Can I replace SP232AEP with MAX232?

[tbj]

Hi,

Assembled my MS2-V3.0 board today. Everything went smoothly apart from putting in the SP232 UART chip in backwards. Rather than risk damaging the board by sucking it out I decided to cut the pins off. Now I need another UART.

The one that came with the (DIYAutoTune) kit was an SP232. Can I replace this with a MAX232 which are cheaply available at my local supplier? Does it matter what variant? I have a CPE+, NG4, N and IN variant to choose from.

Cheers!

[Matt Cramer]

We cross shop a couple of brands to get the best deal on parts for our kits; the main difference is the SP232AEP is made by Exar and the MAX232 by Maxim or Texas Instruments. The variations you mention decode to:

CPE+ = Maxim, 0 to 70 degrees C
NG4 = TI, 0 to 70 degrees C
N = TI, -40 to 85 degrees C - this is the one you want.
IN = TI, 0 to 70 degrees C

[tbj]

Thanks Matt.

Looking at the datasheet it appears the MAX232N requires 1.0uF charge pump caps instead of 0.1uF ones, and it looks like the ones in the schematic are 0.1uF. I take it I should replace these as well?

Cheers.

[Matt Cramer]

The MAX232A variants can use 0.1 uF's.

[tbj]

Found a MAX232ACPE+. Rated -40 to +85C. That should do it, I think. Cheers for the help

[Six_Shooter]

I've used MAX232's with .1uF caps without issue for a few different applications (not MS related), but the functionality is the same.

[tbj]

Thanks all. I've been able to load the firmware onto the board and can connect to it with Tunerstudio, so I guess it's working