–

–

–

–

12

13

Typical Applications

The MS decoder is ideal for replicating button presses for remote control

applications. An example application circuit is shown in Figure 10.

SPDT switches are used to select the baud rate and set the latch mode so

that pull-down resistors are not needed.

The RX_CNTL line can be connected to the PDN line of the receiver or it

can be connected directly to ground.

TX_ID can be connected to a microprocessor or a PC to record the

transmitter identity. Application Note AN-00156 has sample code that

reads the transmitter ID and displays the ID number on a LCD screen.

An LED indicator is attached to the MODE_IND line to provide visual

feedback to the user that an operation is taking place. This line sources a

maximum of 25mA.

The LEARN line is connected to a button that pulls the line high when

pressed. Since the line does not have an internal pull-down resistor, a

100k

Ω resistor is used to pull the line to ground when the button is not

pressed.

The DATA_IN line is connected directly to the data output of the receiver.

To Receiver

2.2k

220

10k

100k

From Receiver

D6

D7

SEL_BAUD0

SEL_BAUD1

GND

GND

LATCH

RX_CNTL

TX_ID

MODE

_IND

D5

D4

D3

D2

VCC

VCC

D1

D0

DATA_IN

LEARN

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

LICAL-DEC-MS001

To Processor or PC

Figure 10: MS Series Decoder Application Circuit

Data Lines D0 through D7 can be connected directly to the external

circuitry that needs to be activated remotely. In this example, D5 is

connected directly to a piezoelectric buzzer. This causes the buzzer to

sound when the D5 line on the encoder goes high. Line D6 activates a

relay through a transistor buffer when it goes high. A buffer like this may be

needed if the load requires more than 25mA of current or a higher voltage

source to activate. The decoder turns on the transistor, which can be

selected to provide the appropriate drive levels to activate the relay.