TC647B Microchip Technology Inc., TC647B Datasheet - Page 25

• Manufacturer Part Number: TC647B
• Description: Pwm Fan Speed Controllers With Minimum Fan Speed, Fan Restart And Fansense Technology For Fault Detection
• Manufacturer: Microchip Technology Inc.

FIGURE 5-13:
Bypass capacitor C
decouple the bias voltage. This is good to have, espe-
cially when using a MOSFET as the drive device. This
helps to give a localized low-impedance source for the
current required to charge the gate capacitance of Q
Two other bypass capacitors, labeled as C
added to decouple the V
were added simply to remove any noise present that
might cause false triggerings or PWM jitter. R
pull-up resistor for the FAULT output. The value for this
resistor is system-dependent.
2003 Microchip Technology Inc.
45.3 k
237 k
R
R
2
1
+5V
17.8 k
R
4
VDD
+5V
Design Example Schematic.
R
32.4 k
is added to the design to
3
IN
and V
0.01 µF
C
0.01 µF
C
B
C
1.0 µF
Thermometrics
100 k @25°C
NHQ104B425R5
B
F
MIN
2
3
1
V
C
V
IN
nodes. These
F
MIN
B
, were also
5
®
is the
TC647B
V
8
GND
1
DD
.
4
+
SENSE
C
1.0 µF
FAULT
VDD
V
OUT
6
7
5
TC642B/TC647B
R
10 k
5
C
0.1 µF
SENSE
R
3.0
SENSE
+12V
Fan
Q
SI2302
or
MGSF1N02E
DS21756B-page 25
Panasonic
12V, 140 mA
FBA06T12H
1
®