Level Input Current

IH1

=3.0V

�

KI Low Level Input Current

IL1

=0V

-0.2

�

KI High Level Input Voltage

IH1

0.7 V

KI Low Level Input Voltage

IL1

0.3 V

KI/O High Level Input Voltage

IH2

0.7 V

KI/O Low Level Input Voltage

IL2

0.4

KI/O High Level Input Current

IH2

=3.0V

�

KI/O Low Level Input Current

IL2

=0V

-0.2

�

KI/O High Level Output Current

OH3

Vo=2.5V

0.5

1.5

KI/O Low Level Output Current

OL3

Vo=1.7V

1.5

2.5

CCS Low Level Input Voltage

IH3

1.1

CCS High Level Input Current

IH3

Pull Up V

=3.0V

0.2

�

CCS Low Level Input Current

IL3

Pull Up V

=0V

-3

-15

�

CCS High Level Input Current

IH4

Pull Down V

=3.0V

�

CCS Low Level Input Current

IL4

Pull Down V

=0V

-0.2

�

PIN DESCRIPTION

Pin No.

Symbol

I/O

Description

1~4

KI0~KI3

Key Input Pin Nos. 0~3

REM

Data Output Pin

Power Supply

SEL

Select Pin

OSCO

Oscillator Pin

OSCI

Oscillator Pin

Vss

Power Supply

LMP

Output LED Indicator

19~12

KI/O0~KI/O7

I/O

Key Input/Output Pin Nos.0~7

CCS

Custom Code Scan Input Pin

Silan
Semiconductors

SC6121

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.2

2002-02-28

FUNCTIONAL DESCRIPTION

1. TRANSMISSION CODE

The transmission code consists of a leader code, 16-bits custom codes, and 8-bits data codes. The inverse

code of the data code is also sent simultaneously. The following diagram shows this one frame construction.

C0 C1 C2 C3

C6 C7

D0 D1 D2 D3 D4

D0 D1 D2 D3 D4 D5 D6 D7

C0'

D5 D6 D7

Leader

Code

Custom Code

8 bits

Custom Code'

8 bits

Key Data

8 bits

Key Data

8 bits

The leader codes consist of a 9ms carrier waveform followed by a 4.5ms OFF waveform. It is used as the leader

for the following code. Thus, when reception is configured by a microcomputer, the time relationship between the

reception detection and other processes can be managed efficiently. The code uses the PPM (Pulse Position

Modulation) Method, with "0" and "1" differentiated by the time between pulses. Each code consists of 8 bits, and

simultaneous transmission of the inverse code allows configuration of a system with an extremely low error rate.

2. KEY INPUT MATRIX

The Key Input Matrix of SC6121 if given below:

KI0

KI1

KI2

KI3

I/O

3. KEY INPUT

A total of 32 keys can be connected by SC6121 Key Input Pins--KI0~KI3 and the Timing Signal Output Pins

KI/O0~KI/O7.

Double Key Operation is possible for only Key No.21 in combination with other keys connected to the KI/O5 line

namely: Key No.22,23 or 24.thus, only the following key combinations may be used for the double key operation:

1. Key Nos.21 and 22

2. Key Nos.21 and 23

3. Key Nos.21 and 24

Silan
Semiconductors

SC6121

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.2

2002-02-28

Pull-down resistors are connected between the Key Input and Vss Pins. When more than one key (except the

double key combinations: K21+22, K21+23, K21+24) are pressed simultaneously, the transmission output stops.

Two key inputs are regarded as being pressed simultaneously when the time interval between these two key

entries is less than 36ms.

The order of priority given to two key inputs with a time interval of more than 36ms is on a First-Pressed-First-

Served or Longer-Pressed-First-Served Basis.

When a key is pressed, the custom and data codes are read. 36ms later, the Remote (REM) Output is activated.

When the key is kept depressed during this 36ms, one transmission is outputted. If the key is depressed for more

than 108ms, then the only the leader code is transmitted continuously.

4. DOUBLE KEY OPERATION

Double Key Operation is useful for operations such as tape deck recording. The following table shows the Key

Data corresponding to the double keys pressed. Also refer to the Key Input Section.

