ROHM BA6901F

BA6901F
Motor driver ICs
2-Phase half-wave motor pre driver for
fan motor
BA6901F
BA6901F is a 2-phase half-wave motor pre driver for fan motors. This IC has lock detection, and automatic restart
functions as motor protection function.
Variable speed control is possible by charge-discharge pulse circuit and PWM input. This IC incorporates current limit
circuit, hall signal output pin, and alarm signal output pin.
!Applications
Fan motors
!Features
1) Lock detection, automatic restart circuit.
2) Hall signal output.
3) Alarm signal output.
4) Current limit circuit.
5) PWM control (PWM pulse signal input).
6) Charge-discharge pulse circuit (Possible to control of variable speed by charge-discharge pulse circuit and PWM input).
7) Thermal shut down circuit.
!Absolute maximum ratings (Ta = 25°C)
Parameter
Symbol
Limits
Power supply voltage
VCC
36
Power dissipation
Pd
625
Unit
V
∗1
mW
°C
Operating temperature
Topr
−25~+75
Storage temperature
Tstg
−55~+150
°C
Output current
IOUT
70
∗2
mA
Signal output voltage
VSO
36
V
Signal output current
ISO
15
mA
Junction temperature
Tjmax
150
°C
∗1 To use at temperature above 25°C reduce 5.0mW / °C.
(On 70.0mm×70.0mm×1.6mm glass epoxy board.)
∗2 This value is not to be over Pd and ASO.
!Recommended operating conditions (Ta = 25°C)
Parameter
Symbol
Min.
Typ.
Max.
Unit
Operating supply voltage
VCC
3.5
−
28.0
V
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BA6901F
Motor driver ICs
!Block diagram
CR
1
HO
2
+
16
TOUT
15
VCC
A2
14
A2
A1
13
A1
12
CL
11
CS
10
H−
9
H+
−
REG
3
LOCK
DETECTION
&
ALB
4
PWM
5
LD
6
LOGIC
AL
AUTOMATIC
RESTART
PWM
−
+
+
−
7
−
CNF
+
+
−
GND
8
!Pin descriptions
Pin No. Pin name
Function
1
CR
Connection terminal of capacitor and resistor for charge-discharge pulse circuit
2
HO
Hall signal output terminal
3
AL
Alarm output terminal
4
ALB
Alarm output terminal (Reverse signal output of AL)
5
PWM
PWM input terminal (H,OPEN : output ON, L : output OFF)
6
LD
Connection terminal of capacitor for Lock detection, Auto restart
7
CNF
Connection terminal of capacitor for phase compensation
8
GND
GROUND terminal
9
H+
Hall signal input terminal
10
H−
Hall signal input terminal
11
CS
Current sence input terminal
12
CL
Current limit input terminal
13
A1
Output terminal
14
A2
Output terminal
15
VCC
Power supply terminal
16
TOUT
Charge-discharge pulse output terminal
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BA6901F
Motor driver ICs
!Input / output truth circuit
Hall input
VCC
H+
H−
Current limit input
PWM input
VCC
VCC
VREG
1.42V
(Typ.)
30kΩ
(Typ.)
6.75kΩ
(Typ.)
PWM
20kΩ
(Typ.)
CS
CL
Output
Charge-discharge pulse output
VCC
VCC
A1,A2
TOUT
Signal output
HO,AL,ALB
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BA6901F
Motor driver ICs
!Electrical characteristics (unless otherwise noted, Ta = 25°C, VCC = 12V)
Parameter
Symbol
Min.
Typ.
Max.
Unit
Conditions
ICC
3.0
7.0
12.0
mA
Hall input hysteresis
Vhys
±4
±10
±20
mV
VCOM=6.0V
Charge current of capacitor for lock detection
ILDC
2.0
5.0
8.0
µA
VLD=1.5V
Discharge current of capacitor for lock detection
ILDD
0.2
0.5
0.8
µA
VLD=1.5V
Circuit current
rCD
4
10
16
−
Clamp voltage of capacitor for lock detection
VLDCL
1.60
2.40
3.20
V
Comparison voltage of capacitor for lock detection
Charge-discharge current ratio of capacitor for lock detection
At output : OFF
rCD=ILDC / ILDD
VLDCP
0.25
0.60
0.95
V
Output H voltage
VOH
−
1.5
2.0
V
IO=−10mA vs. VCC voltage
Hall signal outputn L voltage
VHO
−
0.10
0.50
V
IHO=5mA
IAL=5mA, AL, ALB terminal
VAL
−
0.10
0.50
V
VofsCS
75.0
92.0
99.5
mV
TCS
−
50
150
µsec
PWM input voltage H
VPWMH
2.0
−
−
V
At output : ON
PWM input voltage L
VPWML
−
−
0.8
V
At output : OFF
Charge-discharge pulse comparison voltage
VCRCP
0.26
0.35
0.44
V
Charge-discharge pulse output voltage H
VTOH
0.7
1.0
1.3
V
ITO=−0.5mA vs. VCC voltage
Charge-discharge pulse output voltage L
VTOL
0.7
1.0
1.3
V
ITO=0.5mA
Alarm output L voltage
CL-CS offset voltage
Response time for current limit
CL=100mV
This product isn't designed for protection against radioactive rays.
