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i also need this but with 3 to 8 MHz switching speed, what to use.
op-amp, high speed transistors or what?
i want buffer output not inverting. (3.....5 TO 15) and 0 to 0.
i also used ULN but that does not work with high speed also that inverts and if i use two propagation delay comes.
what to do?
If you do not have to drive huge loads you could use open collector buffers like 7406, 7416 (inverting) or 7407, 7417 (non inverting) they are both able to switch max 30V.
The only problem is that they can not deliver a strong H level (open collector).
Switching speed (and also power consumption) depends on the type of load and also on the size of the used pullup at the "high voltage" side.
A simple interface is a small FET with pullup resistor.
Connect the base to 3.3V, the source to your microcontroller and the drain with the pullup resistor to your CMOS load for a non-inverting solution. Philips has this solution in their I2C user guide
Otherwise TI has CD40109 or CD4504 for level translation, but they have CMOS levels on the inputs
Search site of Texas instruments. There you can find various chips that are used especially for bus voltage shifting. Take a look at CBTLV series and other "Cross Bar" chips. You can also find transceivers that has two voltage source inputs (for low voltage side and high voltage side).
Yes jzo777n, you are right! Sorry for wrong information.
Than i think that easiest way is to use sort of "Open Collector" system, and if you need more current use buffer after. To avoid any kind of noise it is best to use Schmitt Buffer after the Open Collector driver powered on 15V.
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