emc2104 Standard Microsystems Corp., emc2104 Datasheet - Page 56

• Manufacturer Part Number: emc2104
• Description: Emc2104 Dual Rpm-based Pwm Fan Controller With Hardware Thermal Shutdown
• Manufacturer: Standard Microsystems Corp.

ADDR
APPLICATION NOTE: When the APD diode is enabled, there will be a delay of a full temperature update before
Revision 1.74 (05-08-08)
21h
6.10
R/W
R/W
Bit 3 - SYS3 - Enables the high temperature limit for the External Diode 3 channel to trigger the Critical
/ Thermal Shutdown circuitry (see
Bit 2 - SYS2 - Enables the high temperature limit for the External Diode 2 channel to trigger the Critical
/ Thermal Shutdown circuitry (see
Bit 1 - SYS1 - Enables the high temperature limit for the External Diode 1 channel to trigger the Critical
/ Thermal Shutdown circuitry (see
Bit 0 - APD - This bit enables the Anti-parallel diode functionality on the External Diode 3 pins (DP3
and DN3).
The Configuration 2 Register controls conversion rate of the temperature monitoring as well as the
fault queue. This register is software locked.
Bit 6 - DIS_DYN - Disables the Dynamic Averaging Feature.
Bit 5 - DIS_TO - Disables the SMBus time out function for the SMBus client (if enabled).
Bit 4 - DIS_AVG - Disables digital averaging of the External Diode 1 channel.
Bits 3-2 - QUEUE[1:0] - Determines the number of consecutive out of limit conditions that are
necessary to trigger an interrupt. Each measurement channel has a separate fault queue associated
with the high limit, low limit, and diode fault condition except the internal diode.
Configuration 2 Register
when the temperature drops below the high limit. The ALERT# pin will be asserted and released
normally.
‘0’ (default) - The Anti-parallel diode functionality is disabled. The External Diode 3 channel can be
configured for any type of diode
‘1’ - The Anti-parallel diode functionality is enabled. Both the External Diode 3 and 4 channels are
configured to support a diode or diode connected transistor (such as a 2N3904).
‘0’ (default) - The Dynamic Averaging function is enabled. The conversion time for all temperature
channels is scaled based on the chosen conversion rate to maximize accuracy and immunity to
random temperature measurement variation.
‘1’ - The Dynamic Averaging function is disabled. The conversion time for all temperature channels
is fixed regardless of the chosen conversion rate.
‘0’ (default) - The SMBus time out function is enabled.
‘1’ - The SMBus time out function is disabled allowing the device to be fully I
‘0’ (default) - The External Diode 1 channel has digital averaging enabled. The temperature data
is the average of the previous four measurements.
‘1’ - The External Diode 1 channel has digital averaging disabled. The temperature data is the last
measured data.
REGISTER
Config 2
any comparisons and functionality associated with the External Diode 4 channel will be
implemented. This includes the SYS4 bit operation, limit comparisons, and look up table
comparisons.
B7
-
Table 6.13 Configuration 2 Register
DIS_
DYN
B6
Section
Section
Section
DATASHEET
Dual RPM-Based PWM Fan Controller with Hardware Thermal Shutdown
DIS_
TO
B5
56
6.1).
6.1).
6.1).
DIS_
AVG
B4
QUEUE[1:0]
B3
B2
B1
CONV[1:0]
2
C compliant.
B0
SMSC EMC2104
Datasheet
DEFAULT
0Eh