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Altera_Forum
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18 years ago

Help: HSMC and I2C

I am having a hell of a time trying to interface a camera through an HSMC - Santa Cruz adapter board (THDB-H2S - http://www.terasic.com.tw/cgi-bin/page/archive.pl?language=english&categoryno=39&no=21...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
18 years ago

Weak pull-ups are definitely too weak for regular I2C speed at some load capacitance. They can't be set to a higher strength. You should use external resistors of 1K to 4.7K maximum. As said, for SCL a push-pull driver can be used instead for most I2C applications, so basically an approriate SDA pull-up is what you need urgently.