Max232 TTL Converter IC
The MAX232 is an integrated circuit (IC), that converts signals from a TIA-232 (RS-232) serial port to signals suitable for use in TTL-compatible digital logic circuits. The MAX232 is a dual transmitter / dual receiver that typically is used to convert the RX, TX, CTS, RTS signals.
The drivers provide TIA-232 voltage level outputs (about ±7.5 volts) from a single 5-volt supply by on-chip charge pumps and external capacitors. This makes it useful for implementing TIA-232 in devices that otherwise do not need any other voltages.
The receivers reduce TIA-232 inputs, which may be as high as ±25 volts, to standard 5-volt TTL levels. These receivers have a typical threshold of 1.3 volts and a typical hysteresis of 0.5 volts.
The MAX232 replaced an older pair of chips MC1488 and MC1489 that performed a similar RS-232 translation. The MC1488 quad transmitter chip required 12 volts and – 12-volt power, and MC1489 quad receiver chip required 5-volt power. The main disadvantages of this older solution were the +/- 12-volt power requirement, only supported 5-volt digital logic, and two chips instead of one.
Max232 TTL Converter IC Features
- TTL/CMOS to RS232 Converter IC
- Can support two conversions at the same time (Dual drivers and Receivers)
- Easy to set-up and initialize
- Operating speed: 120kbit/s
- ±30-V Input Levels
- Operating current: 8mA
- Available in 16-pin PDIP, SO, SOIC packages
MAX232 Pin Configuration and Description
|Pin Number||Pin Name||Description|
|1||C1 +||Connects to the positive end of the First capacitor|
|2||V+||Connects to one end of the capacitor & another end is grounded|
|3||C1 –||Connects to the negative end of First Capacitor|
|4||C2+||Connects to positive end of the second capacitor|
|5||C2-||Connects to negative end of the second capacitor|
|6||V-||Connects to one end of the capacitor & other end is grounded|
|7||T2 OUT||Transmission pin of second converter module for RS232 cable|
|8||R2 IN||Reception pin of second converter module for RS232 cable|
|9||R2 OUT||Reception pin of second converter module for Microcontroller(Rx)|
|10||T2 IN||Transmission pin of second converter module for Microcontroller(Tx)|
|11||T1 IN||Transmission pin of first converter module for Microcontroller(Tx)|
|12||R1 OUT||Reception pin of first converter module for Microcontroller(Rx)|
|13||R1 IN||Reception pin of first converter module for RS232 cable|
|14||T1 OUT||Transmission pin of first converter module for RS232 cable|
|15||Ground||Connects to the ground of the circuit|
|16||Vcc||Connects to the supply voltage typically +5V|