Staticsensitive Components

The following precautions are applicable when performing any maintenance involving internal access to the instrument.

Static discharge can damage any semiconductor component in this instrument.

This instrument contains electrical components that are susceptible to damage from static discharge. Table 6-1 lists the relative susceptibility of various classes of semiconductors. Static voltages of 1 kV to 30 kV are common in unprotected environments.

When performing maintenance observe the following precautions to avoid component damage:

1. Minimize handling of static-sensitive components.

2. Transport and store static-sensitive components or assemblies in their original containers or on a metal rail. Label any package that contains static-sensitive components or assemblies.

3. Discharge the static voltage from your body by wearing a grounded antistatic wrist strap while handling these components. Servicing static-sensitive components or assemblies should be performed only at a static-free work station by qualified service personnel.

4. Nothing capable of generating or holding a static charge should be allowed on the work station surface.

Table 6-1

Relative Susceptibility to Static-Discharge Damage

Table 6-1

Semiconductor Classes

Relative Susceptibility Levels3

MOS or CMOS microcircuits or discretes, or linear microcircuits with MOS inputs (Most Sensitive)

1

ECL

2

Schottky signal diodes

3

Schottky TTL

4

High-frequency bipolar transistors

5

JFET

6

Linear microcircuits

7

Low-power Schottky TTL

8

TTL (Least Sensitive)

9

aVoltage equivalent for levels (voltage discharged from a 100-pF capacitor through a resistance of 100 ii):

aVoltage equivalent for levels (voltage discharged from a 100-pF capacitor through a resistance of 100 ii):

5. Keep the component leads shorted together whenever possible.

6. Pick up components by their bodies, never by their leads.

7. Do not slide the components over any surface.

8. Avoid handling components in areas that have a floor or work-surface covering capable of generating a static charge.

PREVENTIVE

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