RS232 to TTL/CMOS 5V Converter

The TTL-232-1 is an industrial-grade (wide temperature range with surge & static protection) port-powered bi-directional RS232 to TTL converter, which can be used to convert RS232 to 5V TTL/CMOS compatible levels and vice versa.  This industrial-grade RS232 to TTL converter operates within a wide temperature range (-40ºF to 185ºF / -40ºC to 85ºC), and features 600W surge protection and 15kV static protection.  The unit is powered from the RS232 data line, and therefore, no external power or RTS, DTR is required.

Declaration of Conformity | RS232 to TTL/CMOS 5V Converter data sheet

FEATURES (INDUSTRIAL RS232 TO TTL CONVERTER)

- Converts RS232 to TTL 5V and vice versa.
- Industrial grade with wide temperature range (-40ºF to 185ºF / -40ºC to 85ºC),
  surge (600W) and static protection (15kV).
- Port-powered, no external power or RTS, DTR required.
- Plug and play (Hot-pluggable, Data format Auto-sensing & Self-adjusting).
- Built-in surge protection, static protection and circuit protection.
- Surface Mount Technology manufactured to ISO-9001 standards.
- CE certified: strictly certified by world-class lab TUV.
- 5-year manufacturer's warranty.    

PRODUCT PHOTOS (INDUSTRIAL RS232 TO TTL CONVERTER)

SPECIFICATIONS (INDUSTRIAL RS232 TO TTL CONVERTER)

TTL SIGNAL LEVELS

CONVERTER CONNECTOR / TERMINAL BLOCK PINOUTS

RS232 Side

Pin 1 4 6 7 8 2 3 5 Signal DCD DSR DTR CTS RTS TX RX GND Function Tied Tied TX RX GND

Note: Some software requires handshake line acknowledgements. To satisfy the requirements, our converter's handshake lines are tied together (DCD, DTR, and DSR tied together, and RTS and CTS tied together). Therefore, you don't have to modify your existing software.

DB-9 Female (view from front)

Terminal Block Side

Pin 1 3 5 9 Terminal Block TX RX GND +5V Function TTL Out TTL In GND +5V measurement

Note: The TTL-232-1 comes with a 4-way terminal block for easy wire connections. However, you may choose not to use the terminal block provided and simply follow the above table for pin assignments.
DB-9 Male (view from front) / Terminal Block

CONNECTIONS (INDUSTRIAL RS232 TO TTL CONVERTER)

Figure 1: TTL-232-1 Connection Diagram

TROUBLESHOOTING INSTRUCTIONS FOR RS232 TTL CONVERTER

1) Port power measurement

Measure pin +5V and GND with a voltmeter, and be sure that it is around +5VDC (when RS232 port is connected). Otherwise, please check the power on the RS232 port to which the converter is connected (as shown below).

Note: The port-powered RS232 TTL converter (TTL-232-1) requires a -7 to -15VDC on the TX line (Pin 3 on DTE or Pin 2 on DCE) of the RS232 port to which the converter is connected. You can connect TTL-232-1 to a DTE device which comes with a DB-9 Male connector; however, if it is a DCE device, you will need to swap Pin 2 and 3 before connecting to the converter.

2) Loopback Test

Connect a TTL-232-1 to your PC's COM port and short TX and RX on the TTL terminal block (as shown above). Run 232Analyzer FREE version software on your computer. Select "ASCII" for both the Send and Receive data formats. Then send command and/or string such as "CommFront" from the 232Analyzer software. You should receive an echo of the command/string sent ("CommFront"). By performing a simple loopback test like this, you can test both the transmitter and receiver of the converter. This is very helpful when you are in doubt about the performance of your converter.

Screenshot: Send/receive commands from 232Analyzer software.

232Analyzer is an advanced RS232 Serial Protocol Analyzer software that allows you to control, monitor and analyze serial port (RS232 / RS485 / RS422 / TTL, etc.) activities. Not just the data, it also allows you to monitor or change RS-232's line states: RTS, CTS, DTR, DSR, DCD, and RI. The FREE version (no time limitation) can be downloaded from here.