Electrical Engineering Stack Exchange
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Questions tagged [max3232]

3V to 5.5V multichannel RS-232 line driver/receiver

The MAX3232 device consists of two line drivers, two line receivers, and a dual charge-pump circuit with ±15-kV ESD protection pin to pin (serial-port connection pins, including GND). The device meets the requirements of TIA/EIA-232-F and provides the electrical interface between an asynchronous communication controller and the serial-port connector. The charge pump and four small external capacitors allow operation from a single 3-V to 5.5-V supply. The devices operate at data signaling rates up to 250 kbit/s and a maximum of 30-V/µs driver output slew rate.

Refer to Texas Instruments website for more information.

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Crosstalk from RX to TX line on the RS-232 side of MAX3232C

We have a product which is using a MAX3232C for interfacing to a PC. Its RS-232 RX line is tied to the MAX3232's R1IN pin and its TX line to T1OUT: The problem we are having appears to be some kind of crosstalk between the RX and TX lines. This…
Claudio
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Why does the MAX3232 have two inputs and two outputs?

I am trying to make a PCB for TTL to RS232 converter. I am using the MAX3232. It looks 10-11, 14-7, 13-8 and 12-9 are the same. I see some diagrams where people only use one of them. For example,in this diagram: What should I do? Connect both or…
mehmet
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MAX3232 overheating/burnt after connecting to PC

I've got a MAX3232 Serial-to-TTL RS232 board which I am currently using in factory assembly lines. I don't have its picture, but here's a similar product: This is the circuit I've managed to figure out of the board(I don't have the original…
Sodrohu
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Can I connect two microcontrollers via RS232 separated by a distance of 3.5 inches? Both are on two separate PCBs

This design has two PCBs, each with a microcontroller. One can be said to be main and the other is a possible expansion if the user wishes to use it. The microcontrollers will communicate via RS232 (RX, TX, CTS and RTS lines.) Both boards will be…
Fabián Romo
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UART is garbled when running at more than 9600 bps

I'm connecting 2 MSP430F5529-based boards (running at 1 MHz) using UART and MAX3232 (MSP430F5529 -> MAX3232 -> cable, a few cm long - will be longer in our final application -> MAX3232 -> MSP430F5529). It works as long as the bit rate of the UART is…
Renan
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Weird output from MAX3232

Hi - I'm getting unexpected output from a MAX3232 board. I'm trying to reimplement a baseball scoreboard controller. The signal I'm trying to recreate is at RS232 levels (-5 to 5V) but uses a different encoding. I've got a Raspberry Pi Zero…
evm
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RS232 using a MAX3232 chip problems

I am trying to use RS232 to TTL convertor much like this: https://www.amazon.com/MAX3232-Female-Serial-Converter-Module/dp/B00BXX2OU2 I am not sure if the chip is authentic MAXIM or some knock off. When I connect the convertor to the rs232 device…
Greg S
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Atmega 328 uart program: compiler error on undeclared variable on register name ending with "n"

I'm trying to get the atmega328 to communicate over serial port with my pc. I'm using hyperterminal to echo back the keyboard character entries. I'm using the max3232 chip to do the communicated with the computer. When I try to compile it gives and…
Cjueden
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RS-232 Zero (-7V) drops when I connect db9 connectors

I'm interfacing with a system using RS-232. To communicate, I use MAX2322 for TTL <-> RS-232 to interface with PIC microcontroller and PL2303 for USB <-> RS-232 to interface with PC. All of the converters I've used, when not connected to the…
rnunes
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MAX3232: change output to be positive only

I have an existing product with a spare RS232 port on the rear panel. This is connected in the standard way to a MAX3232. I would like to use this to connect to another device that is TTL level, so I don't want the output to go below GND. The high…
StephenC
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RS422 and RS485; full-duplex or half-duplex?

I have extensively used RS232 transceivers in many projects and have fairly good understanding of UART communication using RS232 transceivers. MAX232 and MAX3232. Now I have to build my understanding about RS422 and RS485 transceivers. So far I…
alt-rose
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Generating dual rail power from a MAX3232?

I've seen several electronics devices using MAX3232 or similar devices to generate dual rail power supplies. In my instance, I have 3.3V going in and need regulated ±5V outputs. I have three four questions. How much output current can they sink or…
Thomas O
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MAX3232: Switch between RS-232 and TTL levels

Sorry in advance, electronics noob here! I need to make a proof of concept to get some data out of third party system which handles both RS232 and TTL levels. The computer/raspberry/arduino shall - I quote - be capable of receiving data via RS-232…
Laurent
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Maxim MAX3232 chip used as an interface with itself?

I am trying to use a MAX3232ECPE chip to communicate between two ESP32 Feather boards, just as practice with RS-232 conversion before I move on to communicating with an actual RS-232 device. (This is mainly because the device in question is often…
InBedded16
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Control power supply to MAX3232 IC using Arduino

Need to control the supply to MAX3232 ( RS232_TO_TTL) IC using Arduino. The 3.3V supply is also tapped from the Arduino board. I have to keep the Vcc supply of MAX3232 around 3V. With the present circuit diagram, the voltage drop is around ( hence…
seccpur
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