Data Sheet

TB6560AHQ/AFG
2014-10-01
33
Points to Remember on Handling of ICs
(1) 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.
(2) 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
J
) 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.
(3) 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.
(4) Short-Circuits
The IC may be permanently damaged in case of a short-circuit across its outputs, a short-circuit to
power supply or a short-circuit to ground. These possibilities should be fully considered in the design
of the output, V
DD
, VM and ground lines.
(5) Short-Circuits between Adjacent Pins in the TB6560AHQ
In the TB6560AHQ, the term “adjacent pin” includes a pin diagonally closest to a given pin. For
example, pin 3 has four adjacent pins: 1, 2, 4 and 5.
Depending on the specified voltage and current, a large current might abruptly flow through the
TB6560AHQ in case of a short-circuit between any adjacent pins that are listed below. If the large
current persists, it may lead to a smoke emission.
1) Pins 7 and 8
2) Pins 7 and 9
3) Pins 8 and 9
4) Pins 9 and 10
5) Pins 9 and 11
6) Pins 10 and 12
7) Pins 11 and 12
8) Pins 11 and 13
9) Pins 12 and 13
10) Pins 12 and 14
11) Pins 13 and 14
12) Pins 13 and 15
13) Pins 14 and 16
14) Pins 15 and 16
15) Pins 16 and 17
16) Pins 16 and 18
17) Pins 17 and 18
18) Pins 18 and 19
19) Pins 18 and 20
Therefore, to avoid a continuous overcurrent due to the above-described short-circuit and allow the
TB6560AHQ/AFG to be fail-safe, an appropriate fuse should be added at the right place, or
overcurrent shutdown circuitry should be added to the power supply. The rated current of a fuse may
vary depending on actual applications and its characteristics. Thus, an appropriate fuse must be
selected experimentally.