Using a chip with two different power input requirements
The +5V supply voltage is not a high current demand and so it shouldn't be an EMI problem but if in doubt, a series resistor can be used of say 10 ohms followed by a suitable de-coupler at the pin such as 100nF. A 1uH inductor could even be put in series with the 10 ohm to further reduce any potential EMI problems.

Note that the +5V supply pin (\$V_{dd}\$) does have a maximum rating of 6V so consider using a 5.6V zener diode in parallel with the incoming 5V to prevent potential damage to the chip from inadvertently applying slightly higher voltages.