HiLetgo 10pcs Mini RS232 to TTL MAX3232 to TTL Level Converter Board Serial Converter Board RS232 to TTL Serial

Works fine. I was a little leery after reading some reviews, but read enough of them to avoid the potential issues. I'm using it to add 2 serial ports to a Raspberry Pi.Things to keep in mind:1) There are TWO converters, one on each face of the board. There's not enough room on the chip side to label which end is TTL and which is RS232 (did I mention it's tiny?), but it matches the other side which is clearly labeled.2) If you're not using the second converter, don't leave the input floating or it'll overheat. See other reviews for how to add a pullup resistor.3) I had no trouble attaching flexible 28 gauge wire to the small solder pads. I could see if you tried attaching larger or solid wire, or a component directly, it could be dicey.4) Some reviewers complained about mounting it, but it's easy if you attach all 8 wires first. Then connect power using the through-holes (I snipped leads from diodes for this), so the whole thing is suspended over your main PCB. I added a 3rd lead to the other side to secure it better.So don't let the other reviews scare you. It works, and good luck finding anything more compact or cheaper.

Way too much power draw on every one. They get so hot they’ll give you a burn. On each board the + pads are common as are the - pads and none of the pins are shorted.These are so difficult to work with I wouldn’t rate the very well even if they worked.

If you are payed 20$ an hour and time is money save yourself 100$ by buying something else. The chip works (that is the reason for the second star) but to use it I had to spend 5 hours soldering.The data pins do not have holes and if you solder anything to the metal straps they come off at the slightest pressure. And I do not mean that what you have soldered comes off. The metal strip from the board comes off making the board unusable.Finally I came up with a design that holds and works..The other think is how much power those chips take. When I connect it it dims the lid and they become pretty hot. I doubt they can be used for a project that runs 24 hours....In other words save yourself some time, keep your blood pressure down and buy something else.

Some of these overheat. The problem is that they use a substitute MAX3232 chip that is missing an internal pull up on pins 9 and 10. Only half this chip is used on this board and pin 10 is not connected and floating. The result is that the chip can oscillate at a high frequency and overheat. The solution is to add a pull up resistor to V+ on pins 9 and 10. Any value from 20K to 400K will work. As only 1/2 the chip is used you can connect 9 and 10 together and that makes adding the resistor much easier. After the added resistor the boards seem to work fine.

These work well and do not heat up, however, there is a key point that the seller needs to emphasize - these devices provide *two* RS232 (TX, RX) pairs. Each pair is on one side of the PCB - this is the reason for the pads without holes. The other users that talk about drilling through those pads are shorting two different channels and make the channel drivers fight each other, resulting in higher heat dissipation.Note to seller - personally, I would have preferred if the TX/RX pairs used four through-hole pads on each side and the connections to GND and Vcc were on the bottom as pads you solder to. Or, even better, one can extend the PCB by 2.54mm and have two more through-hole pads.

Burned one up due to incorrect pinout - **NOTE** The previous review that posted an image of the board with pinouts labeled is *INCORRECT*. I used a VOM to verify the pinouts by finding the actual chip schematic and tracing the chip leads to the board pinouts, and I fixed the pinout image, attached here.As others have noted, the data solder pads are very touchy. I bought some 28-gauge silicone sleeve wire so as to not put tension and successfully built a little project using the Adafruit Breakout GPS and successfully connected to a computer RS-232 USB adapter and was able to receive and send NMEA sentences so it is definitely working as designed. I did use the 3.3v feed from the GPS board, and the MAX3232 chip does not get hot as all.

It can be a little frustrating because the power pins are through-hole and common, but the signals are not. I beeped it out and came up with this diagram. Connect the RS-232 LEVELS side to the RS-232 devices, connect the LOGIC LEVELS signals to your Arduino, Raspberry PI, ESP32 or ESP8266, or whatever. VCC can be either +5V _OR_ +3.3V, so match the input levels you are using (+5V for most Arduino, and 3.3V for everything else). You only have to connect power on one end of the board....they run through. So it is two logic level inputs (DIN1 & DIN2) driving two RS-232 outputs (DOUT1 & DOUT2), and two RS-232 inputs (RIN1 & RIN2) driving two logic level outputs (ROUT1 & ROUT2). Make sure you get your signal flow correct, i.e. don't have both sides trying to 'talk' on the same line.

Even assuming all these MAX3232 chips work fine,and there’s no reason to doubt it,The board design makes them practically unusablein any project I can imagine.These “breakout” boards are barely larger than the MAX3232 itself.Certainly, no provision for mounting, save perhaps hot glue.The solder pads are separate on both sides and *not* thru-hole.Even if you only need one channel,you’ll have to tack tiny wires to tiny pads on both sides.I can’t imagine why these were designed this way,as they’re certainly prototype (and even production) unfriendly.Like myself, you may have been looking for a MAX232 breakoutbut did not need a DB9 connector, and was seduced by the price.Frankly, you’d be better off buying one of those and desolderingthe DB9.Designing an ever-slightly larger, breadboard/prototype-friendlypanelized PCB is a trivial task. I cannot imagine why they choseotherwise.Sadly, I must return these.

a little fiderly to conect up, work well have used several.