I am converting an output signal from JA-01 on a Cerebot MX3cK every 300ns. I use a PmodLVLSHFT to convert the 3.3V output signal to a 5V signal for interfacing some LEDs with very strict timing. The PmodLVLSHFT responds very quickly to a change on pin JA-01, but overshoots/undershoots (oscillates) for about the first 50ns after the signal has transitioned. I have tried using a small capacitor to smooth the rise/fall, but all attempts result in either too slow of a rise/fall time or no change at all. Do you have any other suggestions on how to eliminate the overshoot/undershoot and preserve the quick rise/fall time of the signal?
It should be noted that the overshoot/undershoot is present on the 5V output signal of the PmodLVLSHFT when there is no load attached to it, i.e. no LEDs. Also, the signal is not used as the power source for the LEDs, it is merely a digital input signal for writing 1's and 0's into shift registers. The PmodLVLSHFT is brand new, thus it has not been used for any other project. I measure the overshoot/undershoot by hooking the output of the PmodLVLSHFT up to a 100MHz oscilloscope directly.
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Josh Sackos
Hi Guys,
I am converting an output signal from JA-01 on a Cerebot MX3cK every 300ns. I use a PmodLVLSHFT to convert the 3.3V output signal to a 5V signal for interfacing some LEDs with very strict timing. The PmodLVLSHFT responds very quickly to a change on pin JA-01, but overshoots/undershoots (oscillates) for about the first 50ns after the signal has transitioned. I have tried using a small capacitor to smooth the rise/fall, but all attempts result in either too slow of a rise/fall time or no change at all. Do you have any other suggestions on how to eliminate the overshoot/undershoot and preserve the quick rise/fall time of the signal?
It should be noted that the overshoot/undershoot is present on the 5V output signal of the PmodLVLSHFT when there is no load attached to it, i.e. no LEDs. Also, the signal is not used as the power source for the LEDs, it is merely a digital input signal for writing 1's and 0's into shift registers. The PmodLVLSHFT is brand new, thus it has not been used for any other project. I measure the overshoot/undershoot by hooking the output of the PmodLVLSHFT up to a 100MHz oscilloscope directly.
Thanks,
Josh
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