Motor driver ICs
FPin descriptions
BA6870S
FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC1 = 5V, VM = VCC2 = 12V)
FCircuit operation
(1) Pseudo-linear output and torque ripple cancellation
The IC generates a trapezoidal (pseudo-linear) output
current, whose waveform phase is 30 degrees ahead of
that of the Hall input voltage (Fig. 1).
The trapezoidal waveform of output current would create
intermittence in the magnetic field generated by the
3-phase motor, and would result in an irregular rotation
of the motor. To prevent this, the output waveform is ob-
tained by superimposing a triangular wave on the trape-
zoidal wave (Fig. 2). This process is called torque ripple
cancellation.
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