BD95242MUV ROHM Electronics, BD95242MUV Datasheet - Page 18

• Manufacturer Part Number: BD95242MUV
• Description: 2ch Switching Regurators for Desktop PC
• Manufacturer: ROHM Electronics

●Operation Notes and Precautions
© 2009 ROHM Co., Ltd. All rights reserved.
www.rohm.com
1. This integrated circuit is a monolithic IC, which (as shown in the figure below), has P isolation in the P substrate and
2. In some modes of operation, power supply voltage and pin voltage are reversed, giving rise to possible internal circuit
3. Absolute maximum rating
4.GND potential
5. Thermal design
6. Short-circuits between pins and incorrect mounting position
Parasitic diodes inevitably occur in the structure of the IC. The operation of parasitic diodes can result in mutual
interference among circuits, as well as operating malfunctions and physical damage. Therefore, be careful to avoid
methods by which parasitic diodes operate, such as applying a voltage lower than the GND (P substrate) voltage to an
input pin.
Although the quality of this IC is rigorously controlled, the IC may be destroyed when applied voltage or operating
temperature exceeds its absolute maximum rating. Because short mode or open mode cannot be specified when the IC is
destroyed, it is important to take physical safety measures such as fusing if a special mode in excess of absolute rating
limits is to be implemented.
Make sure the potential for the GND pin is always kept lower than the potentials of all other pins, regardless of the
operating mode.
In order to build sufficient margin into the thermal design, give proper consideration to the allowable loss (Power
Dissipation) in actual operation.
When mounting the IC onto the circuit board, be extremely careful about the orientation and position of the IC. The IC may
be destroyed if it is incorrectly positioned for mounting. Do not short-circuit between any output pin and supply pin or
ground, or between the output pins themselves. Accidental attachment of small objects on these pins will cause shorts and
may damage the IC.
between the various pins. A P-N junction is formed from this P layer and N layer of each pin, with the type of junction
depending on the relation between each potential, as follows:
damage. For example, when the external capacitor is charged, the electric charge can cause a VCC short circuit to the
GND. In order to avoid these problems, inserting a VCC series countercurrent prevention diode or bypass diode between
the various pins and the VCC is recommended.
・When GND＞ element A＞ element B, the P-N junction is a diode.
・When element B＞GND element A, the P-N junction operates as a parasitic transistor.
Parasitic element
Pin A
N
P
+
N
GND
P
P substrate
P
+
N
Resistor
Countercurrent
Pin A
Bypass diode
Parasitic
element
VCC
18/20
Parasitic element
Pin B
N
P
+
Pin
C
B
N
E
GND
P
P substrate
Transistor (NPN)
P
+
N
GND
Other adjacent elements
Pin B
B
Technical Note
2009.04 - Rev.B
C
E
GND
Parasitic
element