4 Con
fi
guring the Level Shifter
4.1 Selecting Shifting Level
There are two options for selecting the Target side logic level.
The
fi
rst method is to use the power supplied to the Level Shifter Board to power the
target device. In this method, the output voltage must be enabled by placing a jumper on
the
TPWR
pins. Then a second jumper is used on one of the voltage selection pins
illustrated in Figure 10. The pins are clearly labeled with the output voltage that they will
set. If no jumper is set on these pins, then it will default to 1.2 V.
Figure 10
: A jumper must be placed on the appropriately
labeled header for the desired voltage level. If supplying
power from the Level Shifter Board to the target, a jumper
needs to be place on TPWR as well.
The second method is to match the power supplied to the Target side when using a self-
powered device/board. When using this option, the logic levels will be set to match the
voltage levels applied to TPWR as shown in Figure 8.
In this con
fi
guration, the
TPWR
jumper must be removed. Simply connect the power and
ground of the target device to the power and ground of the Level Shifter Board Target
side. In order to function properly, the target's voltage level should not exceed 3.3 V.
Level Shifter Board User Manual v1.01
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