Datasheet

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Figure 4 - GPSI 32 DUT to SPIO4 Mating
2.5.1 Level Shifters
The board incorporates level shifters to allow flexible output voltages on the uni-directional SPI signals of
GPSI-16 port, as shown in the board block diagram. VDDIO – a supply voltage from the GPSI-16/32
connector coming from the DUT board – provides the voltage to the output side of the level translators. If
the DUT has no special requirements for voltage and simply needs basic 3.3V signal levels, the 3.3V
output from the GPSI connector could be connected to VDDIO on the DUT board. The level shifters are
uni-directional. If VDDIO is not provided, the level shifters enter a shutdown state with all input pins tri-
stated. The state passed along to the processor in this case would be logic low.