TB67S103AFTG Datasheet, PDF (38/39 Pages) Toshiba Semiconductor – Serial-in controlled Bipolar Stepping Motor Driver

TB67S103AFTG/FNG
Points to remember on handling of ICs
Overcurrent detection Circuit
Overcurrent detection circuits (referred to as current limiter circuits) do not necessarily protect ICs under all
circumstances. If the overcurrent detection circuits operate against the overcurrent, clear the overcurrent status
immediately.
Depending on the method of use and usage conditions, exceeding absolute maximum ratings may cause the
overcurrent detection circuit to operate improperly or IC breakdown may occur before operation. In addition,
depending on the method of use and usage conditions, if overcurrent continues to flow for a long time after operation,
the IC may generate heat resulting in breakdown.
Thermal Shutdown Circuit
Thermal shutdown circuits do not necessarily protect ICs under all circumstances. If the thermal shutdown circuits
operate against the over-temperature, clear the heat generation status immediately.
Depending on the method of use and usage conditions, exceeding absolute maximum ratings may cause the thermal
shutdown circuit to operate improperly or IC breakdown to occur before operation.
Heat Radiation Design
When using an IC with large current flow such as power amp, regulator or driver, design the device so that heat is
appropriately radiated, in order not to exceed the specified junction temperature (TJ) at any time or under any
condition. These ICs generate heat even during normal use. An inadequate IC heat radiation design can lead to
decrease in IC life, deterioration of IC characteristics or IC breakdown. In addition, when designing the device, take
into consideration the effect of IC heat radiation with peripheral components.
Back-EMF
When a motor rotates in the reverse direction, stops or slows abruptly, current flows back to the motor’s power
supply owing to the effect of back-EMF. If the current sink capability of the power supply is small, the device’s motor
power supply and output pins might be exposed to conditions beyond the absolute maximum ratings. To avoid this
problem, take the effect of back-EMF into consideration in system design.
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2014-01-27