Isolated RS422 Interface Circuit Diagram Schematic

Isolates RS44 INTERFACE CIRCUIT DIAGRAM SCHEMATIC

Input voltage from aerial voltage DC DC advocate is 12V AC at 800mA accepted and again adapted to DC through a arch rectifier Diode 1A. The voltage achievement of cFigure 1 shows the ambit diagram of RS422 interface. Adapter K1 is affiliated to the consecutive anchorage of the PC, ability to the PC ancillary of the ambit is acquired from the arresting curve DTR and RTS. Positive accumulation is acquired from RTS and abrogating accumulation from the DTR line. Optical abreast is accomplished by optocouplers U1 and U2. Optocoupler U1 accommodate TXD band abreast while optocoupler U2 accommodate RXD band isolation.

The added ancillary of the isolator carries TTL levels. This ancillary is powered by an able dc accumulation amid 9V and 12V ac/dc adapter. IC U5 accommodate 5V adapted achievement and ICs U3 & U4 accommodate the RS422 bus interface. The TXD and RXD curve cachet are provided by abstracts advertence LEDs. The interface has been activated at the baud amount of 19.2k baud.

The adapter K3 accommodate the RS422 bus signals additional the un-regulated dc accumulation output. An RJ45 connector

can be acclimated to accommodate the signals & ability to the added end of the RS422 bus.

The PC RXD pin can alone accept the abstracts back the RS232 handshake curve are set accordingly,

RTS = 1 (at +ve accumulation level)

DTR = 0 (at -ve accumulation level)

For press the pcb files on HP laser printer download the PCBs.zip book and run the Laser.bat book afterwards extracting

from the zip file.

Figure 2 & 3 shows the basic blueprint of the RS422 distinct sided pcb and the clue patterns respectively.onverter ambit can be adapted in the ambit of 0-1000V DC. This aerial voltage DC DC advocate uses the agent as a abject and several added alive apparatus accommodate 555 timer IC, CMOS IC 4001, IC voltage regulator 7805, some NPN transistors and a brace of argumentation MOSFET IRF510 as a final amplifier.

The apparatus of aerial voltage DC to DC advocate is the aforementioned assumption as accounting in antecedent articles. The aberration apparent is this advocate schematic is a aerial achievement voltage and can be arranged.

If a accurate agent mentioned in the schematic is not available, every agent with primary blueprint 117V AC, 6.3V AC CT accessory to work. In this case, advocate ambit operating at a candied atom of the transformer, you may charge to baddest a altered drive frequency.

Be accurate back administration aerial voltages! You are amenable for yourself

Component details of the Part project

1 1 B1 BRIDGE 1A/100V (DIP TYPE)

2 3 C1,C2,C3 100nF CERAMIC

3 1 C4 10uF 16V

4 1 C5 470uF 25V

5 2 D1,D2 1N4148

6 2 D5,D3 LED RED 3mm

7 2 D4,D6 1N4003

8 1 K1 DB9 R/A PCB PLUG

9 1 K2 DC JACK SOCKET

10 1 K3 SIP CON 8 WAY

11 4 R1,R2,R5,R6 1K

12 1 R3 4K7

13 1 R4 470R

14 4 R7,R8,R9,R10 10R

15 2 R13,R11 120R

16 2 R14,R12 680R

17 1 U1 6N137

18 1 U2 CNY17-3

19 2 U3,U4 SN75176B, MAX485

20 1 U5 LM7805

Source http://chaokhun.kmitl.ac.th