Document Number: 002-04713 Rev.*A
Page 26 of 65
MB96640 Series
12. Handling Precautions
Any semiconductor devices have inherently a certain rate of failure. The possibility of failure is greatly affected by the conditions in
which they are used (circuit conditions, environmental conditions, etc.). This page describes precautions that must be observed to
minimize the chance of failure and to obtain higher reliability from your Cypress semiconductor devices.
12.1 Precautions for Product Design
This section describes precautions when designing electronic equipment using semiconductor devices.
Absolute Maximum Ratings
Semiconductor devices can be permanently damaged by application of stress (voltage, current, temperature, etc.) in excess of
certain established limits, called absolute maximum ratings. Do not exceed these ratings.
Recommended Operating Conditions
Recommended operating conditions are normal operating ranges for the semiconductor device. All the device's electrical
characteristics are warranted when operated within these ranges.
Always use semiconductor devices within the recommended operating conditions. Operation outside these ranges may adversely
affect reliability and could result in device failure.
No warranty is made with respect to uses, operating conditions, or combinations not represented on the data sheet. Users
considering application outside the listed conditions are advised to contact their sales representative beforehand.
Processing and Protection of Pins
These precautions must be followed when handling the pins which connect semiconductor devices to power supply and input/output
functions.
1. Preventing Over-Voltage and Over-Current Conditions
Exposure to voltage or current levels in excess of maximum ratings at any pin is likely to cause deterioration within the device,
and in extreme cases leads to permanent damage of the device. Try to prevent such overvoltage or over-current conditions at
the design stage.
2. Protection of Output Pins
Shorting of output pins to supply pins or other output pins, or connection to large capacitance can cause large current flows.
Such conditions if present for extended periods of time can damage the device.
Therefore, avoid this type of connection.
3. Handling of Unused Input Pins
Unconnected input pins with very high impedance levels can adversely affect stability of operation. Such pins should be
connected through an appropriate resistance to a power supply pin or ground pin.
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.
CAUTION: 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 electromagnetic
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 redundancy, fire protection, and
prevention of over-current levels and other abnormal operating conditions.
