3 General Safety Precautions and Usage Considerations
3-1
3. General Safety Precautions and Usage Considerations
This section is designed to help you gain a better understanding of semiconductor devices, so as to
ensure the safety, quality and reliability of the devices which you incorporate into your designs.
3.1
From Incoming to Shipping
3.1.1
Electrostatic discharge (ESD)
When handling individual devices (which are not yet mounted on a printed
circuit board), be sure that the environment is protected against
electrostatic electricity. Operators should wear anti-static clothing, and
containers and other objects which come into direct contact with devices
should be made of anti-static materials and should be grounded to earth via
an 0.5- to 1.0-M
Ω
protective resistor.
Please follow the precautions described below; this is particularly important
for devices which are marked “Be careful of static.”.
(1)
Work environment
•
When humidity in the working environment decreases, the human body and other insulators
can easily become charged with static electricity due to friction. Maintain the recommended
humidity of 40% to 60% in the work environment, while also taking into account the fact that
moisture-proof-packed products may absorb moisture after unpacking.
•
Be sure that all equipment, jigs and tools in the working area are grounded to earth.
•
Place a conductive mat over the floor of the work area, or take other appropriate measures, so
that the floor surface is protected against static electricity and is grounded to earth. The surface
resistivity should be 10
4
to 10
8
Ω
/sq and the resistance between surface and ground, 7.5
×
10
5
to
10
8
Ω
•
Cover the workbench surface also with a conductive mat (with a surface resistivity of 10
4
to
10
8
Ω
/sq, for a resistance between surface and ground of 7.5
×
10
5
to 10
8
Ω
) . The purpose of this
is to disperse static electricity on the surface (through resistive components) and ground it to
earth. Workbench surfaces must not be constructed of low-resistance metallic materials that
allow rapid static discharge when a charged device touches them directly.
•
Pay attention to the following points when using automatic equipment in your workplace:
(a) When picking up ICs with a vacuum unit, use a conductive rubber fitting on the end of the
pick-up wand to protect against electrostatic charge.
(b) Minimize friction on IC package surfaces. If some rubbing is unavoidable due to the device’s
mechanical structure, minimize the friction plane or use material with a small friction
coefficient and low electrical resistance. Also, consider the use of an ionizer.
(c) In sections which come into contact with device lead terminals, use a material which
dissipates static electricity.
(d) Ensure that no statically charged bodies (such as work clothes or the human body) touch
the devices.
Summary of Contents for TMPR7901
Page 1: ...TX System RISC TX79 Family TMPR7901 Symmetric 2 way superscalar 64 bit CPU ...
Page 14: ...Handling Precautions ...
Page 15: ......
Page 17: ...1 Using Toshiba Semiconductors Safely 1 2 ...
Page 41: ...4 Precautions and Usage Considerations 4 2 ...
Page 42: ...TX7901 User s Manual Rev 6 30T November 2001 DOCUMENT NUMBER M 99 00004 07 ...
Page 43: ......
Page 259: ...Chapter 13 Removed TX7901 User s Manual Rev 6 30T Nov 2001 13 1 13 Removed ...
Page 260: ...Chapter 13 Removed TX7901 User s Manual Rev 6 30T Nov 2001 13 2 ...