BD9132MUV Datasheet, PDF (14/17 Pages) Rohm – Output 2A or More High Efficiency Step-down Switching Regulator with Built-in Power MOSFET

●Cautions on use
1. Absolute Maximum Ratings
While utmost care is taken to quality control of this product, any application that may exceed some of the absolute maximum
ratings including the voltage applied and the operating temperature range may result in breakage. If broken, short-mode
or open-mode may not be identified. So if it is expected to encounter with special mode that may exceed the absolute
maximum ratings, it is requested to take necessary safety measures physically including insertion of fuses.
2. Electrical potential at GND
GND must be designed to have the lowest electrical potential In any operating conditions.
3. Short-circuiting between terminals, and mismounting
When mounting to pc board, care must be taken to avoid mistake in its orientation and alignment. Failure to do so may
result in IC breakdown. Short-circuiting due to foreign matters entered between output terminals, or between output and
power supply or GND may also cause breakdown.
4. Thermal shutdown protection circuit
Thermal shutdown protection circuit is the circuit designed to isolate the IC from thermal runaway, and not intended to
protect and guarantee the IC. So, the IC the thermal shutdown protection circuit of which is once activated should not be
used thereafter for any operation originally intended.
5. Inspection with the IC set to a pc board
If a capacitor must be connected to the pin of lower impedance during inspection with the IC set to a pc board, the capacitor
must be discharged after each process to avoid stress to the IC. For electrostatic protection, provide proper grounding to
assembling processes with special care taken in handling and storage. When connecting to jigs in the inspection process,
be sure to turn OFF the power supply before it is connected and removed.
6. Input to IC terminals
This is a monolithic IC with P⁺ isolation between P-substrate and each element as illustrated below. This P-layer and the
N-layer of each element form a P-N junction, and various parasitic element are formed.
If a resistor is joined to a transistor terminal as shown in Fig 37.
○P-N junction works as a parasitic diode if the following relationship is satisfied; GND>Terminal A (at resistor side), or
GND>Terminal B (at transistor side); and
○if GND>Terminal B (at NPN transistor side),
a parasitic NPN transistor is activated by N-layer of other element adjacent to the above-mentioned parasitic diode.
The structure of the IC inevitably forms parasitic elements, the activation of which may cause interference among circuits,
and/or malfunctions contributing to breakdown. It is therefore requested to take care not to use the device in such manner
that the voltage lower than GND (at P-substrate) may be applied to the input terminal, which may result in activation of
parasitic elements.
Pin A
N
N ^P+
Parasitic element
Resistor
Pin A
P
P⁺ _N
P substrate
GND
Transistor (NPN)
Pin B _C B
Pin B
E
Parasitic
element
N _P+
Parasitic element
N
P
P⁺ _N
P substrate
GND
GND
B
C
E
Parasitic
element
GND
Other adjacent elements
Fig.37 Simplified structure of monorisic IC
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