Two ultraflat dc motors are 15 and 26 mm in diameter and 5 to 7-mm long.
The 10,000-rpm motors achieve a constant torque of 3 mNm. The rotor revolves in an axially aligned neodymium magnetic field without cogging or iron loss. Precious-metal commutation creates low-transition resistances letting the motor operate with low starting voltages suitable for battery-operated portable devices.
MicroMo Electronics Inc., 14881 Evergreen Ave., Clearwater, FL 33762, (800) 807-9166, micromo.com