In recent years, there have been increasing demands for further miniaturization and better environment resistance in the rotation angle sensor/encoder market.
Outlined below are our rotation angle sensor packaged in a compact size and excellent in the environment resistance (resistant to temperature/contamination/vibration).

Principle of angle detection

EM-3242 integrates multiple Hall elements which provide Hall voltage signals as shown in Figure 1 as the magnet (magnetic field) rotates. Using these sine wave (Vx) and cosine wave (Vy) analog signals that are shifted from each other by 90 degrees in phase, it performs a rotation calculation for (Vx, Vy) and judges the sign of the Y coordinate (Vy') of the vector after rotation to obtain a digitalized angular value. (Patent No. 4111813) This calculation method allows fast angle calculation by a small scale circuit without using ADC.

Output signal

A DAC is used to convert the digitalized angular value obtained by the above calculation to an analog signal,which is then output
from the IC.
As shown in Figure 2, the converted signal is proportional to the angle position