Dual RPM-Based PWM Fan Controller
Datasheet
Table 1.1 Pin Description for EMC2302 (continued)
PIN NUMBER
PIN NAME
PIN FUNCTION
PIN TYPE
Clock input for tachometer measurement
DI (5V)
Push Pull Clock output to other fan
controllers to synchronize Fan Speed
Control
9
CLK
DO
Active low interrupt - requires external
pull-up resistor.
10
ALERT#
OD (5V)
The pin types are described in detail below. All pins labeled with (5V) are 5V tolerant.
APPLICATION NOTE: For the 5V tolerant pins that have a pull-up resistor, the voltage difference between VDD and
the 5V tolerant pad must never be more than 3.6V.
Table 1.2 Pin Types
PIN TYPE
DESCRIPTION
Power
This pin is used to supply power or ground to the device.
Digital Input - this pin is used as a digital input. This pin is
5V tolerant.
DI
Push / Pull Digital Output - this pin is used as a digital
output. It can both source and sink current.
DO
Digital Input / Open Drain Output this pin is used as a
digital I/O. When it is used as an output, it is open drain
and requires a pull-up resistor. This pin is 5V tolerant.
DIOD
OD
Open Drain Digital Output - this pin is used as a digital
output. It is open drain and requires a pull-up resistor. This
pin is 5V tolerant.
Revision 1.1 (10-12-09)
8
SMSC EMC2302
DATASHEET
SMSC [ SMSC CORPORATION ]
