Running servos and microcontrollers off the same battery.

[Hawaii00000]

Is it true that running servos and microcontrollers off the same battery causes interference?

[jka]

Yes. Servos, like any other motors, generate "electric noise". You can remove some of this noise by using capacitors on your power supply lines around the ICs in your circuit. Mount a 0.1uF capacitor between +5V and GND as close to each IC as possible and maybe a larger capacitor near the voltage regulator.