MAX3232 Mini RS232 To TTL Converter Module is a small, compact converter, to convert RS232 (+12V/-12V) to TTL (3V/5V) UART, which is based on MAX3232 chip. The MAX3222/MAX3232/MAX3237/MAX3241 series are low-power and high speed up to 1Mbps RS232 transceivers. The MAX3232 chip is a dual line of drivers and receivers, which is protected against ESD terminal to terminal connection (including GND). This chip just needs four 0.1µF external small capacitors, to charge-pump current, for reducing a required dual supply ±12V to a single from +3V to +5.5V voltage. The MAX3222, MAX3232, and MAX3241 certainly run at data rates of 120kbps while maintaining RS-232 output levels. The MAX3232  module is an RS-232 Transceivers Module with DB9 Female Connector, compliant with TIA/EIA-232-F standards and gives the designers an electrical interface between an asynchronous communication controller and the serial-port connector. It can work up to 250 signal rate with a maximum of 30-V/μs driver output slew rate.This module is a plug and play module, so does not need any driver. Its level can be changed from RS232 levels to TTL level easily, which makes software download and serial communication easy for an STC series microcontroller.
Features of SP3232 RS232 to TTL Serial Port Converter Module:
Chip Model: MAX3232CSE
Interface Type: RS232 To TTL
Voltage Range: 3V~5V
Maximum Baud Rate: 120kbps
interface RS232 : DB9 – female
interface TTL : 6pin
Support : Universal Asynchronous Data Receiver & Transmitter (UART) and (DTE) Data Transmission Equipment & (DCE) Data Communication Equipment
Size: 15.9mm x 9.4mm x 2.5mm
 
more info : https://circuitdigest.com/article/rs232-serial-communication-protocol-basics-specifications#:~:text=RS232%20is%20a%20standard%20protocol,data%20exchange%20between%20the%20devices.