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MB91770 Series
28
DS07-16913-1E
Latch-up
Semiconductor devices are constructed by the formation of P-type and N-type areas on a substrate. When
subjected to abnormally high voltages, internal parasitic PNPN junctions (called thyristor structures) may be
formed, causing large current levels in excess of several hundred mA to flow continuously at the power supply
pin. This condition is called latch-up.
Note: The occurrence of latch-up not only causes loss of reliability in the semiconductor device, but can cause
injury or damage from high heat, smoke or flame. To prevent this from happening, do the following:
(1) Be sure that voltages applied to pins do not exceed the absolute maximum ratings. This should include
attention to abnormal noise, surge levels, etc.
(2) Be sure that abnormal current flows do not occur during the power-on sequence.
Observance of Safety Regulations and Standards
Most countries in the world have established standards and regulations regarding safety, protection from elec-
tromagnetic interference, etc. Customers are requested to observe applicable regulations and standards in the
design of products.
Fail-Safe Design
Any semiconductor devices have inherently a certain rate of failure. You must protect against injury, damage or
loss from such failures by incorporating safety design measures into your facility and equipment such as redun-
dancy, fire protection, and prevention of over-current levels and other abnormal operating conditions.
Precautions Related to Usage of Devices
FUJITSU MICROELECTRONICS semiconductor devices are intended for use in standard applications (com-
puters, office automation and other office equipment, industrial, communications, and measurement equipment,
personal or household devices, etc.).
CAUTION: Customers considering the use of our products in special applications where failure or abnormal
operation may directly affect human lives or cause physical injury or property damage, or where extremely high
levels of reliability are demanded (such as aerospace systems, atomic energy controls, sea floor repeaters,
vehicle operating controls, medical devices for life support, etc.) are requested to consult with FUJITSU MICRO-
ELECTRONICS sales representatives before such use. The company will not be responsible for damages arising
from such use without prior approval.