Hello, please let me know if this is a repost.
I would like to use a microcontroller running at 3v to send data to an LCD that runs at 5v. To do the level conversion I plan to use NPN transistors. The data should be sent at around 8mhz. I have looked at different transistors but the datasheets aren't exactly clear about what the maximum frequency the transistor can work at would be. I tried adding up the various rise and fall times for the 2N2222s I have and came out with about 2MHz as the max frequency. The logic levels for high and low of the LCD are listed as 0.8*Vdd and 0.2*Vdd, though, so the signal may not have to completely rise or fall to be valid.
Is there any straightforward way to calculate how fast I could send data by looking at a transistor's datasheet?
I would like to use a microcontroller running at 3v to send data to an LCD that runs at 5v. To do the level conversion I plan to use NPN transistors. The data should be sent at around 8mhz. I have looked at different transistors but the datasheets aren't exactly clear about what the maximum frequency the transistor can work at would be. I tried adding up the various rise and fall times for the 2N2222s I have and came out with about 2MHz as the max frequency. The logic levels for high and low of the LCD are listed as 0.8*Vdd and 0.2*Vdd, though, so the signal may not have to completely rise or fall to be valid.
Is there any straightforward way to calculate how fast I could send data by looking at a transistor's datasheet?
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