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Four-Channel RS-232 to TTL/CMOS Converter &(
Model 232LPTTL
Description
The 232LPTTL converts RS-232 to TTL/CMOS compatible levels. Two
channels are used to convert from RS-232 to 0 to +5 VDC signals and two channels
are used to convert from 0 to +5 VDC signals to RS-232. This converter supports
TD, RD, RTS, and CTS. The DB9S female connector is for the RS-232 side. The
DB9P male connector is for the TTL/CMOS side. This unit is powered from the RS-
232 data and handshake lines whether the lines are high or low.
Pins used are:
DB9S Female DB9P Male
RS-232 TTL/CMOS
Pin Function Pin
3 (input) .............................TD .......................... 3 (output)
2 (output)...........................RD .......................... 2 (input)
7 (input) ............................RTS ......................... 7 (output)
8 (output)..........................CTS ......................... 8 (input)
Pin 5 is signal ground for both connectors. This unit is powered by the signals on pins 7(RTS), 4(DTR), and 3(TD).
These handshake lines can be in either the high or low condition, but must be present to power the converter. The unit can
work at baud rates up to 115.2 kbps.
It is important that TTL/CMOS logic, and only TTL/CMOS logic (0 to +5 VDC) is used for the TTL/CMOS side of
the converter. The maximum sinking current for one TTL/CMOS output is 3.2 mA. The maximum source current for one
TTL/CMOS is 1 mA. Signal levels are inverted by the converter. Please refer to table below.
Polarity
TTL/CMOS Input RS-232 Output
Low (< .8V) +5V minimum, +9V typical
High (> 2V) -5V minimum, -+9V typical
RS-232 Input TTL/CMOS Output
Low (< .2V) +3.45V minimum, +4.6V typical
High (> 2.4V) +.55V maximum, +.1V typical
© B&B Electronics -- Revised August 2001
This product designed and manufactured in USA of domestic and imported parts by
This datasheet has been downloaded from http://www.digchip.com at this page
Document No. 232LPTTL3201 - pg. 2/2
DECLARATION OF CONFORMITY
Manufacturer’s Name: B&B Electronics Manufacturing Company
Manufacturer’s Address: P.O. Box 1040
707 Dayton Road
Ottawa, IL 61350 USA
Model Numbers: 232LPTTL
Description: 4-Channel RS-232 to TTL/CMOS Converter
Type: Light industrial ITE equipment
Application of Council Directive: 89/336/EEC
Standards: EN 50082-1:1998
EN 61000 (-4-2, -4-3, -4-4, -4-6)
ENV 50204
Michael J. Fahrion, Director of Engineering
Specifications
Supply Voltage: Port Powered
Temperature Range: 0°C to 70°C
Data Rates: Up to 115.2 kbps
© B&B Electronics -- Revised August 2001
This product designed and manufactured in USA of domestic and imported parts by
