FIELD OF THE INVENTION
The utility model relates to communication technologies, particularly to a RS422-
RS232 communication interface conversion device.
BACKGROUND OF THE INVENTION
RS-422 is differential +/- 5 volt signal and RS-232 is single ended +5 volt signal. In
the communication circuit design, it is often necessary to design RS232 to RS422
circuit. Typical RS232 to RS422 circuit typically use the device as shown in Figure 1.
RS422 interface, say, R is the receiver, D is the transmitter. DI output signal, RO
received signal, RE receives the transceiver enable control signal, DE for the
transceiver to send the enable control signal. During use of the transmitter must be
strictly controlled D, it is only allowed when the output signal DI has to be able to
open the transmitter D.
R is the transceiver which convert differential signal (RS-422) to single ended signal
RO which then transmitted to transceiver, which converts single ended signal to RS-
232 format. A Regulator IC of 12 volt to 5 volt is used for safety purpose. The
transmitter D in the sending state, and DI signals to TTL level input node to be sent
to the transmitter D, D transmitter was received from the TTL DI level is converted
into a differential a signal is sent to the data bus.
SUMMARY OF PRESENT INVENTION
In accordance with one aspect of the utility model of communication interface
conversion device, characterized in that, by the RS-232 interface, the relay unit and
the RS422 interface in series, the relay unit includes a transmitting section and the
relay receiving relay section.
In accordance with second aspect of the utility model of communication interface
conversion device, regulator IC is used to provide internal 5 volt, to protect the
model from voltage fluctuation.
In accordance with another aspect of the utility model of communication interface
conversion device, the utility model has beneficial effects, simple structure, low cost,
better reliability and robustness, and noise reduction features.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 : Shows the block diagram of RS-422 to RS-232 converter.
Figure 2&3 : Shows the Block diagram of Transceiver for Transmitter and Receiver.
DETAILED DESCRIPTION
RS-232 serial interface
RS-232 is the most common type of serial interface, it was the standard communication
before the PS2 and USB become popular in the computer industry, you use to connect
mouse, modem and printer to RS-232 serial interface. RS-232 only allows for one
transmitter and one receiver on each line. RS-232 also use a Full-Duplex transmission
method. RS-232 can transmit up to 1Mbps with maximum distance up to 50 ft.
RS-422 serial interface
RS422 is an improved version of RS232, it uses twisted pair cable to reduce the noise,
and it uses signaling balancing to transmit data, so what is signal balanced – It uses a
voltage-difference between the two lines as an indication of the signal value, with this
method the data is able to transmit for longer distance with faster data rates, with
RS422 the data can transmit up to 10 Mpbs at 50 feet or 100 Kbps at 4000 feet. RS422
is capable of multi-drop capability, it limits up to 10 slaves in the data line.
In this circuit, R is the transceiver which convert differential signal to single ended signal
RO which then transmitted to transceiver, which converts single ended signal to RS-232
format. RS232 interface RS232 level of the received signal, through the RS232
interface is converted to TTL level signals. The transmitter D in the sending state, and
DI signals to TTL level input node to be sent to the transmitter D, D transmitter was
received from the TTL DI level is converted into a differential a signal is sent to the data
bus.

WE CLAIMS:-
Accordingly, the description of the present invention is to be considered as illustrative only and is for the purpose of teaching those skilled in the art of the best mode of carrying out the invention. The details may be varied substantially without departing from the spirit of the invention, and exclusive use of all modifications which are within the scope of the appended claims is reserved. We Claim

1. RS422-RS232 communication interface conversion device, characterized in that, by the RS232 interface Transceiver (Relay) unit and a RS422 interface connected in series.
2. Model according to claim 1, comprising regulator IC for 12 volt to 5 volt conversion.
3. Model according to claim 1&2, is Power protected.
4. Model according to claim 1&2, is easy to fabricate and requires less electrical parts. ,TagSPECI:As per Annexure-II