User's Manual

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SPR-8695TUH USB 2.0 HUB KBD
1. SPECIFICATION
1.1 SCOPE
This document describes the detail specifications for “SEJIN STD” TrackBall USB
keyboard
1.2. MECHANICAL PECIFICATION
1.2.1 Key switch
Operating system:
non-lock RUBBER tactile feeling.
Travel amount : 3.5±0.5mm with measuring load of 200gf applied.
Operating force : 55±25 gf
1.2.2 Key switch Operation
Key switch operating parameters should comply with those listed below.
Figure on the below represents typical pressure force and displacement values
acceptable to SEJIN. The force/displacement curve should not exhibit any significant
step or plateau from P2 to the end of full travel. Linear measures are in mm and the
values represent the force and displacement of a key switch after it has been preloaded
by 10 to 20 grams.
Standard: a. Non-lock rubber tactile feeling
b. P0 (Preloaded Point)
Travel = 0 mm / Force = 10 +10/-5 grams
c. P1 (Break over Point)
Travel = 1.15 ± 0.25 mm / Force = 60 ± 20 grams
d. P2 (Make Point)
Travel = 2.66 ± 0.25 mm / Force = P1 - Delta
Delta = 45% to 60% of the P1 force, but 20 grams minimum.
e. P3 (Normally End Point)
Travel = 3.8 ± 0.5 mm / Force = P1 + 10 to 15 grams
f. Total Displacement at 100 grams
Minimum = 3.2 mm, Nominal = 3.5 mm, Maximum = 4.8 mm
Check Point: a. Operating feeling: No definite stickiness or other abnormality shall be
allowed. When force is applied with a finger on the key-top center
at the rate of three times a second.
b. Key-top pulling strength: A key-top should come off after applying a
force of 0.5Kg to 8Kg range in the vertical direction.