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BA6901F
Motor driver ICs
!Circuit operation
•Lock detect circuit, automatic restart circuit
Charge and discharge time at motor lock condition varies with the value of external capacitor at LD terminal, and is
given by the following equation.
=
C × (VLDCL−VLDCP)
ILDC
Toff (Discharge time) =
C × (VLDCL−VLDCP)
ILDD
Ton (Charge time)
C
VLDCL
VLDCP
ILDC
ILDD
:
:
:
:
:
Value of capacitor at LD terminal
(2.40V
Typ.)
Comparison voltage of capacitor (0.60V
(5.0µA
Charge current of capacitor
Typ.)
(0.5µA
Typ.)
Clamp voltage of capacitor
Discharge current of capacitor
Typ.)
The following value shows charge time and discharge time at C=1.0µF for reference.
Charge time=0.36sec.
(Output : ON)
Discharge time=3.60sec.
(Output : OFF)
Shows timing chart of LD terminal.
H+
A1
Toff
Ton
Output Tr. OFF
ON
VLDCL
LD
VLDCP
HIGH(Open collector)
AL
LOW
ALB
HO
Depend on the hall output
Motor lock
Detect lock
Lock cancel
Reset ordinary motion
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BA6901F
Motor driver ICs
•CL, CS, CNF terminal
Output current is limited by voltage (VCL) that inputting to the CL terminal.
Resistor (RNF) of the output current detection is connected between emitter of the external output transistor and GND,
and output current is detected by inputting the voltage which occurred in that resistor to the CS terminal. Output current
is restricted as the electric potentials of the CL and the CS terminals are equal. But, there is offset between the CL
terminal and the CS terminal. Value of current limit is found by the following equation.
Value of current limit =
VCL−VCL_CSofs
RNF
VCL_CSofs : Offset between CL terminal and CS terminal
This offset is not the one written at electrical characteristics table, but the value determined under condition that the
external output transistors are connected. Be careful of this value, because it varies according to the external transistor.
The lager hFE of the output transistor makes the offset smaller, and smaller hFE makes it larger.
For output current limitation, a capacitor for the phase compensation between the CNF terminal and the VCC terminal is
needed.
However, when an output current limit isn’t needed, CS terminal is fixed on the low level (GND), and CL terminal is fixed
on the high level (VCC), and the capacitor of the CNF terminal isn’t necessary.
CNF
VCC
CNF
VCC
A1
A1
A2
A2
CS
CS
CL
Current limit
(a) In the case that the current limit is applied.
CL
(b) In the case that the current limit isn't applied.
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BA6901F
Motor driver ICs
•CR, TOUT terminal
By connecting the external capacitor and resistor to the CR terminal, the saw tooth wave is produced by the chargedischarge of the capacitor which are corresponding to the cycle of the hall signal.
The saw tooth wave of CR terminal varies with the external capacitor and resistor.
The waveform of the CR terminal passes through the buffer amplifier and is outputted to TOUT terminal.
The input voltage range of the CR terminal for the buffer amplifier of TOUT is 0.26V∼VCC.
In case that the signal of the CR terminal is out of the range, outputted TOUT signal is not the same as the CR signal.
And, the voltage range of the TOUT terminal waveform is different from the CR terminal.
CR : VCRCP (0.35V ; Typ.) ∼ VCC
TOUT : VTOUTL (1.0V ; Typ.) ∼ VCC − VTOUTH (1.0V ; Typ.)
Hall input
Hall input
VCC-VTOUTH
CR
CR
VCRCP
VCRCP
VCC-VTOUTH
TOUT
VTOUTL
In case that the CR waveform dose not
exceed the VCC-VTOUTH.
TOUT
VTOUTL
In case that the CR waveform exceeds
the VCC-VTOUTH.
