SANYO STK672-612B-E

Ordering number : ENA2114
STK672-612B-E
Thick-Film Hybrid IC
2-phase Stepping Motor Driver
Overview
The STK672-612B-E is a hybrid IC for use as a unipolar, 2-phase stepping motor driver with PWM current control.
Applications
• Office photocopiers, printers, etc.
Features
• Built-in opened motor pin detection function (output current OFF).
• Built-in overcurrent detection function (output current OFF).
• Built-in overheat detection function (output current OFF).
• If opened motor pin, over-current, or overheat detection function is activated, the FAULT1 signal (active low) is
output. The FAULT2 signal is used to output the result of activation of protection circuit detection at 3 levels.
• Built-in power on reset function.
• The motor speed is controlled by the frequency of an external clock signal.
• 2 phase or 1-2 phase excitation switching function.
• Using either or both edges of the clock signal switching function.
• Phase is maintained even when the excitation mode is switched.
• Rotational direction switching function.
• Supports schmitt input for 2.5V high level input.
• Incorporating a current detection resistor (0.39Ω: resistor tolerance ±2%), motor current can be set using two external
resistors.
• The ENABLE pin can be used to cut output current while maintaining the excitation mode.
• With a wide current setting range, power consumption can be reduced during standby.
• No motor sound is generated during hold mode due to external excitation current control.
Any and all SANYO Semiconductor Co.,Ltd. products described or contained herein are, with regard to
"standard application", intended for the use as general electronics equipment. The products mentioned herein
shall not be intended for use for any "special application" (medical equipment whose purpose is to sustain life,
aerospace instrument, nuclear control device, burning appliances, transportation machine, traffic signal system,
safety equipment etc.) that shall require extremely high level of reliability and can directly threaten human lives
in case of failure or malfunction of the product or may cause harm to human bodies, nor shall they grant any
guarantee thereof. If you should intend to use our products for new introduction or other application different
from current conditions on the usage of automotive device, communication device, office equipment, industrial
equipment etc. , please consult with us about usage condition (temperature, operation time etc.) prior to the
intended use. If there is no consultation or inquiry before the intended use, our customer shall be solely
responsible for the use.
Specifications of any and all SANYO Semiconductor Co.,Ltd. products described or contained herein stipulate
the performance, characteristics, and functions of the described products in the independent state, and are not
guarantees of the performance, characteristics, and functions of the described products as mounted in the
customer's products or equipment. To verify symptoms and states that cannot be evaluated in an independent
device, the customer should always evaluate and test devices mounted in the customer ' s products or
equipment.
82912HKPC 018-11-0016 No. A2114-1/26
STK672-612B-E
Specifications
Absolute Maximum Ratings at Tc = 25°C
Parameter
Symbol
Conditions
Ratings
unit
Maximum supply voltage 1
VCC max
No signal
50
V
Maximum supply voltage 2
VDD max
No signal
-0.3 to +6.0
V
Input voltage
VIN max
Logic input pins
-0.3 to +6.0
V
Output current 1
IOP max
10μA, 1 pulse (resistance load)
10
A
Output current 2
