EMC2103-2-AP-TR Standard Microsystems (SMSC), EMC2103-2-AP-TR Datasheet - Page 22

• Manufacturer Part Number: EMC2103-2-AP-TR
• Description: CLOSED LOOP RPM FAN CONTROLLER
• Manufacturer: Standard Microsystems (SMSC)

PULL UP RESISTOR
< 4.7k Ohm
> 33k Ohm
6.8k Ohm
10k Ohm
15k Ohm
22k Ohm
.
APPLICATION NOTE: Current only flows when the TRIP_SET pin is being monitored. At all other times, the internal
APPLICATION NOTE: The TRIP_SET pin circuitry is designed to use a 1% resistor externally. Using a 1% resistor
Revision 0.88 (06-30-08)
5.1.1
5.1.2
SHDN_SEL Pin
The EMC2103 has a ‘strappable’ input (SHDN_SEL) allowing for configuration of the hardware
Critical/Thermal Shutdown input channel. The pull-up resistor used on this pin identifies which
configuration setting is used as shown in
Note 5.1
TRIP_SET Pin
The EMC2103’s TRIP_SET pin is an analog input to the Critical/Thermal Shutdown block which sets
the Thermal Shutdown temperature. The system designer creates a voltage level at the input through
a simple resistor connected to GND as shown in
an input voltage on the TRIP_SET pin which is translated into a temperature ranging from 65°C to
127°C as shown in
Intel CPU on External
Intel CPU on External
Intel CPU on External
MODE/SHUTDOWN
2N3904 on External
External Diode 1
Internal Diode
AMD CPU on
Diode 2 - see
CHANNEL
Note 5.1
Diode 1
Diode 1
Diode 1
reference voltage is removed and the TRIP_SET pin will be pulled down to ground.
will result in the Thermal / Critical Shutdown temperature being decoded correctly. If a 5%
resistor is used, then the Thermal / Critical Shutdown temperature may be decoded with as
much as ±1°C error.
For the EMC2103-1, the decode for a 22k Ohm resistor on the SHDN_SEL pin will be to
use the External Diode 1 channel in Diode Mode (the same as the decode for a 6.8k Ohm
resistor) as the hardware shutdown device.
Table 5.2
Table 5.1 SHDN_SEL Pin Decode
Beta Compensation enabled and set to
Beta and REC controls are not locked
Beta Compensation enabled (auto)
Beta Compensation enabled (auto)
Beta and REC controls are locked
Beta and REC controls are locked
Beta and REC controls are locked
Beta and REC controls are locked
Beta and REC controls are locked
EXTERNAL DIODE 1 CONFIG
Beta Compensation disabled
Beta Compensation disabled
Beta Compensation disabled
DATASHEET
REC disabled
REC enabled
REC enabled
REC enabled
REC enabled
REC enabled
Table
22
auto
5.1.
Figure
RPM-Based Fan Controller with HW Thermal Shutdown
5.2. The value of this resistor is used to create
Beta and REC controls are not locked
Beta and REC controls are not locked
Beta and REC controls are not locked
Beta and REC controls are not locked
Beta and REC controls are not locked
Beta Compensation enabled (auto)
Beta Compensation enabled (auto)
Beta Compensation enabled (auto)
Beta Compensation enabled (auto)
Beta Compensation enabled (auto)
Beta Compensation enabled (auto)
Beta and REC controls are locked
EXTERNAL DIODE 2 CONFIG
REC enabled
REC enabled
REC enabled
REC enabled
REC enabled
REC enabled
SMSC EMC2103
Datasheet