EMC2301 Standard Microsystems Corp., EMC2301 Datasheet - Page 40

• Manufacturer Part Number: EMC2301
• Description: Rpm-based Pwm Fan Controller
• Manufacturer: Standard Microsystems Corp.

Revision 1.2 (03-22-10)
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Zoom on
Output
Output
PWM
Update Time ends, PWM duty cycle changed
Output
PWM
Output
PWM
10x
PWM
10x
Spin Up Routine Ends – begins normal
27000
26800
26600
26400
26200
26000
25800
25600
25400
25200
25000
-50
Spin Time = 1.0s; Spin Level = 55%; Updated Time = 200ms;
t = 0
RPM Target from 0 RPM -> 8000 RPM @ time t = 0
RPM Target from 0 RPM -> 8000 RPM @ time t = 0
PWM Frequency vs. Ambient Temperature
Update Time = 200ms; Max Step = 16 PWM counts
V
DD
FSC Algorithm Spin Up Routine
operation
= 3.3V, Base Frequncy = 26Khz
FSC Algorithm PWM Ramping
0
Ambient Temperature (°C)
Duty Cycle Measured = 53.8%
Duty Cycle
T emp er at ur e ( C )
Measured
50
100
Update Time ends, PWM duty
cycle changed
150
DATASHEET
40
Zoom on
Output
PWM
Output
PWM
10x
27000
26800
26600
26400
26200
26000
25800
25600
25400
25200
25000
2.95
Spin Time = 1.0s; Spin Level = 50%; UpdateTime = 200ms;
t = 0
RPM Target from 0 RPM -> 8000 RPM @ time t = 0
FSC Algorithm Spin Up Routine – NoKick
3.05
PWM Frequency vs. Supply Voltage
TA = 25C, Base Frequncy = 26Khz
3.15
Duty Cycle Measured = 50%
Supply Voltage (V)
3.25
RPM-Based PWM Fan Controller
3.35
3.45
SMSC EMC2301
3.55
Datasheet
3.65