SANKEN SI

5-phase Stepper Motor Star Connection Unipolar Driver IC
SI-7500A
■ Ratings
(Ta = 25°C)
Absolute
maximum
rating
Supply voltage
Output
current
(A)
(V)
Junction
temperature
(°C)
Operating
ambient
temperature (°C)
Storage
temperature
(°C)
Type No.
VCC
Vb
Io
Tj
Top
Tstg
SI-7500A
40
8
1.2
+125
–20 to +80
–30 to +100
■ Characteristics
Electrical
characteristics
Operating supply voltage
Type No.
Vb input
External
*Input voltage
*Input
current zener diode
current
breakdown
voltage
(V)
(mA/ø)
(%)
(mA)
(V)
(V)
(mA)
VCC
Vb
IO
I OPD/IO
Ib
VZ
V IH1 V IH2 VIL IIH1 I IH2
min typ max min typ max min typ max min typ max
max
min max max max max max max
SI-7500A
17
24
30
4.5
5
Output current
Power down
Ratio
5.5 200 750 1000 35
50 100
VCC
x1.5
15
50
3.9
1.3
0.6
0.21 0.22
Zener diode for
canceling counter EMF
Auxiliary power supply Vb
ZD
Variable current
resistor
Reference
voltage
Rx
Comparator
amplifier
M
Current
controller
Trigger pulse
generator
circuit
Excitation signal
amplifier
Excitation signal
2-3 phase excitation
Trigger
pulse
time
(V)
Vtrig
min max
(µs)
Ttrig
min typ
(kHz)
Ftrig
typ max
4.0
1.0
20
Vb
2.0
25
* Input voltage and input current
conditions
VIH1 : Vb = 5V, Q1 to Q5ON
RX = , I IN = 0.2mA
VIH2 : Vb = 5V, Q1 to Q5OFF,
IIN = 0.22mA
IIH1 : Vb = 5V, Q1 to Q5ON,
VIN = 3.7V
IIH2 : Vb = 5V, Q1 to Q5OFF,
VIN = 0.9V
■ Block diagram
Main power
supply VCC
(Ta = 25°C)
Trigger
pulse
frequency
Trigger
pulse
voltage
Counter EMF
Canceller
SI-7500A
Current detection
resistor Rs
■ Equivalent circuit diagram
w
ri
t
o
!2 !5
!3
!6
!9
q
@0
Q6
Q7
R36
R1 R6
D1 Q11
D11
D6
u
R7
R41
Q1
R47
R2
D12
D13
D7
D8
R3
R16
R17
R32
R39
R8
R43
R44
Q2
Q3
R28
D14
D15
R18
R19
R10
D5 Q15
D9 D10
R15
Q4
R40
R5
R14
R23
R27
Q10
R9 R4
Q14 D4
R13
R22
R31
Q9
R38
D3 Q13
R12
R21
R26
Q8
Q12 D2
R42
MIC1
R11
R46
R37
R45
MIC3
Q5
R20
R24
R34
R25
R29
R30
R35
!8
e
y
!0
!1
!4
!7
43
SI-7500A
■ Diagram of external circuits
SI-7500A
5-phase stepper motor
VCC
+
100 µ F
50V
ZD
9
13
16
OUT-5
OUT-4
5
OUT-3
Vb
2
OUT-2
VCC
VR
44kΩ
ZD
7
Vb
20
OUT-1
1
IN-2
1kΩ
4
8
7
2
1S1555
IN-3
IN-4
Vief.
IN-5
4
8
Excitation signal
input (Active High)
2-3 phase excitation
12
15
19
RS5
RS4
RS3
11
RS2
RX
0.01µF
RS1
1kΩ
18
GND
1000pF
3
1
6
5
SI-7500A
2SA561
3.9kΩ
555
VR
300Ω
IN-1
3
6
10
14
17
RS1
RS2
RS3
RS4
RS5
RS1 to RS5 : Current detection resistor
RX : Variable current resistor
Power down signal input
(Active high)
■ External dimensions
(Unit: mm)
■ Supply voltage vs. Output current
Plastic package
3.5
3.8
8.0 φ
8.6±1
3.4
1.8
35.0±0.5
Type No.
Lot No.
3
0.5
P=2.54
Pin No.
