EMC2101-R-ACZL-TR datasheet(47/57 Pages) SMSC

47 / 57 page

SMBus Fan Control with 1°C Accurate Temperature Monitoring

Datasheet

SMSC EMC2101

Revision 2.54 (06-16-09)

DATASHEET

The table should be loaded with the lowest temperature in the T1 register (50h) and increasing in

temperature for all settings.

See Section 5.6.4 for description of the Fan Control Look Up Table operation. The fan speed settings

for each temperature threshold follow the same behavior as the Fan Setting Register (see

Section 6.18).

6.23

Averaging Filter Register

The Averaging Filter Register controls the level of digital averaging that is used for the External Diode

temperature measurements as well as the configuration of the ALERT / TACH pin functionality.

Bit 2 - 1 - FILTER[1:0] - control the level of digital filtering that is applied to the External Diode

temperature measurements as shown in Table 6.30. See Figure 5.5 and Figure 5.6 for examples on

the filter behavior.

Bit 0 - ALERT_COMP - determines the functionality of the ALERT / TACH pin.

‘0’ (default) - the ALERT / TACH pin is configured to act as an interrupt (see Section 5.4.2).

‘1’ - the ALERT / TACH pin is configured to operate as a temperature comparator (see

Section 5.4.1).

Table 6.29 Averaging Filter Register

ADDR.

R/W

DEFAULT

BFh

R/W

Averaging Filter

FILTER[1:0]

ALERT_

COMP

00h

Table 6.30 Averaging Settings

FILTER[1:0]

AVERAGING

Disabled (default)

Level 1

Level 2

EMC2101-R-ACZL-TR 데이터시트(PDF) 47 Page - SMSC Corporation