New Industry Products

Stepping Motor Driver IC with Anti-Stall Feedback Architecture

April 19, 2017 by Jeff Shepard

Toshiba Corporation's Storage & Electronic Devices Solutions Company announced the launch of the TB67S289FTG, a stepping motor driver with a Toshiba developed architecture that automatically detects and prevents stalling during operation. Mass production is scheduled to begin in the end of July 2017.

Stable and highly precise control is a basic operating requirement, for motors used in printers, office appliances, banking terminals such as ATMs, cash dispensers, amusement machines, and home appliances. Recent demand has also emphasized more efficient motor drivers that use less power and generate less heat generation.

Avoiding stalls in stepping motor operation is the highest priority for securing stability and precision in motor control, and is achieved by provision of additional current to assure an operating margin for the motor. Real-time monitoring of motor torque and current feedback, using additional sensors and highly advanced MCU control, are also required to improve efficiency and heat generation.

A further way to improve efficiency and cut down heat generation is to adjust the built-in MOSFET's on-resistance and cut down power loss during operation.

The TB67S289FTG is the first stepping motor driver to apply Toshiba’s original anti-stall and efficiency improvement system, Active Gain Control (AGC), which enables the driver to monitor the motor and torque, and automatically optimizes motor control without additional MCU control. In operation, TB67S289FTG prevents motor stalls and automatically optimizes motor current, depending on torque needed. Compared with current solutions, TB67S289FTG cuts down the motor power by up to 80% at best, winning significant improvements in efficiency and heat improvement without relying on on-resistance.

Further efficiencies can also be achieved when the new stepping motor driver is supported by ACDS, Toshiba’s sense-resistor-free current monitor and control system, which allows more free space and uses fewer external components on the PCB.

Toshiba positions the TB67S289FTG as its flag-ship stepping motor driver, a high performance motor control and component reduction solution, and will continue to expand its line-up.

Main features include: 1. Anti-stall and high efficiency. Toshiba’s new motor control architecture AGC for anti-stall and high efficiency motor control. Plus sense-resistor-less current control ACDS for additional PCB space. High-resolution 1/32 step (max.) motor control cuts down noise and vibration.

2. Lower heat generation. Heat generation is reduced by low on-resistance (0.46Ω (upper + lower: typ.)).

3. Small package. Packaging in a small QFN package allows customers to reduce heat problems and simplify PCB design patterns for heat dissipation. It will also realize affordable solutions in terms of space and cost.

4. Built-in error detection circuits. Thermal shutdown, over-current shutdown, under voltage lock-out and motor load open detection circuits contribute to equipment safety and reliability. Also, error status can be flagged to MCU using error flag function.