NJU7333
Single-phaseDC Brushless Motor Driver IC
s
GENERAL DESCRIPTION
s
PACKAGE OUTLINE
The NJU7333 is a single-phase DC brushless motor
driver IC for small fan-motor and high power applications. It
features MOS-FET driver circuit for better saturation
characteristics. Slew late of amplifiers and feedback
resistors are optimized to achieve low-noise motor
operation. Maximum output current is 500mA. The
NJU7333 includes. frequency generator (FG) output, lock
detect (with auto recovery circuit) ,and a thermal shutdown
circuit .
NJU7333R
s
FEATURES
•
Operating Voltage V
DD
=2.4
∼
5.5V
•
FG Output
•
Internal Lock Detect / Auto Recovery Circuit
•
Internal Thermal Shutdown Circuit
•
Low Operating Current I
DD
=3mA (Typ.)
•
Low Saturation Output Voltage
Vsat=±0.35V @Io=±500mA
•
C-MOS Technology
•
Package Outline
VSP10
s
BLOCK DIAGLAM
s
PIN FUNCTION
1:Ct
2: FG
3: Vdd
4: OUT B
5: Vss
6: Vss
7: OUT A
8: Vdd
9: IN-
10: IN+
-1-
NJU7333
Preliminary
s
ABSOLUTE MAXIMUM RATINGS
PARAMETER
Supply Voltage
Input Voltage
Output Current (Peak)
Operating Temperature Range
Storage Temperature Range
Power Dissipation
RATINGS
+7.0
-0.3
∼
V
DD
+0.3
1.0
-40
∼
+85
-50
∼
+150
400
SYMBOL (unit)
V
DD
(V)
V
ID
(V)
I
O PEAK
(A)
Topr (°C)
Tstg (°C)
P
D
(mW)
(Ta=25°C)
NOTE
Device itself
s
RECOMMENDED OPERATING CONDITIONS
PARAMETER
SYMBOL
Supply Voltage
Operating Temperature Range
Input Common Mode Voltage
Range
Output Current
V
DD
Tj
V
ICM
Io
CONDITION
-
-
-
-
MIN.
2.4
-40
0.4
-
(V
DD
=5V, Ta=25°C)
TYP.
MAX. UNIT
5.0
5.5
V
-
-
-
85
4.0
0.5
°C
V
A
-2-
NJU7333
Preliminary
s
ELECTRICAL CHARACTERISTICS
PARAMETER
SYMBOL
General
Operating Current
Thermal Shutdown
Temperature
Thermal Shutdown
Hysteresis
Hall Amplifier
Input Offset Voltage
Feedback Resistance
Open loop gain
CONDITION
-
-
-
MIN.
-
-
-
(V
DD
=5V, Ta=25°C)
TYP.
MAX.
UNIT
3.0
180
50
4.0
-
-
mA
°C
°C
I
DD
T
TSD
T
HYS
V
IO
R
F
A
V
V
ICM
-
-
-
-
-7
22.0
-
0.4∼4.0
-
27.5
80
-
7
33.0
-
-
mV
kΩ
dB
V
Input Common Mode
Voltage Range
Outputs
Maximum Output
Voltage Range
Output Resistance
FG L Output Voltage
FG H Leak Current
Lock Detect Circuits
Lock Protect
Operating Voltage
Lock Detect
Discharge Current
Lock Detect
Discharge Current
Clamp Voltage
Detect Voltage
V
OH
V
OL
R
ONH
R
ONL
V
FG
I
FG - LEAK
Io=+350mA
Io= -350mA
Io=+500mA
Io= -500mA
4pin=5V,3pin=0V, R
P
=10kΩ
4pin=0V,3pin=5V, R
P
=10kΩ
4.65
-
-
-
-
-
4.75
0.25
0.5
0.5
-
-
-
V
0.35
-
-
0.3
1.0
Ω
V
µA
V
LOP
I
DCHG
I
DCHG
V
CL
V
ID
-
-
-
-
-
4.0
-
-
-
-
-
1.5
0.5
2.6
0.6
-
-
-
-
-
V
µA
µA
V
V
-3-
NJU7333
Preliminary
s
APPLICATION NOTE
The NJU7333 is a single-phase DC brushless motor driver IC featuring CMOS process.
It is suitable for fan motor drivers for a small equipment such as the note personal computers.
[Application Circuit Example]
V+
D1
GND
R3
R1
V
DD
Hall
element
IN+
IN-
R2
Ct
C2
V
SS
FG
FG out
OUTB
OUTA
Motor
C1
NJU7333
[Design Notes]
Above application example is designed for 5V operation with motor current of 500mA. It uses the following
components:
Hall Elements: HW101A (AKE)
1. Selection of C1 and D1:
C1 is used for a noise reduction purpose. A typical value is 0.1uF.
Optimize the value in actual operating conditions if necessary. D1 is a diode for protection against reverse voltage
supply. Silicon rectifier diode (WO3C, 10D1 and equivalent) is appropriate.
2. Lock Protection Function (Design of C2 value):
Lock Protection Function, consists of Motor Lock Detection and Auto Resume Function, is a safety feature to protect
a motor and a driver circuit from fatal destruction in case of motor halt.
Motor Lock Detection detects motor halt due to irregular load conditions and then cuts motor driving current f or
safety operation. A value of C2 determines Lock detection time (T
on
) and Auto Resume Time (Toff).
-4-
NJU7333
Preliminary
Lock detection time (Ton) is given by:
T
ON
=
C
2
V
CL
−
V
ID
[
sec
]
I
CHG
Where C2 is 0.47uF:
T
ON
=
0.47
×
10
−
6
×
2 .6
−
0 . 6
=
0.62
[
sec
]
1.5
×
10
−
6
Auto Resume Time (Toff) is given by:
T
OFF
=
C
2
V
CL
−
V
ID
[
sec
]
I
DCHG
Where C2 is 0.47uF:
T
OFF
=
0.47
×
10
−
6
×
2.6
−
0.6
=
1.88
[
sec
]
0.5
×
10
−
6
In actual application, Lock detection time (Ton) is affected by the mechanical time constant of a motor. Therefore,
constant start up must be confirmed in actual evaluation taking operating variations (i.e.Temperature, Voltage change
and so on) in consideration.
A typical value of C2 is either 0.47uF or 1uF depending on a motor.
Hall input
Motor output
Ct Terminal voltage
Toff
Ton
Motor Lock protection period
Motor Locked
Returns to normal
operation
3. Design of hall element bias resistance (R1
and R2)
Hall amplifier is a differential amplifier with hysteresis characteristics (24mV typical).
The common-mode input voltage is between 0.4V and V
DD
-1V and the input signal must be within the
range.Non-excitation hall bias voltage is to be set at a half of V
DD
for effective use of common-mode input voltage
range. Therefore the same value of hall bias resistors is selected for R1 and R2.
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