IOH max
VDD=5V, CLOCK≥200Hz
1.0
A
Output current 3
IOF max
Pin16 output current
10
mA
Allowable power dissipation 1
PdMF max
With an arbitrarily large heat sink. Per MOSFET
7.3
W
Allowable power dissipation 2
PdPK max
No heat sink
2.8
W
-20 to +105
°C
150
°C
-40 to +125
°C
Operating substrate temperature
Tc
Junction temperature
Tj max
Storage temperature
Tstg
Allowable Operating Ranges at Ta=25°C
Parameter
Symbol
Conditions
Ratings
unit
Operating supply voltage 1
VCC
With signals applied
10 to 46
V
Operating supply voltage 2
VDD
With signals applied
5±5%
V
Input high voltage
VIH
Pins 10, 12, 13, 14, 15, 17 VDD=5±5%
2.5 to VDD
V
0 to 0.8
V
0.8
A
0.86
A
Input low voltage
VIL
Pins 10, 12, 13, 14, 15, 17 VDD=5±5%
Output current 1
IOH1
Tc=105°C, CLOCK≥200Hz,
Continuous operation, duty=100%
Output current 2
IOH2
Tc=80°C, CLOCK≥200Hz,
Continuous operation, duty=100%,
See the motor current (IOH) derating curve
CLOCK frequency
fCL
Minimum pulse width: at least 10μs
Recommended Vref range
Vref
Tc=105°C
0 to 50
0.14 to 1.53
kHz
V
Electrical Characteristics at Tc=25°C, VCC=24V, VDD=5.0V
Parameter
Symbol
Conditions
VDD supply current
ICCO
Pin 9 current CLOCK=GND
Output average current*
Ioave
R/L=1Ω/0.62mH in each phase
FET diode forward voltage
Vdf
If=1A (RL=23Ω)
Output saturation voltage
Vsat
RL=23Ω
Input high voltage
VIH
Pins 10, 12, 13, 14, 15, 17
Input low voltage
VIL
Pins 10, 12, 13, 14, 15, 17
FAULT1 low output voltage
VOLF
Pin 16 (IO=5mA)
5V level FAULT leakage current
IILF
Pin 16=5V
FAULT2 opened motor pin
VOF1
detection output voltage
FAULT2 Overcurrent detection
VOF2
FAULT2 Overheat detection
Pin 8 (when all protection functions have
been activated)
output voltage
VOF3
output voltage
5V level input current
IILH
GND level input current
IILL
Pins 10, 12, 13, 14, 15, 17=GND
Vref input bias current
IIB
Pin 19=1.0V
min
typ
0.077
fc
Overheat detection temperature
TSD
Design guarantee
Drain-to-Source leakage current
IDSS
VDS=100V,
Pins 2, 6, 9, and 18=GND
unit
8
0.093
0.109
A
1.16
1.7
V
0.61
0.80
V
2.5
0.25
V
10
μA
0.01
0.20
2.4
2.5
2.6
3.1
3.3
3.5
50
75
45
V
0.5
0.00
29
mA
V
0.8
Pins 10, 12, 13, 14, 15, 17=5V
PWM frequency
max
5
V
μA
10
μA
1
μA
61
kHz
°C
144
1
μA
* Maximum value of operating supply voltage 1 (VCC) can not supply to STK672-612B-E, depending on motor current
value. Refer to “8. Precautions, etc” of Usage Notes.
*Ioave values are for when the lead frame of the product is soldered to the mounting substrate.
Notes: A fixed-voltage power supply must be used.
No. A2114-2/26
STK672-612B-E
Package Dimensions
unit:mm (typ)
24.2
(18.4)
4.5
11.0
(11.0)
14.4
14.4
(R1.47)
19
(3.5)
1
1.0
0.4
0.5
2.0
18 1.0=18.0
4.0
4.45
Derating curve of motor current, IOH, vs. STK672-612B-E Operating substrate temperature, Tc
IOH - Tc
1.2
200Hz 2-phase excitation
Motor current, IOH - A
1.0
Hold mode
0.8
0.6
0.4
0.2
0
0
10
20
30
40
50
60
70
80
90
100
110
Operating Substrate Temperature, Tc - °C
Notes
• The current range given above represents conditions when output voltage is not in the avalanche state.
• If the output voltage is in the avalanche state, see the allowable avalanche energy for STK672-6** series hybrid ICs given
in a separate document.
• The operating substrate temperature, Tc, given above is measured while the motor is operating.
Because Tc varies depending on the ambient temperature, Ta, the value of IOH, and the continuous or intermittent
operation of IOH, always verify this value using an actual set.
• The Tc temperature should be checked in the center of the metal surface of the product package.
