A linear resonant actuator is a motor used for production of an oscillating force across a single axis. A linear resonant actuator uses AC voltage to drive a voice coil pressed against a moving mass connected to a spring. When the voice coil is driven at the resonant frequency of the spring, the actuator vibrates with an observable force. Although the frequency and amplitude of a linear resonant actuator may be adjusted by changing the AC input, the actuator must be driven at its resonant frequency to generate a meaningful amount of force for a large current. Thus, it is used as a key component in haptics technology. The eccentric rotating mass (ERM) motor and linear resonant actuator (LRA) is two of the most common types of haptic actuators used in the market today. The haptics technology uses the sense of touch in devices to provide information to the user. This technology can be incorporated into products by using actuators or motors which generate vibration. Many routine devi...