ELM622
Infrared Remote Interpreter
Description
The ELM622 is an interface circuit for converting
infrared control codes to an eight bit serial format.
This device is well suited to applications that only
require occasional input from humans, or where a
hidden interface is desired.
When connected to a standard infrared receiver
module, the ELM622 continually scans the data
stream for Sony™ television control codes. If
detected, the codes are retransmitted serially, with
hardware handshaking. This data can then be used
directly by logic circuits, or suitably buffered and
transmitted on a standard RS232 connection.
For convenience, some of the control codes are
translated to their ASCII equivalents before
retransmission, allowing direct display of the
common control signals on an ASCII terminal.
Many products that currently rely on a keyboard
for input can benefit from the small size and
simplicity that an ELM622 provides, and several
others are likely to benefit from the at-a-distance
control that this circuit offers.
Features
• Low power CMOS design - typically 1mA at 5V
• RS232 formatted output at 9600 baud
• Hardware handshaking provided
• Signal received output for visual feedback
• Simple interface to standard receiver modules
• Works with universal TV remote transmitters
• Reset output on command
• High current drive outputs - up to 25 mA
Connection Diagram
PDIP and SOIC
(top view)
V
DD
Tx
1
2
3
4
8
7
6
5
V
SS
Reset
LED
IRRx
Applications
• Alternative to keyboard interface
• Hidden security system control
• Non-contact device control for safety
• Home automation receiver
RTS
CTS
Block Diagram
IRRx
5
Data
Decoder
Code
Translator
RS232
Encoder
2
Tx
3
RTS
CTS
LED
6
4
99999
Detector
100ms
Pulse
Generator
7
Reset
ELM622DSA
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