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Altera_Forum's avatar
Altera_Forum
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16 years ago

SRAM 160MHz, impedance matching

Hello, In my board I have one SRAM directly connected to a FPGA Cyclone 2. I am working at 160MHz. But sometimes I have an strange behavior when reading the SRAM. I am sure is something ab...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Hello,

I changed the pin assignement to "minimum current strenght" but in the output there are more noise.

Why I can not use the termination 50 Ohms series resistance?, when I try to use it I have this error:

Error: I/O standard 3.3-V LVTTL on output I/O pin D0_bus_B cannot have Termination logic option setting Series 50 Ohm.

I still have problems with the Impedance matching, and I can not check the actual signal waveforms at the load with a low capacitance probe. In my board there is no way to connect an osciloscope.

Bye and thanks.