User's Manual

SEJIN ELECTRON, INC

This Document contains proprietary to Sejin Electron, Inc. Use or disclosure without written

permission from an officer of Sejin is expressly forbidden.

Document number : R-FB-0

Page 5/13

Issued date : 2009-02-11

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 = 0.8 ± 0.3 mm / Force = 45 ± 15 grams

d. P2 (Make Point)

Travel = 1.75 ± 0.95 mm / Force = P1 - Delta

Delta = 45% to 60% of the P1 force, but 20 grams minimum.

e. P3 (Normally End Point)

Travel = 2.5 ± 0.5 mm / Force = P1 + 10 to 15 grams

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.