03-13-2011 04:07 AM
Hello,I've designed a circuit to generate step and directoin signals for external stepper motor drivers. The input current for these drviers is "-1 mA" which I believe means I need to sink 1mA of current. Is the FPGA capable of sinking this much current? I have read that it can output up to 24mA but how much can it sink? I did not find this information anywhere. If anyone can help me I would really appreciate it! My board is a DE2-115 and the output pins are of the GPIO pins using 3.3 volt logic.
03-13-2011 07:51 AM
--- Quote Start --- Is the FPGA capable of sinking this much current? --- Quote End --- Yes, the output characteristic of FPGA and CPLD I/Os is almost symmetrical. The sink capabilty will be even slightly higher than the source strength. Some numbers can e found in the DC characteristic part of the device data sheet, complete data for individual IO standards and current strength settings can be found in the ibis files.