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FAN8408D
2 Phase Half Wave BLDC Motor Driver
Features
•
•
•
•
•
•
•
A wide range of operation voltage: 4V to 15V
Built-in motor lock detector.
Automatic restart function
Hall output for a motor speed detection
Built-in thermal shut down circuits
Built-in reverse current protection diode
Compact package: 8-SOP-225
Description
The FAN8408D is a monolithic integrated circuit, and
suitable for DC cooling fan motors.
8-SOP-225
1
Typical Applications
• DC cooling fan motor
Ordering Information
Device
FAN8408D
FAN8408DTF
Package
8-SOP-225
8-SOP-225
Operating Temp.
−25°C
~ 85°C
−25°C
~ 85°C
Rev.1.0.4
©2002 Fairchild Semiconductor Corporation
FAN8408D
Block Diagram
OUT
B
1
3
LD
2
Commutation &
Control
& TSD
HO
OUT
A
7
V
CC
GND
4
5
6
IN+
IN-
8
Pin Definitions
Pin Number
1
2
3
4
5
6
7
8
Pin Name
OUT
B
HO
LD
V
CC
IN+
IN−
OUT
A
GND
I/O
O
O
-
-
I
I
O
-
Pin Function Description
Motor output B
Hall output
Triangle pulse generator for lock detector
and automatic restart
Supply voltage
Hall input +
Hall input
−
Motor output A
Ground
Remark
-
Open Collector
-
-
-
-
-
-
2
FAN8408D
Equivalent Circuits
Description
OUT
B
OUT
A
Pin No.
1
7
1
7
Commutation
Internal Circuit
HO
2
2
Commutation
LD
3
3
Lock detector
& Automatic
restart
Commutation
V
LDCP
V
LDCL
IN+
IN-
5
6
5
6
Commutation
3
FAN8408D
Absolute Maximum Ratings (Ta = 25°C)
Parameter
Maximum power supply voltage
Maximum power dissipation
Thermal
resistance
note1
note1
Symbol
V
CCMAX
P
DMAX
Θ
JA
V
OMAX
I
OMAX
I
HO
V
HO
V
HACMAX
T
OPR
T
STG
Value
18
429
note2
620
note3
291.61
note2
201.52
note3
30
1.2
note4
10
36
6
−25
~ 85
−55
~ 150
Unit
V
mW
°C/W
V
A
mA
V
V
°C
°C
Maximum output voltage
Maximum output current
Hall output current
Hall output withstanding voltage
Maximum hall input ac level
Operating temperature
Storage temperature
Note1:
PCB Condition: Thickness(1.6mm), Dimension(76.2mm * 114.3mm)
Refer: EIA/J SED 51-3 & EIA/J SED 51-7
Note2:
Air condition (0m/s)
Note3:
Air condition (3m/s)
Note4:
Should not exceed P
D
or ASO value
Power Dissipation Curve (Air condition = 0m/s)
0.5
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
0
20
40
60
80
Tc or Ta[°C]
100
120
140
160
4
Pd[W]
FAN8408D
Air Speed &
Θ
JA
350
300
JA[°C/W]
250
200
150
100
50
0
0
1
2
3
Air Speed[m/s]
4
5
6
Recommended Operating Conditions (Ta = 25°C)
Parameter
Function compensation operating voltage
Symbol
V
CC
Min.
4.0
Typ.
−
Max.
15.0
Unit
V
Electrical Characteristics
(Ta=25°C, V
CC
=12V unless otherwise specified)
Parameter
Supply current
Lock detector charging current
Lock detector discharging current
Lock detector charging/discharging ratio
Lock detector capacitor clamp voltage
Lock detector capacitor comparator voltage
Output low level voltage
Output leakage current
Output zener voltage
Hall output pin low level voltage
Hall output pin leakage current
Hall input dc range
Hall input offset
Symbol
I
CC
I
LDC
I
LDD
R
CD
V
LDCL
V
LDCP
V
OL
I
OL
V
OZ
V
HLL
I
HLL
V
HDC
V
HOF
I
O
=10mA
-
-
V
REF
=6V
I
O
=200mA
-
Clamp current=10mA
Conditions
When output is off.
V
LD
=1.8V
V
LD
=1.8V
R
CD
=I
LDC
/I
LDD
-
-
Min.
-
2.38
0.48
3.0
2.4
0.7
-
-
28
-
-
1
-10
Typ.
-
3.40
0.68
5.0
2.85
0.99
0.9
0
30
0.2
0
-
-
Max.
3.0
4.42
0.88
7.0
3.3
1.2
1.2
10
32
0.5
10
V
CC
-
2V
10
Unit
mA
µA
µA
−
V
V
V
µA
V
V
µA
V
mV
5