EMC2305 Datasheet, PDF (8/55 Pages) SMSC Corporation – Multiple RPM-Based PWM Fan Controller for Five Fans

PIN NUMBER
6
7
8
9
10
11
12
13
14
15
16
Bottom Pad
Multiple RPM-Based PWM Fan Controller for Five Fans
Datasheet
Table 1.1 Pin Description for EMC2305 (continued)
PIN NAME
PIN FUNCTION
PIN TYPE
TACH1
PWM2
TACH2
PWM3
TACH3
CLK
ALERT#
PWM4
TACH4
PWM5
TACH5
GND
Open drain tachometer input for Fan 1-
requires pull-up resistor
Push-Pull PWM output driver for Fan 2
Open Drain PWM output driver for Fan 2
Open drain tachometer input for Fan 2 -
requires pull-up resistor
Push-Pull PWM output driver for Fan 3
Open Drain PWM output driver for Fan 3
Open drain tachometer input for Fan 3 -
requires pull-up resistor
Clock input for tachometer measurement
Push Pull Clock output to other fan
controllers to synchronize Fan Speed
Control
Active low interrupt - requires external
pull-up resistor.
Push-Pull PWM output driver for Fan 4
Open Drain PWM output driver for Fan 4
Open drain tachometer input for Fan 4 -
requires pull-up resistor
Push-Pull PWM output driver for Fan 5
Open Drain PWM output driver for Fan 5
Open drain tachometer input for Fan 5 -
requires pull-up resistor
Ground
DI (5V)
DO
OD (5V)
DI (5V)
DO
OD (5V)
DI (5V)
DI (5V)
DO
OD (5V)
DO
OD (5V)
DI (5V)
DO
OD (5V)
DI (5V)
Power
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.
Revision 1.1 (10-12-09)
8
DATASHEET
SMSC EMC2305