MIC502 Micrel Semiconductor, MIC502 Datasheet - Page 2

• Manufacturer Part Number: MIC502
• Description: Fan Management IC Advance Information
• Manufacturer: Micrel Semiconductor

MIC502
Pin Configuration
Pin Description
MIC502
Pin Number
1
2
3
4
5
6
7
8
Pin Name
VSLP
GND
/OTF
OUT
VDD
VT1
VT2
CF
VSLP
GND
VT1
CF
Pin Function
Thermistor 1 (Input): Analog input of approximately 30% to 70% of V
produces active duty cycle of 0% to 100% at driver output (OUT). Connect to
external thermistor network (or other temperature sensor). Pull low for
shutdown.
PWM Timing Capacitor (External Component): Positive terminal for the
PWM triangle-wave generator timing capacitor. The recommended C
0.1 F for 30Hz PWM operation.
Sleep Threshold (Input): The voltage on this pin is compared to V
When V
V
disables the sleep-mode function.
Ground
Thermistor 2 (Input): Analog input of approximately 30% to 70% of V
produces active duty cycle of 0% to 100% at driver output (OUT). Connect to
motherboard fan control signal or second temperature sensor.
Overtemperature Fault (Output): Open-collector output (active low).
Indicates overtemperature fault condition (V
Driver Output: Asymmetical-drive active-high complimentary PWM output.
Typically connect to base of external NPN motor control transistor.
Power Supply (Input): IC supply input; may be independent of fan power
supply.
T2
1
2
3
4
8-Pin SOIC (M)
8-Pin DIP (N)
rises above V
T1
164
< V
SLP
WAKE
and V
8
7
6
5
. (V
VDD
OUT
OTF
VT2
T2
< V
WAKE
SLP
= V
the MIC502 enters sleep mode until V
SLP
+ V
T1
HYST
> V
.) Grounding VSLP
OT
) when active.
T1
and V
DD
May 1999
F
DD
is
T1
Micrel
T2
or
.