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Figure 5.16, "default, Step size with different update settings, User manual – SMSC EMC2102 User Manual

Page 21

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Fan Speed Control with the EMC2102 Device

SMSC EMC2102

USER MANUAL

Revision 0.2 (09-17-07)

21

In the next experiment (

Figure 5.17, "Default UPDATE with Different Step Size Settings"

), two different

maximum step sizes, 16 and 63, were used. with the 63 STEP SIZE setting, the output takes less
steps (updates) from 4000 rpm to 7500 rpm because it gives the fan more power to follow the desired
rpm settings.

In the last experiment, an extremely slow ramp rate is demonstrated. The UPDATE was set to
maximum (1600 ms), and the STEP SIZE was changed to 01h (

Figure 5.18, "Exceptionally Slow

Rate"

). Note the large scale of the “Time per division” in the figure.

Figure 5.16 Default Step Size with Different UPDATE Settings

Figure 5.17 Default UPDATE with Different Step Size Settings

UPDATE
= 400 ms

UPDATE
= 100 ms

STEp SIZE

= 63

STEp SIZE

= 16