No. A2114-3/26
STK672-612B-E
Block Diagram
FAULT2
VrefOP
8
VDD=5V
9
7
A
AB
B
BB
4
5
3
1
VDD
F1
MODE1 10
N.C 11
MODE2 17
CLOCK 12
Excitation mode
selection
F2
F3
F4
FAO
Phase
excitation
signal
generator
Phase
advance
counter
FAB
FBO
FBB
CWB 13
RESETB 14
Power-on
reset
ENABLE 15
Latch
Circuit
Output
open
detection
Latch
Circuit
Overcurrent
detection
R1
R2
2
P.G2
6
P.G1
AI
FAULT1 16
Current control
chopper circuit
FAULT1
FAULT2
signal
Overheating
detection
BI
Vref/4.9
Latch
Circuit
Vref
Amplifier
VSS
VSS
N.C 18
Vref 19
Sample Application Circuit
STK672-612B-E
VDD(5V)
9
CLOCK
12
MODE1
10
MODE2
17
CWB
13
ENABLE
15
RESETB
R01
2 phase stepping motor driver
4
5
3
14
1
A
B
BB
+
R03
16
FAULT1
2
8
FAULT2
Vref
R02
0.1μF
C02
VCC
24V
AB
6
19
C01
at least 100μF
P.G2
P.G1
P.GND
18
N.C
No. A2114-4/26
STK672-612B-E
Precautions
[GND wiring]
• To reduce noise on the 5V system, be sure to place the GND of C01 in the circuit given above as close as possible to
Pin 2 and Pin 6 of the hybrid IC. Also, to achieve accurate current settings, be sure to connect Vref GND to the point
where P.G1 and P.G2 share a connection.
[Input pins]
• If VDD is being applied, use care that each input pin does not apply a negative voltage less than -0.3V to S.G, Pin 18,
and do not apply a voltage greater than or equal to VDD voltage.
• Do not wire by connecting the circuit pattern on the P.C.B side to N.C Pins. shown in the internal block diagram.
• Apply 2.5V high level input to pins 10, 12, 13, 14, 15, and 17.
• Since the input pins do not have built-in pull-up resistors, when the open-collector type pins 10, 12, 13, 14, 15, and 17
are used as inputs, a 1 to 20kΩ pull-up resistor (to VDD) must be used. At this time, use a device for the open
collector driver that has output current specifications that pull the voltage down to less than 0.8V at Low level (less
than 0.8V at Low level when IOL=5mA).
[Current setting Vref]
If the motor current is temporarily reduced, the circuit given below (STK672-612B-E : IOH>0.073A) is recommended.
5V
5V
R01
R01
Vref
Vref
R02
R3
R3
R02
• Motor current peak value IOH setting
IOH
0
IOH=(Vref÷4.9) ÷Rs
The value of 4.9 in Equation above represents the Vref voltage as divided by a circuit inside the control IC.
Vref=(R02÷ (R01+R02)) ×5V(or 3.3V)
Rs is an internal current detection resistor value of the hybrid IC.
Rs=0.39Ω when using the STK672-612B-E
No. A2114-5/26
STK672-612B-E
Input Pin Functions
Pin Name
Pin No.
Function
CLOCK
12
Reference clock for motor phase current switching
MODE1
10
Excitation mode selection
Input Conditions When Operating
Operates on the rising edge of the signal (MODE2=H)
Low: 2-phase excitation
High: 1-2 phase excitation
MODE2
17
High: Rising edge
CWB
13
Motor direction switching
RESETB
14
System reset
Low: Rising and falling edge
Low: CW (forward)
High: CCW (reverse)
A reset is applied by a low level
Initial state of A and BB phase excitation in the timing
charts is set by switching from low to high.
ENABLE
15
The A, AB, B, and BB outputs are turned off, and after
The A, AB, B, and BB outputs are turned off by a low-
operation is restored by returning the ENABLE pin to the
level input.
high level, operation continues with the same excitation
timing as before the low-level input.
Output Pin Functions
Pin Name
Pin No.
