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Altera_Forum
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15 years ago

VCCIO EPM7128SLC84-15 and 5 Volt outputs: HELP!

I'm using a MAX EPM7128SLC84-15 and need 5V logic outputs. So, the CPLD is wired with all VCC=5V and all the VCCIO = 5V too. Yet the outputs show 3.3V on the 'scope. I believed the Data Sheet page...
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Altera_Forum
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15 years ago

According to the MAX7000 datasheet (chapter MultiVolt-I/O Interface), external pull-up resistors are required to guarantee 5V CMOS compatible output levels. Without it, a Voh of about 3,8V is achieved with 5V VCCIO.