Sanyo DC Motor Division (Bensenville, IL) offers the PM Series brushless micro motor that incorporates a ceramic air bearing design, using air as a lubricant to solve problems encountered with typical motors lubricated with oil. The motors are available in a 20-mm size and are designed for applications requiring high speed and quiet operation at high temperatures. The sleeve and shaft of the ceramic air bearings contain a 3- to 5-micron gap between them. At the top of the shaft, magnets repel each other, and once the motor starts spinning, static air pressure is created in the gap. This allows the motor to operate without contact between the sleeve and the shaft. The sensorless motor has a standard operating voltage of 12 VDC and load current of approximately 70mA. Typical speed is 10,000 RPM and operating temperature ranges from 0 to 90 °C.