Rx = ∞
1.2
Output current Io (A)
7.0±0.5
63.0±0.4
16.6
69.0±0.5
(Typical value,
Motor : PH566-B
Rs = 1Ω
Vb = 5.0V
2kΩ
1.0
1kΩ
0.8
510Ω
0.6
200Ω
100Ω
0.4
0.2
1.4
12....................................20
0
0
20
24
30
Supply voltage VCC (V)
■ Case temperature vs. Output current
■ Torque characteristics
1.0
0.8
0.6
0.4
0.2
0
0
25
50
75
Case temperature Tc (°C)
44
2.5
Pull-out torque τOUT (kg-cm)
Output current Io (A)
(Typical value)
VCC=24V
Motor : PH566-B
100
2.0
1.5
Supply voltage VCC = 24V
Vb = 5V
Output current Io = 0.8 A/phase (fixed)
Counter EMF canceler Zener diode Vz = 49V
Motor : PH566B
1.0
0.5
0
0
0.1
0.2
0.5
1
2
Response frequency f (kpps)
5
10
20
SI-7500A
Application Note
■ Determining the output current IO (motor coil current)
The main elements that determine the output current are
Current detection resistor Rs, Supply voltage Vb, and Variable current resistor RX.
Fig. A
IOH
(1) Normal mode
To operate a motor at maximum current level, set RX to
infinity (open).
From Fig. A, when the maximum output current ripple is
designated as IOH, its value will be,
VRSH
IOH =
....................................................... [A]
RS
Waveform of output current
Fig. B
1.4
V RSH can be computed as follows:
V)
VRSH Max. (Vb = 5.0
1.2
VRSH = 0.2 Vb + 0.213 (center value) .............. [B]
The relationship between I OH and RS is shown in Fig. B.
VRSH (V)
From equations [A] and [B], the output current I OH can
be computed as follows:
I
(0.2 Vb + 0.213)
IOH =
RS
1.0
VRSH Min. (Vb = 5.0V)
0.8
Vb + 0.1
VRSH(max) = 4.69 + 1.92 + 0.2 (V)
Rx
Vb + 0.09
VRSH(min) = 5.25 + 2.06 + 0.15 (V)
Rx
0.6
0.4
(Rx : kΩ)
0.2
(2) Power down mode
When an external resistor RX is connected, VRSH changes
as shown in the Fig. B even when RS is retained. Obtain
the power down output current I OHPD from Fig. B and
equation [A].
0
0
1
2
3
4
∞
External resistor Rx (kΩ)
■ Thermal design
Obtain the internal power dissipation that corresponds to the output current to be required from Fig. C, multiply this by three,
and determine the size of the heatsink from the derating curve in Fig. D. The derating curve is based on junction
temperature of 125°C. However, make some allowance so that Tc is 85°C or less and then select the proper heatsink size.
Fig. C SI-7500A Internal power dissipation per phase PD
vs. Output current IO
Fig. D SI-7500A Derating curve
6
Motor : PH566-B
Vb = 5V
Holding mode
150 × 100
Heatsink : Aluminum
Thickness : 2 mm
100 × 100
5
Power dissipation PD (W)
Power dissipation per phase Pdiss/φ (W)
20
(Typical
value)
4
3
VCC = 30V
24V
20V
2
15
50 × 100
10
Without
heatsink
5
1
0
0
0.2
0.4
0.6
0.8
Output current lo (A)
1.0
1.2
0
0
20
40
60
80
Ambient temperature Ta (°C)
45
SI-7200M, SI-7230M, SI-7115B, SI-7300A,
SI-7330A, SI-7500A and SI-7502
Handling Precautions
(Note: The SI-7502 is applicable for item (2) only.)
For details, refer to the relevant product specifications.
(1) Tightening torque:
The torque to be applied in tightening screws when mounting the IC on a
heatsink should be below 49N•m.
(2) Solvent:
Do not use the following solvents:
Substances that
Chlorine-based solvents
: Trichloroethylene,
dissolve the package
Trichloroethane, etc.
Aromatic hydrogen compounds : Benzene, Toluene,
Xylene, etc.
Ketone and Acetone group solvents
Substances that
weaken the package
Gasoline, Benzine and Kerosene
(3) Silicone grease:
The silicone grease to be used between the aluminum base plate of the hybrid
IC and the heatsink should be any of the following:
• G-746
SHINETSU CHEMICAL INDUSTRIES CO., LTD.
• YG6260
TOSHIBA SILICONE CO., LTD.
• SC102
DOW CORNING TORAY SILICONE CO., LTD.
Please pay sufficient attention in selecting silicone grease since oil in some
grease may penetrate the product, which will result in an extremely short
product life.
Others
• Resistance against radiation
Resistance against radiation was not considered in the development of these ICs
because it is assumed that they will be used in ordinary environment.
54