emc2103-3-kp-tr Standard Microsystems Corp., emc2103-3-kp-tr Datasheet - Page 24

• Manufacturer Part Number: emc2103-3-kp-tr
• Description: Emc2103 Rpm-based Fan Controller With Hardware Thermal Shutdown
• Manufacturer: Standard Microsystems Corp.

Revision 0.88 (06-30-08)
5.2
Fan Driver Setting (read
/ write)
EDGES[1:0]
-
UPDATE[2:0]
(Fan Configuration)
LEVEL
(Spin Up Configuration)
SPINUP_TIME[1:0]
(Spin Up Configuration)
Fan Step
-
SETTING MODE
DIRECT PWM
The EMC2103 has four modes of operation for the fan driver. Each mode uses Ramp Rate control and
the Spin Up Routine
1. PWM Setting Mode - in this mode of operation, the user directly controls the PWM duty cycle
2. Fan Speed Control Mode (FSC) - in this mode of operation, the user determines a fan speed and
3. Using the Look Up Table with Fan Drive Settings (PWM Setting w/ LUT Mode) - In this mode of
4. Using the Look Up Table with Fan Speed Control algorithm (FSC w/ LUT Mode)- In this mode of
Fan Control Modes of Operation
setting. Updating the Fan Driver Setting Register (see
drive.
the drive setting is automatically updated to achieve this target speed.
operation, the user programs the Look Up Table with PWM duty cycle settings and corresponding
temperature thresholds. The fan drive is set based on the measured temperatures and the
corresponding drive settings.
operation, the user programs the Look Up Table with fan speed target values and corresponding
temperature thresholds. The TACH Target Register will be set based on the measured
temperatures and the corresponding target settings. The PWM drive settings will be determined
automatically based on the RPM based Fan Speed Control Algorithm
This is the default mode. The PWM Setting Mode is enabled by clearing both the EN_ALGO
bit in the Fan Configuration Register (see
Up Table Configuration Register (see
Whenever the PWM Setting Mode is enabled the current drive will be changed to what was
last written into the Fan Driver Setting Register.
This mode is enabled by clearing the LUT_LOCK bit in the Look Up Table (LUT)
Configuration Register and setting the EN_ALGO bit in the Fan Configuration Register.
This mode is enabled by programming the Look Up Table then setting the LUT_LOCK bit
while the RPM / PWM bit is set to a ‘1’ (see
This mode is enabled by programming the Look Up Table then setting the LUT_LOCK bit
while the RPM / PWM bit is set to ‘0’ (see
Fan Driver Setting (read
only)
EDGES[1:0]
(Fan Configuration)
RANGE[1:0]
(Fan Configuration)
UPDATE[2:0]
(Fan Configuration)
LEVEL
(Spin Up Configuration)
SPINUP_TIME[1:0]
(Spin Up Configuration)
Fan Step
Fan Minimum Drive
Table 5.3 Fan Controls Active for Operating Mode
FSC MODE
DATASHEET
24
Fan Driver Setting (read only)
EDGES[1:0]
-
UPDATE[2:0]
(Fan Configuration)
LEVEL
(Spin Up Configuration)
SPINUP_TIME[1:0]
(Spin Up Configuration)
Fan Step
DIRECT PWM SETTING W/
Section
LUT MODE
Section
RPM-Based Fan Controller with HW Thermal Shutdown
Section
Section
6.32).
Section
6.22) and the LUT_LOCK bit in the Look
6.32).
6.32)
6.20) will instantly update the fan
Fan Driver Setting (read
only)
EDGES[1:0]
RANGE[1:0]
(Fan Configuration)
UPDATE[2:0]
(Fan Configuration)
LEVEL
(Spin Up Configuration)
SPINUP_TIME[1:0]
(Spin Up Configuration)
Fan Step
Fan Minimum Drive
FSC W/ LUT MODE
SMSC EMC2103
Datasheet