Double Magnet Coin Vibration Motors

Standard coin vibration motor (with brushes) are not noted for their fast rise and fall times and hence are not the best choice for haptic feedback applications. They incorporate a single magnet situated under the motors rotating voice coils / counter weight assembly, at the base of the coin motor. Our engineers recently discovered that by adding a second magnet above the voice coil / counter weight assembly, effectively sandwiching it between both magnets, many of the vibration motors performance characteristics dramatically improved.  Most notable is that this “Double Magnet”  design greatly improved the rise / fall times as well as the G force.  Power consumption is comparable to that of the single magnet design. 

As can be seen from the table above, the rise / fall times are better than that of an LRA and there is no need for an external driver IC.  They can be driven with DC voltage and do not require a driver IC.   Being a brush type motor, the over motor lifetime (100K cycles) is not as good as that of a coin LRA  (1000K cycles).

Pricing is slightly higher than that of a standard single magnet, brush type, coin vibration motor, but about 30% less than that of an LRA and even more so if you factor in the required driver IC for the LRA.

CLICK HERE to see photos of how coin motors have been mounted in products.