1794 - ispMACH 4000ZE: How does the Lattice ispMACH 4000ZE PICO Development Kit which uses the FT2232H for programming, connect TDO from the CPLD which is 1.8V (Vcc) to the FT2232H which is at 3.3V?
For systems that cannot interpret the TDO of the ispMACH 4000 Family, a voltage translator can be used to translate the TDO to 3.3V. One possible device to use in this situation is the 74LVC07A.
Lattice evaluation boards use 3.3V pull up on TDO to bring up the voltage level up to the desired voltage.This method is used to increase the cost effectiveness of the evaluation boards.
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