TB62779FNG Toshiba, TB62779FNG Datasheet - Page 19

• Manufacturer Part Number: TB62779FNG
• Manufacturer: Toshiba

Specifications of TB62779FNG

• Package: VSOP20
• # Outputs: 9
• Vout Max: 29V
• Io: 5.0 to 40mA
• Io Accuracy: ±6.0%
• Features Error Detection: -
• Features Gain Control: -
• Features Pwm Dimming: 7-bit
• Other Features & Functions: 2-wire interface
• Rohs Compatible Product(s) (#): Available

IC Usage Considerations
Points to remember on handling of ICs
Notes on handling of ICs
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The absolute maximum ratings of a semiconductor device are a set of ratings that must not be
exceeded, even for a moment. Do not exceed any of these ratings.
Exceeding the rating(s) may cause breakdown, damage or deterioration of the device, and may result
in injury by explosion or combustion.
Use an appropriate power supply fuse to ensure that a large current does not continuously flow in the
event of over current and/or IC failure. The IC will fully break down when used under conditions that
exceed its absolute maximum ratings, when the wiring is routed improperly, or when an abnormal
pulse noise occurs from the wiring or load, causing a large current to continuously flow. Such a
breakdown can lead to smoke or ignition. To minimize effects of a large current flow in the event of
breakdown, fuse capacity, fusing time, insertion circuit location, and other such suitable settings are
required.
If your design includes an inductive load such as a motor coil, incorporate a protection circuit into the
design to prevent device malfunction or breakdown caused by the current caused by inrush current at
power ON or the negative current caused by the back electromotive force at power OFF. IC
breakdown may cause injury, smoke or ignition.
For ICs with built-in protection functions, use a stable power supply. An unstable power supply may
cause the protection function to not operate, causing IC breakdown. IC breakdown may cause injury,
smoke or ignition.
Do not insert devices incorrectly or in the wrong orientation.
Make sure that the positive and negative terminals of power supplies are connected properly.
Otherwise, the current or power consumption may exceed the absolute maximum rating, and
exceeding the rating(s) may cause breakdown, damage or deterioration of the device, which may
result in injury by explosion or combustion.
In addition, do not use any device that has had current applied to it while inserted incorrectly or in
the wrong orientation even once.
Carefully select power amp, regulator, or other external components (such as inputs and negative
feedback capacitors) and load components (such as speakers),.
If there is a large amount of leakage current such as input or negative feedback capacitors, the IC
output DC voltage will increase. If this output voltage is connected to a speaker with low input
withstand voltage, overcurrent or IC failure can cause smoke or ignition. (The over current can cause
smoke or ignition from the IC itself.) In particular, please pay attention when using a Bridge Tied
Load (BTL) connection type IC that inputs output DC voltage to a speaker directly.
Heat Dissipation Design
In using an IC with large current flow such as a 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 or under any condition. These ICs generate heat even during normal use. An inadequate IC
heat dissipation design can lead to decrease in IC life, deterioration of IC characteristics or IC
breakdown. In addition, please design the device taking into consideration the effect of IC heat
dissipation on peripheral components.
Back-EMF
When a motor rotates in the reverse direction, stops, or slows down abruptly, a current flows 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
your system design.
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TB62779FNG
2010-07-21