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Posted Jan 11, 2012 at 11:56 am
Figure 1
This is a small portable RS232 – TTL converter circuit that is based on one of the most common ICs MAX232. The minimum number of components are used to operate MAX232. Additionally a +5V voltage regulator 7805 and two supply capacitors are used. If you want to bypass the regulator components 7805, C1 and C2 short the pins 1 and 3.
Source: http://users.picbasic.org/Howto/TTL-RS232/ttl.htm
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2 years ago: thanks for this circuit, it's just a matter of proper soldering to the pins of RS232 to make it work properly since there are only a few components used to build this!
2 years ago: what could be the equivalent IC for MAX232? even if not exactly the same?
2 years ago: This is a very popular converter. I always see them in many computer interfaced circuits. Maybe it's time to build my own like this! thanks very much!
1 year ago: Hi, guys : i have a PDA windowsCE equipment that supply RS232 +-12V (I need only rx and tx and GND) , and I want to communicate with a peripheral that accept to communicate only in UART TTL !
1/ So can I use the max 232, even if i have no +5V power ?
2/ i yes : in this case do you confirm I have just to short the pin 1 and 3 ?
3/ what about the other pins : C4 , C5, C6 do I need the capacitors ? and if not just is to short them ?
sorry i don't understand very well the max232 document, too complicated for me, thanks a lot to adsvise how i can make it work easy.