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Do you know what an emitter-follower is? If not try Google.
I have tried both a transistor (1GHz) and a FET. Neither work. Use a SMD chip.
He doesn't need to mention his load. Even with a typical minimum circuit stray capacitance value, a common-emitter or common-source will not be able to drive it at 20MHz unless the collector/drain resistor is a low value.
What is the voltage swing of your input signal? What is the source of this signal?
Do you want a digital output, with 0V and 5V logic levels?
Let's see if we have this straight. The source is a 20MHz sine wave swinging 1.8 to 2.5V, and you want 0 to 5V out. Is that correct?yes is 0 to 5v
and i think i tried so many things i kinda give up i will pay $50 to anyone who can solve this problem
How long is the wire (or trace) from the microcontroller to the "other chips"? How many other chips are connected, and what are they?
You can't do that at 20MHz, due to transmission line effects. A transistor is not going to sove your problem. Are you trying to daisy chain them, or do you have a separate line from the µcontroller output to each STP24D05?The Microcontroller is a PIC32 and the slave are STP24DP05
the I'm trying to connect 8 STP24D05 about 6 inches apart from eachother, so the last chip is 4 feet away from the microcontroller.
You can't do that at 20MHz, due to transmission line effects. A transistor is not going to sove your problem. Are you trying to daisy chain them, or do you have a separate line from the µcontroller output to each STP24D05?
I couldn't find STP24D05 with Google. Can you provide a link to the datasheet?
What voltage are you using for Vdd on the STP24DP05? (You left out the P, which is why I couldn't find the datasheet).
You didn't answer all my previous questions.
You may have problems with any clock frequency. The long transmission line will have reflections. The problem is with the clock rise and fall times, not the frequency per se.I use 5V to drive the STP24DP05 , yes sorry I miss that part yes I'm daisy chain them there a single SPI bus line that runs 4 feet and each STP24DP05 feeds from that line.
What I will try to do is slow down the clock and see if it works that way, I will do it tomorrow I been playing with this since I got up this morning.
I use 5V to drive the STP24DP05 , yes sorry I miss that part yes I'm daisy chain them there a single SPI bus line that runs 4 feet and each STP24DP05 feeds from that line.
What I will try to do is slow down the clock and see if it works that way, I will do it tomorrow I been playing with this since I got up this morning.
Some people learn about transmission lines in the school of hard knocks.4 feet? and you were wondering why it was not working? you need special drivers and wires for RF at those distances
Some people learn about transmission lines in the school of hard knocks.![]()
indeed ... all the while causing the rest of us to get hard knocks as our heads hit the walls!