TB67H302HG Datasheet, PDF (22/23 Pages) Toshiba Semiconductor – Dual Bridge Driver IC for DC motor

TB67H302HG
Points to remember on handling of ICs
(1) 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.
(2) 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.
(3) 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 (Tj) at any time 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.
(4) 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 absolute maximum ratings.
To avoid this problem, take the effect of back-EMF into consideration in system design.
(5) Short-circuiting between outputs, air contamination faults, faults due to improper grounding, short-circuiting
between contiguous pins
Utmost care is necessary in the design of the power supply lines, GND lines, and output lines since the IC may
be destroyed by short-circuiting between outputs, air contamination faults, or faults due to improper grounding,
or by short-circuiting between contiguous pins. They may destroy not only the IC but also peripheral parts and
may contribute to injuries for users. Over current may continue to flow in the IC because of this destruction
and cause smoke or ignition of the IC. Expect the volume of this over current and add an appropriate power
supply fuse in order to minimize the effects of the over current. Capacity of the fuse, fusing time, and the
inserting position in the circuit should be configured suitably.
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2014-04-23