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I am trying to communicate between FPGA board to some interfaces kits like 12bit ADC, DUAL DAC, Stepper motor ...etc, FPGA out put voltage 3.3V only but for this interface kits needs 5V, so for this i need to use level shifters.
In order to convert 3v to 5v you can use any of the 74HCT series chips with 5v supply.
To convert 5v to 3v you can use the 74AHC series or 74LVC series (like 74AHC245) with a 3v power supply.
The AHC series can tolerate an input of 5v with a power supply of 3.3v so it can take 5v as input and output 3.3v
For digital you can use open collector transistor with pullup resistors. But for analog it is advisable to use OPAMP with known gain. If you are not... you will loose your voltage accuracy.
For example you need OPAMP amplifier with gain of 1.5 to get 3.3V input - 5v output (make sure you are using rail-rail OPAMP) ...
Do yo need digital interface or analog interface, then only i can give you clear explanation or circuit diagram... and how many port pin you need?
You need to use simple voltage level translator with one side 3.3v and the other side 5v,
the only thing that you need to be careful is about the direction of the signals whether they are all unidirectional or bidirectional based on that you need to select a voltage level translator, to be on safer side use a bidirectional voltage level translator.
below is the list of voltage level translators available from Texas Instruments.
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