TBMA800 Test Boards Monolithic Power Systems (MPS) TBMA800 Test Boards provide a demonstration platform for the MagAlpha MA800 8-Bit Contactless Angle Sensor. The MA800 is designed to replace analogic potentiometers or rotary switches. The MA800 Sensor detects the absolute angular position of a permanent magnet attached to a rotating shaft. Since the measurement is spatially confined, the user has flexibility in terms of magnet shapes and configurations.