Coin Linear Vibration Motors (LRA’s)
|We manufacture both rectangular and coin type LRA’s. This section only discusses coin type LRA’s.
Due to their fast rise and fall times and superior braking ability, linear resonant actuators (LRA) vibration motors are an excellent choice for haptic feedback applications. Their relatively simple internal construction also offers high reliability and exceptionally long life when compared with brushed ERM motors. Our coin shaped linear resonant actuators oscillate along the Z axis, perpendicular to the motors surface. This Z axis vibration efficiently transmits vibrations in wearable applications. In Hi-Rel applications, they are a viable alternative to brushless vibration motors as the only internal parts that are subjected to wear / failure are the springs.
|Config. Type||Motor Size||Voltage||Current||Response Time
- 50% of power
- Maximum values
|Vibe Force (G)|
|Dia (mm)||Thickness (mm)||Rated (VDC)||Operating (VDC)||Rated (ma) MAX||Typical* (ma) Avg.||Rise Time (ms)||Fall Time (ms)|
|The “typical current” is the average current from 20 motors selected at random from a given production lot. Copies of the test report showing the data collected for all 20 motors are available upon request.|
- Custom wire length are available for MOQ: 1K pcs
- We can add connectors for MOQ: 1K pcs
- Custom FPC’s are available for MOQ: 6K pcs.
- Tooling and design fees will apply for custom FPC’s
When compared to standard brushed ERM vibration motors, LRA’s are higher in price and must be used with external driver IC.
Unlike conventional brushed DC vibration motors, linear resonant actuators must be driven by an AC signal at the devices resonant frequency. The wire leads are typically different colors BUT the wires do not have polarity as the drive signal is AC , not DC. A number of companies make IC drivers for linear vibration motors that supply the correct drive signals and contain a library of haptic effects you can choose from. TI is one such company that makes LRA drivers IC’s. TI makes and evaluation board that incorporates the TI DRV2605L haptic driver IC. See below link for info:
It should be noted that unlike brushed ERM vibration motors, varying the amplitude of the applied voltage will only change the amplitude of the vibration force, not the frequency of vibration. Due the LRA’s Hi-Q , applying a frequency above or below the resonant frequency of the LRA will result in the LRA producing a lower vibration amplitude or if far from the resonant frequency, none at all.