Linear Resonant Actuator (Also call it Linear Vibration Motor) is a very particular vibration motor compare to Eccentric Rotating Mass motor that provides not only faster response time and long lifetime but also stronger vibration. Due to its excellent performance, it has been more and more popular in the field of communication and wearable devices.
A linear Resonant Actuator is a spring + mass system. The mass moves linearly, up and down in the picture in the right, come into being the required haptic feedback. The linear Resonant Actuator must be driven at a narrow band(+-2 HZ) around the resonant frequency because of the spring constant. And different from a DC vibration motor, LRAs require an AC driving signal that can move the actuator up and down. If driven properly, they could be highly efficient and offer excellent acceleration.
Currently, Baolong focuses on 0832 type LRA. This LRA is also the most widely used linear motor at present. Imagine that a motor with only a diameter of 8mm and thickness of 3.2mm can bring more than 1G vibration. That’s why this motor is so popular now.
You can click on the picture below for the details of the motors. We detailed the specifications, pictures, datasheet and so on for each motor. If you have any question or can’t find a suitable motor you can contact our engineer freely. All your emails will be handled in 24 hours.
Our BLM0832-FP74-1S-U coin linear resonant actuator vibrates in the Z-Axis at 235 Hz. Rather than wire leads, it makes usage of a flexible printed circuit (FPC). PCB mounted pogo pins are suggested to get hold of the contacts pads on the FPC. Its current features make it a fantastic choice for wearable devices with limited electric battery capability. It draws only 19 ma @ 0.6 V while producing a vibration G-force of 0.55.
Our BLM0832-FP78-U coin linear resonant actuator vibrates in the Z-Axis at 235 Hz. Compare to BLM0832-FP74-1S-U; this motor has the same performance parameters but different FPC. We highly recommend you to use this motor in the phone or wearable devices.
In comparison with the typical Eccentric Rotating Mass motors, LRA’s are more expensive and must be drived by an AC signal. Of course, you can drive it by debugging PWM, but in order to achieve the best motor performance, we highly recommend that you use an external IC to drive it.Many companies make IC drivers for Linear Resonant Actuator supplying the right drive signals and include a library of haptic results you can choose. TI is definitely one particular company which makes LRA drivers IC. If you want to know more about TI IC, you can click on the link below.
The coil is powered by AC and remains stationary inside of the LRA. The Internal magnet has N/S polarity. Under the above conditions, the electrified coil generates the magnetic field to move the magnet to attract the repel so that that spring can drive the mass block up and down to generate force.