Technical Note
BU7861KN
●Notes for use
1) Absolute maximum ratings
When applied voltage (VDD and VIN), and the operating temperature range (Topr) and the like it exceeds absolute
maximum rating, there is a possibility of destroying, Because it cannot specify destructive mode such as short circuit or
opening, when special mode which exceeds absolute maximum rating is supposed, that physical safety measure such as
a fuse should be implemented.
2) Recommendation operating range
If it is this range, it is the range which almost can obtain the quality of according to expectation. Concerning electric
quality ，being something which is guaranteed under condition of each item. Even inside the recommendation operating
range, voltage, temperature characteristic is shown.
3) About the opposite connection of the power source connector
There is a possibility of destroying LSI with the opposite connection to the power source connector. Please administer the
measure such as the diode is inserted between power source and the power source terminal of LSI outside as the
protection for opposite connection destruction.
4) About the power source line
At the time of designing the baseplate pattern, as for wiring of the power source/GND line, please make sure to become
low impedance. At that time, even digital type power source and analog type power source being the same electric
potential, please separate digital type power source pattern and analog type power source pattern, control the turning of
digital noise to the analog power source due to the common impedance of wiring pattern. Concerning the GND line, please
consider the similar pattern design. In addition, concerning all power source terminals of LSI, the condenser is inserted
between power source and the GND terminal, in the case of electrolysis condenser use, please decide constant with
sufficient verification in regard to the fact of without being problem in qualities of the condenser which is used, such as the
capacity pulling out happens in low temperature.
5) About GND voltage
As for electric potential of the GND terminal regarding what ever working condition, please make sure to become lowest
electric potential. In addition, please really verify that does not have the terminal which becomes electric potential below
GND include transient phenomenon
6) About the short circuit between the terminal and error installing
The occasion where you install in the set baseplate, please pay attention to the direction and the position gap of LSI
sufficiently. when you install with mistake, there is a possibility of LSI destroying. In addition, there is a possibility of
destruction concerning when it short-circuits e.g. due to the foreign material enters between the terminal and between
terminal and power source and GND.
7) About the operation in the strong electromagnetic field
As for the use in the strong electromagnetic field, being to be a possibility of doing the malfunction, please note.
8) About the testing with the set baseplate
When inspecting with the set baseplate, the condenser is connected to the LSI terminal whose impedance is low, because
there is a possibility of stress depending on LSI, please be sure to do discharge in every process. In addition, when
installing and removing the tool in inspection process, by all means with power source as off to connect, to inspect, to
remove. Furthermore, As a static electricity measure, please note to administer the earth and the conveyance and
preservation in the case of assemble process sufficiently.
9) About each input terminal
With respect to the structure of LSI, the parasitic element is formed inevitably by the relationship of electric potential. It
causes the interference of circuit operation due to the fact that the parasitic element operates, the malfunction, even can
become cause of destruction. Therefore, e.g., the voltage which is lower than GND in the input terminal is impressed,
please note sufficiently not to do the method where the parasitic element operates. In addition, When not impress power
supply voltage in LSI, please do not impress voltage in the input terminal. Furthermore, when power supply voltage is
impressed even, as for each input terminal, please make voltage below power supply voltage or within guaranteed
performance of electric quality.
10) About GND wiring pattern
When there are both small signal GND and a heavy-current GND, it separates small signal GND pattern from
heavy-current GND pattern, in order that the pattern wiring and the voltage change caused by large current do not change
the voltage of small-signal GND, it is recommended to carry out the one-point grounding at the reference point of set..
Please be careful of not to fluctuate the GND wiring pattern of external parts
11) When in the external condenser, the ceramic condenser is used, please decide the constant on the consideration of the
nominal capacity decrease caused by direct current bias and the change of the capacity due to temperature etc.
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2010.09 - Rev.A
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