Model 232LPTTL converts RS-232 to 5VDC TTL/CMOS compatible levels. Model 232LPTTL33 converts RS-232 to 3.3VDC TTL/CMOS compatible levels. Two channels are used to convert from RS-232 to TTL/CMOS signals and two channels are used to convert from TTL/CMOS signals to RS-232. These converters support TD, RD, RTS, and CTS. DB9S female connector on the RS-232 side. DB9P male connector on the TTL/CMOS side. This unit is powered from the RS-232 data and handshake lines, whether the lines are high or low.
Pin 5 is signal ground for both connectors. Both models are 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 for the 232LPTTL, and 0 to +3.3VDC for the 232LPTTL33) 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 converters. Please refer to table below.
