MAX232 dual EIA 232 drivers and receiver line bus driver IC

The MAX232 IC is used to convert the TTL/CMOS logic levels to RS232 logic levels during serial communication of microcontrollers with PC. The MAX232 is a dual driver/receiver and typically converts the RX, TX, CTS and RTS signals. The drivers provide RS-232 voltage level outputs (approx. ± 7.5 V) from a single + 5 V supply via on-chip charge pumps and external capacitors. This makes it useful for implementing RS-232 in devices that otherwise do not need any voltages outside the 0 V to + 5 V range, as power supply design does not need to be made more complicated just for driving the RS-232 in this case. The receivers reduce RS-232 inputs (which may be as high as ± 25 V), to standard 5 V TTL levels. These receivers have a typical threshold of 1.3 V, and a typical hysteresis of 0.5 V. The later MAX232A is backwards compatible with the original MAX232 but may operate at higher baud rates and can use smaller external capacitors – 0.1 μF in place of the 1.0 μF capacitors used with the original device.

Images/Pinout of MAX232 Dual EIA-232 Drivers & Receiver

Features of MAX232 Dual EIA-232 Drivers & Receiver:

• Meets or Exceeds TIA/EIA-232-F and ITU Recommendation V.28.
• Operates From a Single 5-V Power Supply With 1.0-µF Charge-Pump Capacitors.
• Operates up to 120 kbit/s.
• Two Drivers and Two Receivers.
• ±30-V Input Levels.
• Low Supply Current: 8 mA.

Applications of MAX232 Dual EIA-232 Drivers & Receiver:

• Battery-Powered Systems requiring UART communication with COM port of older PC.
• Connection of Modems to microcontrollers.
• DIY projects for connecting to a COM port of a computer and various other components such as GSM module etc.