tb6642fg TOSHIBA Semiconductor CORPORATION, tb6642fg Datasheet - Page 17

• Manufacturer Part Number: tb6642fg
• Description: Full-bridge Dc Motor Driver Ic
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Points to Remember on Handling of ICs
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Over Current Protection Circuit
Over current protection circuits (referred to as current limiter circuits) do not necessarily protect ICs
under all circumstances. If the Over current protection circuits operate against the over current, clear
the over current status immediately.
Depending on the method of use and usage conditions, such as exceeding absolute maximum ratings
can cause the over current protection circuit to not operate properly or IC breakdown before operation.
In addition, depending on the method of use and usage conditions, if over current 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, such as exceeding absolute maximum ratings
can cause the thermal shutdown circuit to not operate properly or IC breakdown before operation.
Heat Radiation Design
In using an IC with large current flow such as power amp, regulator or driver, please design the device
so that heat is appropriately radiated, not to exceed the specified junction temperature (T
and 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,
please design the device taking into considerate the effect of IC heat radiation with peripheral
components.
Back-EMF
When a motor rotates in the reverse direction, stops or slows down abruptly, a current flow
back to the motor’s power supply due 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 maximum ratings. To avoid this problem, take the effect of
back-EMF into consideration in system design.
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TB6642FG
2011-06-21
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