Conversion between the 3.3v to 5v logic signal.
.from: http://www.edaboard.com/thread11539.html
Hot to do an 5V signal will be level-shift to 3.3V and the 3.3V signal will pass-thru directly without attentuation.
Solution 1:
My simple method is to use serial resistor divider (few kilos, ie. 10kR) and diode (Schottky diode) to +3.3V (A - resistor, K - +3.3V).
Solution 2:
look 74LVC series chips, that's also available in very small one gate package ( and it is very low cost, for example the Philips 74LVC1G125GW or Texas Instruments SN74LVC1G125DCKR chips in small 5 pim SC-70-5 packege, low unit cost
Solution 3:
Take a look at www.chipcon.com in Application Note AN021. Texas Instruments has a similar good PDF appnote also.
