The LB1847 is a driver IC for stepper motors with PWM current control bipolar drive (fixed OFF time). A special feature of this IC is that VREF voltage is constant while the current can be set in 15 steps, allowing drive of motors ranging from 1-2 phase exciter types to 4W 1-2 phase exceiter types. The current decay pattern can also be selected (SLOW DECAY, FAST DECAY, MIX DECAY) to increase the decay of regenerative current at chopping OFF, thereby improving response characteristics. This is expecially useful for carriage and paper feed stepping motors in pricinters and similar applications where high-precision control and low vibrations are required.
