NJU7343 Single-phase DC Brushless Motor Driver IC

NJU7343
Single-phase DC Brushless Motor Driver IC
■ GENERAL DESCRIPTION
■ PACKAGE OUTLINE
The NJU7343 is single-phase DC brushless motor driver
IC designed for a small fan motor. Adopting the CMOS
process, it can provide a low saturation output voltage that
is effective in high current operation.
It has Lock Detect / Auto Reset and Thermal Shutdown
NJU7343R
Circuit for safety fan operation, and it has FG output
( MSOP10 (VSP10) )
function as useful function.
It is available in a small MSOP10 (VSP10) package, which
makes motors thin and small. It is suitable for small and
high output fan motor applications.
■ FEATURES
• Operating Voltage
2.2 to 5.5V
• Lock Detect / Auto Release
• FG Output
• Thermal Shutdown Circuit
• Low Operating Current
• Low Saturation Output Voltage
• Vsat= ±0.25V @Io=±500mA
• Input offset voltage
±5mV
• CMOS Technology
• Package Outline
MSOP10 (VSP10)*
*MEET JEDEC MO-187-DA
■ BLOCK DIAGRAM
■ PIN FUNCTION
1
10
LD
2
9
3
8
4
7
TSD
5
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6
1: Ct
2: FG
3: VDD
4: OUT B
5: Vss
6: Vss
7: OUT A
8: VDD
9: IN10: IN+
(Note)
All VDD pins should be connected to the power
supply and all VSS pins should be connected to
the ground respectively. Otherwise, the electrical
characteristics may not satisfy specifications
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NJU7343
■ ABSOLUTE MAXIMUM RATINGS
PARAMETER
Supply Voltage
Input Voltage
Output Current (Peak)
Operating Temperature Range
Junction Temperature Range
Storage Temperature Range
Power Dissipation
RATINGS
SYMBOL (unit)
+7.0
-0.3 ∼ VDD+0.3
1000
-40 ∼ +85
-40 ∼+150
-40 ∼+150
400
VDD (V)
VID(V)
IO PEAK (mA)
Topr (°C)
Toj (°C)
Tstg (°C)
PD (mW)
■ RECOMMENDED OPERATING CONDITIONS
PARAMETER
SYMBOL
CONDITION
Supply Voltage
(Ta=25°C)
NOTE
Device itself
MIN.
TYP.
(VDD =5V, Ta=25°C)
MAX.
UNIT
VDD
Ct=0V
2.2
5.0
5.5
V
Junction Temperature
Range
Input Common Mode
Voltage Range
Tj
-
-40
-
125
°C
VICM
-
0.4
-
4.0
V
Output Current
IO
-
-
-
500
mA
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Ver.2013-09-09
NJU7343
■ ELECTRICAL CHARACTERISTICS
PARAMETER
SYMBOL
(VDD =5V, Ta=25°C)
TYP.
MAX.
UNIT
CONDITION
MIN.
IDD
-
-
3.0
4.0
mA
TTSD
-
-
180
-
°C
THYS
-
-
50
-
°C
Input Offset Voltage
VIO
-
-5
-
5
mV
Feedback Resistance
RF
-
22.0
27.5
33.0
kΩ
Open Loop Gain
AV
-
-
80
-
dB
Input Common Mode
Voltage Range
VICM
-
0.4 to 4.0
-
-
V
VOH
Io=+350mA
4.65
4.75
-
VOL
Io=-350mA
-
0.25
0.35
RONH
Io=+500mA
-
0.5
-
RONL
Io=-500mA
-
0.5
-
ICHG
-
-
0.6
-
µA
IDCHG
-
-
0.1
-
µA
Clamp Voltage
VCL
-
-
2.8
-
V
Detect Voltage
VID
-
-
0.8
-
V
FG L Output Voltage
VFG
IN+(10pin)=0V,IN-(9pin)=5V, RP=10kΩ
−
−
0.3
V
FG H Leak Current
IFG-LEAK
IN+(10pin)=5V,IN-(9pin)=0V, RP=10kΩ
−
−
1.0
μA
General
Operating Current
Thermal Shutdown
Temperature
Thermal Shutdown
Hysteresis
Hall Amplifier
Motor Output
Maximum Output
Voltage Range
Output Resistance
Lock Detect Circuit
Lock Detect
Charge Current
Lock Detect
Discharge Current
V
Ω
Rotation Detect Output
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NJU7343
■ APPLICATION NOTE
The NJU7343 is single-phase DC brushless motor driver ICs in a small MSOP10 (VSP10) package.
With minimal external components, that can drive up to 500mA of motor current for small fan application.
[Application Circuit Example]
V+
D1
C1
GND
R3
R1
VDD
Hall
element
OUTA
IN+
IN-
Motor
R2
Ct
OUTB
NJU7343
C2
VSS
FG
[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 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 (Ton) and Auto Resume Time (Toff).
Lock detection time (Ton) is given by:
TON = C 2
-4-
VCL − VID
[sec]
Ich
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NJU7343
Where C2 is 0.15uF:
TON = 0.15 × 10 −6 ×
2 .8 − 0 .8
= 0.49[sec ]
0.6 × 10 −6
Auto Resume Time (Toff) is given by:
TOFF = C 2
VCL − VID
[sec]
Idis
Where C2 is 0.15uF:
TOFF = 0.15 × 10 −6 ×
2 .8 − 0 . 8
= 3.00[sec ]
0.1 × 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 from 0.1uF to 0.47uF depending on a motor.
Hall input
Motor output
VCL
Ct Terminal voltage
Toff
Ton
Motor Lock protection period
Motor Loxked
Returns to normal operation
*Remarks : When VDD becomes lower than 4V,the Clamp Voltage(VCL ) becomes lower
accordingly. This makes Ton and Toff shorter and may cause issues associated with
the restarting of the motor from the lock protection state.Therefore, careful
evaluation is necessary with actual motors.
3. Design of hall element bias resistance (R1 and R2)
Hall amplifier is a differential amplifier.
The common-mode input voltage is between 0.4V and VDD-1V and the input signal must be within the range.
Non-excitation hall bias voltage is to be set at a half of VDD for effective use of common-mode input voltage range.
Therefore the same value of hall bias resistors is selected for R1 and R2.
Given that the bias current is set to be 5mA by HW101A datasheet, R1 and R2 can be determined as follows:
R1 + R 2 + Rin =
5
VDD
=
= 1 . 0 kΩ
Ihbias 5 × 10 −3
R1 = R 2 = 300 Ω
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NJU7343
The output voltage of hall elements is influenced by the bias current and magnetic flux density of hall elements.
The optimum input voltage of NJU7343 is 100mVp-p and higher. With such input voltage, the highest efficiency can
be obtained.
4. Design of FG output resistance (R3)
FG Out (FG: Pin2) is an open drain output and R3 is a pull up register. A typical value of R3 is 10kΩ.
The timing chart is as follows.
Hall input
IN+
FG
output
[CAUTION]
The specifications on this databook are only
given for information , without any guarantee
as regards either mistakes or omissions. The
application circuits in this databook are
described only to show representative usages
of the product and not intended for the
guarantee or permission of any right including
the industrial rights.
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Ver.2013-09-09