The TC78S122FTG is capable of running two stepping motors simultaneously. It can simultaneously drive two channels thanks to a low maximum on resistance of 0.6Ω (a reduction of 50% compared to previous products) that cuts heat generation. In previous products the regulator circuit for the IC’s internal logic operated at standby. The new product can stop the regulator at standby due to incorporation of a ‘Sleep’ function. Consequently, IC power consumption is reduced. The TC78S122FTG not only drives the stepping motors, but also provides an interface for driving brushed DC motors. For example, this could include one-channel for the stepping motor, and two channels for running brushed DC motors.
To provide reduced vibration and noise, the TC78S122FTG offers high-resolution motor driving of ¼ steps (max.) and a decay mode switching function for constant current control. Built-in error detection features include a thermal shutdown circuit and an overcurrent shutdown circuit to provide enhanced reliability and safety. The IC is housed in a compact QFN package that measures 7 x 7 x 0.9 mm.
Toshiba Electronics Europe; www.toshiba.semicon-storage.com