FAULT1
16
FAULT2
8
Function
Monitor pin used when opened motor pin, over-current
Input Conditions When Operating
Low level is output when detected.
detection, or overheat detection function is activated.
The result of activation of protection circuit detection is
3 levels output voltage
output.
VrefOP
7
Monitor pin of reference voltage used when opened motor
Normal DC voltage output (typ98mV)
pin detection.
Note: See the timing chart for the concrete details on circuit operation.
No. A2114-6/26
STK672-612B-E
Timing Charts
2-phase excitation
VDD
Power On Reset
(or RESETB)
MODE1
MODE2
CWB
CLOCK
ENABLE
FAO
FAB
FBO
FBB
1-2 phase excitation
VDD
Power On Reset
(or RESETB)
MODE1
MODE2
CWB
CLOCK
ENABLE
FAO
FAB
FBO
FBB
No. A2114-7/26
STK672-612B-E
1-2 phase excitation (CWB)
VDD
Power On Reset
(or RESETB)
MODE1
MODE2
CWB
CLOCK
ENABLE
FAO
FAB
FBO
FBB
2 phase excitation → Switch to 1-2 phase excitation
VDD
Power On Reset
(or RESETB)
MODE1
MODE2
CWB
CLOCK
ENABLE
FAO
FAB
FBO
FBB
No. A2114-8/26
STK672-612B-E
1-2 phase excitation (ENABLE)
VDD
Power On Reset
(or RESETB)
MODE1
MODE2
CWB
CLOCK
ENABLE
FAO
FAB
FBO
FBB
1-2 phase excitation (Hold operation results during fixed CLOCK)
VDD
Power On Reset
(or RESETB)
MODE1
MODE2
CWB
CLOCK
ENABLE
Hold operation
FAO
FAB
FBO
FBB
No. A2114-9/26
STK672-612B-E
2 phase excitation (MODE 2)
VDD
Power On Reset
(or RESETB)
MODE1
MODE2
CWB
CLOCK
ENABLE
FAO
FAB
FBO
FBB
1-2 phase excitation (MODE 2)
VDD
Power On Reset
(or RESETB)
MODE1
MODE2
CWB
CLOCK
ENABLE
FAO
FAB
FBO
FBB
No. A2114-10/26
STK672-612B-E
Usage Notes
1. STK672-612B-E input signal functions and timing
[ENABLE, CLOCK and power on reset, RESETB (Input signal timing when power is first applied)]
The control IC of the driver is equipped with a power on reset function capable of initializing internal IC operations
when power is supplied. A 4V typ setting is used for power on reset. Because the specification for the MOSFET gate
voltage is 5V±5%, conduction of current to output at the time of power on reset adds electromotive stress to the
MOSFET due to lack of gate voltage. To prevent electromotive stress, be sure to set ENABLE=Low while VDD, which
is outside the operating supply voltage, is less than 4.75V.
In addition, if the RESETB terminal is used to initialize output timing, be sure to allow at least 10μs until CLOCK
input.
3.8V typ
4V typ
Control IC power (VDD) rising edge
Control IC power on reset
RESETB signal input
No time specification
ENABLE signal input
CLOCK signal input
At least 10μs
At least 10μs
ENABLE, CLOCK, and RESETB Signals Input Timing
[CLOCK (Phase switching clock)]
• Input frequency: DC to 50kHz
• Minimum pulse width: 10μs
• MODE2=1(High) Signals are read on the rising edge.
• MODE2=0(Low) Signals are read on the rising and falling edges.
[CWB (Motor direction setting)]
The direction of rotation is switched by setting CWB to 1 (high) or 0 (low).
See the timing charts for details on the operation of the outputs.
Note: The state of the CWB input must not be changed during the 6.25μs period before and after the rising edge of the
CLOCK input.
[ENABLE (Forcible on/off control of the A, AB, B, and BB outputs, and hybrid IC internal operation)]
ENABLE=1: Normal operation
ENABLE=0: Outputs A, AB, B, and BB forced to the off state.
