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- UID
- 104636
- 性别
- 男
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在LAYOUT PCB的时候，为了保证信号完整性，往往需要在输出端串联一个33欧左右的阻抗匹配电阻，CYCLONE II的手册上提到，其I0口已经内置了OCT匹配电阻
I/O Driver Impedance Matching (RS) & Series Termination (RS)
Cyclone II devices support driver impedance matching to the impedance
of the transmission line, typically 25 or 50 Ω . When used with the output
drivers, on-chip termination (OCT) sets the output driver impedance to
25 or 50 Ω by choosing the driver strength. Once matching impedance is
selected, driver current can not be changed. Table 10–7 provides a list of
output standards that support impedance matching. All I/O banks and
I/O pins support impedance matching and series termination. Dedicated
configuration pins and JTAG pins do not support impedance matching or
series termination.
手册上找到这段，不过还是不明白具体在QUARTUS当中要如何设置相应的管脚呢？ |
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