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Altera_Forum
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14 years ago

Clock Voltage on Max7000

Hi there! I'm doing a PCB design which includes a microcontroller and a MAX7000 CPLD. As the controller's IOs work on 3.3V we decided to run the MAX7000's IOs also on 3.3V. The core is using 5V...
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Altera_Forum
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14 years ago

If you read the MAX7000 data sheet thoroughly, you'll notice:

- Input buffers are supplied from VCCINT and thus independent of VCCIO.

- MAX7000 inputs have a TTL level specification, minimal high level is 2.0 V. 3.3V CMOS and 5V CMOS/TTL levels are fine to drive the inputs, including clock.