Timing chart for CR terminal, TOUT terminal
•PWM terminal
If the signal inputted to the PWM terminal is L (less than 0.8V), output (A1, A2) is forced to be turned off. For the normal
operation of output (A1, A2), PWM signal is needed to be H (more than 2.0V).
In case that PWM terminal is open, outputs are in the normal operation mode, because the PWM terminal is pulled up
with resistor (30kΩ : Typ. ) in the IC.
The application circuit example that changes the rotation speed of fan motor dependent on ambient temperature by
using charge-discharge pulse circuit, PWM input and the thermistor is shown below.
+
−
Current
limit
Thermistor
H
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BA6901F
Motor driver ICs
!Application example
CR
TOUT
+
1
16
−
HO
VCC
15
2
REG
AL
A2
LOCK
DETECTION
ALB
&
4
LOGIC
3
AUTOMATIC
RESTART
A2
14
A1
13
A1
CL
PWM
PWM
5
12
−
+
LD
+
6
CS
11
−
CNF
H−
7
10
−
+
+
GND
−
8
H+
HALL
9
Output terminal
voltage at ON side
!Operation notes
1) Thermal shut down (TSD)
This IC is built-in TSD.
TSD has the temperature hysteresis.
TSD ON (Typ. : 175°C)
All output transistor OFF.
TSD OFF
155
TSD ON
TSD OFF
Reset ordinary motion.
(It has the temperature hysteresis
of 20°C <Typ.> )
175
Junction temperature (°C)
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BA6901F
Motor driver ICs
2) Power dissipation
Power consumption (PC) of BA6901F is calculated to the following equation.
Pc = Pc1 + Pc2 + Pc3
(1) Pc1 : Power consumption by circuit current
Pc1 = VCC × ICC
(2) Pc2 : Power consumption of output terminal
Pc2 = (VCC – VOH ) × Io
VOH is H voltage of output (A1 or A2).
Io can be decreased by using the transistor of high hFE rank and it is effective to consumption
electric power reduction.
(3) Pc3 : Power consumption of HO, AL and ALB terminal
Pc3 = VHO × IHO + VAL × IAL + VALB × IALB
VHO is L voltage of Hall signal output (HO).
VAL and VALB are L voltage of lock detection output (AL or ALB).
IHO, IAL and IALB are current of HO, AL or ALB.
Please care to the terminal design not to exceed the allowable power dissipation.
3) Hall signal input terminal (H+, H−)
VCC
H−
H+
VCC
VCC-2.8V
Hall input voltage range
C2
R1
1/2VCC
RH
C1
Hall element
R2
GND
Hall Amp input bias voltage
Hall Amp input current =
VCC
R1 + R2 + RH
Hall amp of BA6901F has input hysteresis
(±10mV : Typ.)
RH : Impedance of Hall element
Please adjust hall Amp input bias voltage by value of R1, R2 so that hall signal contains amplitude, input within range
0V∼ (VCC−2.8V).
In case VCC noise influence the hall signal by board wiring pattern, please connect capacitor C1 like above figure.
In the case of long board wiring pattern from hall element to hall signal input terminal, please connect capacitor C2 like
above figure.
4) GND
Please keep up the voltage of GND less than the voltage of another terminal surely.
5) This product is produced with strict quality control, but destroyed in using beyond absolute maximum ratings.
Once IC destroyed, a failure mode cannot be defined (like short-mode or open-mode). Therefore, physical security
counter measure, like fuse, is to be given when a specific mode to be beyond absolute maximum ratings is
considered.
9/10
BA6901F
Motor driver ICs
1200
12
1000
10
12.0
800
625
600
400
200
0
0
25
50
75
100
125
8
6
4
2
0
150
SATURATION VOLTAGE : VOH (V)
11.8
CIRCUIT CURRENT : ICC (mA)
POWER DISSIPATION : Pd (mW)
!Electrical characteristic curves
0
5
10
15
20
25
SUPPLY VOLTAGE : VCC (V)
AMBIENT TEMPERATURE : Ta (°C)
Supply current−Supply voltage
characteristic
Power dissipation
30
11.6
11.4
11.2
11.0
10.8
10.6
10.4
10.2
10.0
0
10 20 30 40 50 60 70 80 90 100
OUTPUT CURRENT : IO (mA)
Output "H" voltae−Output current
characteristic
!External dimensions (Units : mm)
1
8
0.3Min.
9
4.4±0.2
0.11
1.5±0.1
6.2±0.3
10.0±0.2
16
1.27
0.15±0.1
0.1
0.4±0.1
SOP16
10/10