The Double Key operation forms are as follows:

Key D0 D1 D2 D3 D4 D5 D6 D7

K21+K22

0/1

K21+K23

0/1

K21+K24

0/1

Note: D7=1 when SEL is connected to V

, or D7=0 when SEL is connected to V

K21

K22 to 24

t >126ms

K21 Transmission

D5+K22 to 24

Transmission

OPERATION

K21

K22 to 24

push

36ms< t <126ms

K21 Transmission

No Transmission

NO OPERATION

K21

K22 to 24

-36ms< t < 36ms

No Transmission

NO OPERATION

K21

K22 to 24

t >126ms

NO OPERATION

K22 to 24 Transmission

No Transmission

Silan
Semiconductors

SC6121

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.2

2002-02-28

5. REMOTE OUTPUT WAVEFORMS

The Remote Output Waveforms are given in the diagram below:

Ex. fosc=455KHz

Min.

36ms

58.5 to 76.5ms

108ms

9ms

4.5ms

Custom Code

8bits

Custom

Code

Data Code

8bits

Data Code

8bits

13.5ms
Leader

Code

18ms to 36ms

27ms

58.5ms to 76.5ms

9ms

4.5ms

13.5ms

2.25ms

1.125ms

0.56ms

9ms

11.25ms

0.56ms

2.25ms

8.77

�s

26.3

�s

9ms to 0.56ms

Carrier Frequency---Fc=fosc/12=38KHz

Carrier

Key ON

Silan
Semiconductors

SC6121

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.2

2002-02-28

SC6121 KEYS DATA CODE

The Keys Data Code is given in the table below.

Connection Data

Code

Key

No.

KI0 KI1 KI2

KI3 KI/O

D4 D5 D6 D7

�

0/1

�

0/1

�

0/1

�

KI/O0

0/1

�

0/1

�

0/1

�

0/1

�

KI/O1

0/1

�

0/1

K10

�

0/1

K11

�

0/1

K12

�

KI/O2

0/1

K13

�

0/1

K14

�

0/1

K15

�

0/1

K16

�

KI/O3

0/1

K17

�

0/1

K18

�

0/1

K19

�

0/1

K20

�

KI/O4

0/1

K21

�

0/1

K22

�

0/1

K23

�

0/1

K24

�

KI/O5

0/1

K25

�

0/1

K26

�

0/1

K27

�

0/1

K28

�

KI/O6

0/1

K29

�

0/1

K30

�

0/1

K31

�

0/1

K32

�

KI/O7

0/1

Note: D7=1 when SEL is connected to V

, or D7=0 when SEL is connected to V

Silan
Semiconductors

SC6121

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.2

2002-02-28

TYPICAL APPLICATION CIRCUIT

SC6121

�

IR LED

LED

455KHz

200pF

I
N

00K

�

00K

�

00K

�

00K

�

00K

�

00K

�

00K

�

00K

�

For Custom
Code Selection

KI0

KI1

KI2

KI3

KI/O0

KI/O2

KI/O3

KI/O4

KI/O5

KI/O1

KI/O6

KI/O7

CCS

VSS

SEL

REM

LMP

OSCO

OSCI

VCC

0.1

470

�

270

�

Note:1. Two capacitance connect with Vcc should as near as possible.

2. The line between two capacitance and Vcc and ground should as short as possible.

Silan
Semiconductors

SC6121

HANGZHOU SILAN MICROELECTRONICS JOINT-STOCK CO.,LTD

Rev: 1.2

2002-02-28

PCB WIRE LAYOUT SCHEMATIC:

Transmitting tube output ground line

The transmitting tube ground line and IC ground line should
layout separated or overstriking ground line.

The above IC only use to hint, not to specified.

Note:

* In wire layout, the power filter capacitor should near to IC.

* In wire layout, should avoid power line and ground line too long.

* Recommended infrared transmit unit and IC ground line should layout separated, or overstriking lines.

* The emitter of triode connect 1

�

resistor at least.

* Recommended triode use 9014.

Электронный компонент: SC6121