Electrical Engineering Stack Exchange
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Questions tagged [max232]

Anything related to the MAX232 integrated circuit. The MAX232 IC is used to convert serial communication signals using TTL levels, such as those produced by UARTs ICs, from and to standard RS-232 line signals.

Anything related to the MAX232 integrated circuit. The MAX232 IC, described in its datasheet as a dual EIA-232 driver/receiver, is used to convert serial communication signals using TTL levels, such as those produced by UARTs ICs, to standard RS-232 line signals.

See also Wikipedia on MAX232 IC and Texas Instruments MAX232 datasheet.

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How does the MAX232 double the voltage?

MAX232 Datasheet Hi, I am currently a student so bear with me please! I'm currently using a powering the MAX232 with 5V DC, and when I measure from VCC to lets say, pin 3, I am getting a voltage reading of around 13V on my voltmeter. Using a power…
Phibz
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Capacitors in MAX 232

Out of curiosity, can I replace the electrolytic capacitors in the circuit with non-polar ceramic capacitors? Will I get the shifting in level? MAX232 datasheet: LINK
Vaibhav Gursale
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Problems with homemade RS232-to-TTL converter board based on TI's MAX232

I've designed an RS232-to-TTL converter board based on TI's MAX232 IC that I plan to use to program a few custom Arduino boards that I have. However, I'm having trouble with the board and I'm hoping that someone can help me debug it. First, let me…
Ricardo
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Why MAX232 works without any capacitors?

I was playing today with a very simple setup of pic16f876 and max232 connected to the COM port of a PC running a terminal emulator. I was just testing (the uc simply echoes anything it receives) when I decided to try using smaller capacitors for…
Cleric
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Can I use 10\$\mu\$F caps in a MAX232?

this is just a quick and dirty question. I don't understand the purpose of the 1 \$\mu\$F caps in the MAX232 circuit. What do they do, exactly? Can they be skipped? Can they be swapped with 10 \$\mu\$F caps?
Rick_2047
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Do I have to use a MAX232 chip?

I am trying to interface my ATmega chips to the computer using a serial interface. I have read that this can be done directly by connecting the appropriate pin between the chips and the serial pin. But it is advised that I use a MAX232 chip. What is…
Rick_2047
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How to connect RS232 ("Opto-RS232")

--Background-- I'm setting up a pretty standard RS232 interface from a digital caliper to a microcontroller, via a MAX232 chip (or in my case, MAX3222, which is the 3.3V-supply variant with 2 transmitter pairs and 2 receiver pairs). The only thing…
boardbite
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MAX232 IC does not convert to and form RS232 levels

I made a simple circuit to read data from RS232 lines and print data on different RS232 lines. This is the IC I am using: MAX3232EIDWG4. The IC fails to convert the CMOS to RS232 level logic. I am suspecting it is because of a broken IC or because…
dreamcoder
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Interfacing a PIC microcontroller to different logic levels

I'm planning on interfacing a PIC microcontroller to two devices which operate on two different logic levels and I'm wondering what the best way of approaching this is. I'm rather inexperienced in this area and was hoping to get some ideas on the…
user1242670
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Can a MAX232 IC be used for RS-232C standard?

I have a GT01 Panasonic LCD which it's interface is RS-232C. I have read that the difference between RS-232 and RS-232C is their voltage level which it's ±5 V in RS232C. Can I use a MAX232 IC to communicate with this LCD? I'm worried that MAX232'c…
Amin
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Does Vs+ and Vs- need to be connected on a TRS232E?

I have a TRS232 RS-232 Driver(max232 equivalent). On the data sheet, it shows a capacitor on Vs+ and Vs- (1uF)and they just have arrows saying they go somewhere. Can I omit these connections and capacitors and if I do what are the side effects or…
jsolarski
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RS-232 Crossover, and Protection against shorting two TXD lines

I'm in the process of designing a USB to RS-232 converter for communication with some existing boards, and I ran into two problems. First Question I need a way to programmatically reverse the TXD and RXD lines, as there are some boards that are…
David Refoua
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MAX232 circuit not working

I am designing a circuit using a MAX232. I have connected Tx and Rx of the MCU to the 11th & 12th pin and connected the 14th & 13th pin to the RS232 cable. I do not have a UART port in my laptop, so I have used a UART to USB Cable. However, I am not…
S Andrew
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RX/TX LED for MAX232

I want to use two LEDs to show send and receive on my max232 RS232 to TTL (5v) converter. I have seen this method as the most conventional way to power an LED for max232: I tested it and the LED light was very dim and decreasing the resistor value…
arudino.tyro
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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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