Stepping motor driver IC with integrated current sensing

The new motor driver IC device is intended for a broad variety of consumer applications including 3D printers, cameras, security cameras, portable printers, handheld scanners, pico-projectors and battery powered medical devices.

The IC can drive a micro-stepping motor of up to 128 steps and with a voltage ranging from 2.5 to 16V at currents of up to two amps. The output on-resistance (RDS(ON)) is only 0.48Ω as the TC78H670FTG uses Toshiba’s latest CDMOS process, thereby reducing voltage loss and heat generation inside the driver. An ultra-low standby current of just 0.1 µA prolongs battery life and the ability to operate with a 1.8 to 5.0V interface allows connection to a wide variety of hosts and microcontrollers. As a result, the device is suited for use in USB powered and battery powered applications as well as with standard nine to 12V system devices.

The micro-stepping control allows motors to be operated smoothly and quietly with reduced vibration and improved rotation angle accuracy. Safety features such as over current detection, thermal shut down and open-load detection are incorporated.

The sophisticated motor driver is housed in a compact QFN16 package with a footprint of just three by three millimetres which, along with the elimination of the two bulky and expensive current sense resistors by incorporating on-chip current detection, contributes to significant cost and space saving in designs.