Motor Control ICs Suit Variable Speed BLDC Applications

A line of brushless DC (BLDC) motor control ICs contain 115 Vac and 230 Vac devices that integrate six IGBT bridges for fractional and subfractional HP BLDC motors. With complementing bridge drivers, designers can reach scalable HP BLDC motor control for integral HP motors. The user-provided analog speed command modulates a three-phase distribution of PWM drive signals, preprocessed on-chip via external Hall sense signals. Motor speed is measured through use of a microcomputer timer or integrated with an op amp using the digital motor speed output signal, permitting variable motor speed control. A charge pump provides latch-free bias for the TOP Arm gates in a three-phase drive. HITACHI AMERICA LTD., Tarrytown, NY. (914) 631-0600.