62707 MS IM B8-9164 / 80102 AS (OT) No.7256-1/14

http://onsemi.com

Semiconductor Components Industries, LLC, 2013

May, 2013

LB11870

Overview

The LB11870 is a three-phase brushless motor driver developed for driving the motors used with the polygonal

mirror in laser printers and plain paper copiers. It can implement, with a single IC chip, all the circuits required

for polygonal mirror drive, including speed control and driver functions. The LB11870 can implement motor drive

with minimal power loss due to its use of direct PWM drive.

Functions

• Three-phase bipolar drive

• Direct PWM drive

• Includes six high and low side diodes on chip.

• Output current control circuit

• PLL speed control circuit

• Phase lock detection output (with masking function)

• Includes current limiter, thermal protection, rotor constraint protection, and low-voltage protection circuits on chip.

• Deceleration type switching circuit (free running or reverse torque)

• PWM oscillator

• Power saving circuit

Ordering number : EN7256A

Monolithic Digital IC

For Polygonal Mirror Motors

Three-Phase Brushless Motor Driver