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Author Topic: TTL to LVTTL  (Read 1916 times)
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Hi,
   I have a LVTTL GPS device(Rx & Tx lines) I am trying to convert the TTL from the arduino into LVTTL. Do I need to? Can I plug these straight into each other?
   The only place I can find a part to do it is Farnell, and they have a minimum order of £20 and a £15 P&P charge... The actual part is 7p!!!

Do i need to bother? or will I blow my GPS?
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St. Leonards-on-Sea, E. Sussex, UK.
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What GPS is it?

What is the Farnell order code? I'm just about to place an order with Farnell UK and I could add it, then post it on. I don't pay for shipping.
« Last Edit: May 06, 2010, 09:33:57 am by leon_heller » Logged

Leon Heller
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1631692. if you could grab me 10 it should be 67p. your a legend man!
the module is a LS-40EB-5V. (I'm hoping to stick it all in a high altitude balloon when i'm done!) smiley-grin
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To drop 5V signals to 3.3 use a resistive divider with something like 1k between devices and 2k2 to ground at the low voltage side.  Don't connect directly, that could easily blow something.

To boost 3.3V signals up to the Arduino, you probably don't need to, the thresholds are OK if the GPS puts out rail-to-rail logic (CMOS) levels.
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I've seen MOSFETs used for level conversion, I suppose that is the same sort of idea. I've ordered some for myself, as well. They might come in useful.
« Last Edit: May 06, 2010, 03:02:00 pm by leon_heller » Logged

Leon Heller
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Hello,

What can you say about Skylab SKM53 module
ttp://www.skylab.com.cn/datashe...Nav_SKM53_DS.pdf
?

Thanks for help. Needed very much.
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