The LB11873 is a 3-phase brushless motor driver developed for driving the polygonal mirror motor used in plain-paper copiers and similar products. This IC can implement the circuits required for polygonal mirror motor drive (speed control and driver circuits) in a single chip. The LB11873 implements low-noise/low-vibration PWM drive by changing the current at phase switching gradually to reduce motor noise.

• Three-phase bipolar drive (quiet direct PWM)
• PLL speed control circuit
• Hall sensor FG support
• Dedicated external clock
• Brake mode switching circuit (free running and reverse braking)
• Phase lock detection output (with masking function)
• Built-in current limiter, constraint protection, undervoltage protection, thermal protection, and CLK line disconnection protection circuits
• Input pins support 3V system microcontrollers