If, during the state where CLOCK signal input is provided, the ENABLE pin is set to 0 and then is later
restored to the 1 state, the IC will resume operation with the excitation timing continued from before the
point ENABLE was set to 0.
If sudden stop is applied to the CLOCK signal used for motor rotation, the motor axis may advance beyond the
theoretical position due to inertia. To stop at the theoretical position, the SLOW DOWN setting for gradually slowing
the CLOCK cycle is required.
No. A2114-11/26
STK672-612B-E
[MODE1 and MODE2 (Excitation mode selection)]
MODE1=0: 2-phase excitation
MODE2=1: Rising edge of CLOCK
MODE1=1: 1-2 phase excitation
MODE2=0: Rising and falling edges of CLOCK
See the timing charts for details on output operation in these modes.
Note: The state of the MODE input must not be changed during the 5μs period before and after the rising edge of the
CLOCK input.
The CLOCK input must not be changed during the period from when the signal changes from high to low or low
to high in MODE1 or MODE2, till when the signal changes from high to low or low to high in CWB.
[Configuration of Each Input Pin]
<Configuration of the MODE1, MODE2, CLOCK,
CWB, ENABLE, and RESETB input pins>
5V
<Configuration of the FAULT2 pin>
Output pin
Pin 8
10kΩ
Input pin
5V
50kΩ
50kΩ
50kΩ
100kΩ
VSS
Opened motor pin
Overcurrent
Thermal shutdown
(Configuration of the buffer is open drain.)
All input pins of this driver support schmitt input. Typ specifications at Tc = 25°C are given below. Hysteresis voltage
is 0.3V (VIHa-VILa).
When rising
When falling
1.8V typ
1.5V typ
Input voltage
VILa
VIHa
Input voltage specifications are as follows.
VIH=2.5V min
VIL=0.8V max
<Configuration of the Vref input pin>
<Configuration of the FAULT1 output pin>
5V
Output pin
Pin 16
Vref/4.9
−
Amplifier
VSS
Opened motor pin
Overcurrent
Thermal shutdown
+
Input pin
Pin 19
VSS
No. A2114-12/26
STK672-612B-E
<FAULT1, FAULT2 output>
FAULT1 Output
FAULT1 is an open drain output. Low is output if either overcurrent or overheating is detected.
FAULT2 output
Output is resistance divided (3 levels) and the type of abnormality detected is converted to the corresponding output
voltage.
• Opened motor pin: 10mV (typ)
• Overcurrent: 2.5V (typ)
• Overheat: 3.3V (typ)
Abnormality detection can be released by a RESETB operation or turning VDD voltage on/off.
<VrefOP output pin configuration>
5V
1.3V
180kΩ
Output pin
Pin 7
17kΩ
-
To opened motor pin
detection circuit
1kΩ
+
VSS
<VrefOP output>
To set the motor current detection circuit operates when pin is open, to monitor the reference voltage VrefOP
terminal. It is also possible to set any detectable current by connecting an external pull-up resistor to 5V supply.
<IOHd by setting pull-up resistor current sensing pin 7 open>
When 7 pins open, VrefOP (typ) is 98mV. In this case, detection current IOHd is expressed as follows.
VefOP = IOHd × Rs (Rs: Current detection resistor)
Detection current is 0.25A.
Now, detection current greater than 0.25A is IOHdX. Reference voltage VrefOPX is calculated as above.
Pull-up resistor Rdx by pin 7 is calculated as follows.
RdX = (180 × RTX) ÷ (180 - RTX)
RTX = (5.0V - VrefOPX) ÷ ((1.0588 × VrefOPX) - 0.0765) (RdX and RTX unit is kΩ)
*To disable pin open detection, please connect a 5V pull-up resistor of 10k to 15kΩ.
No. A2114-13/26
STK672-612B-E
2. STK672-612B-E overcurrent detection, overheat detection, and motor terminal open detection functions
Each detection function operates using a latch system and turns output off. Because a RESET signal is required to
restore output operations, once the power supply, VDD, is turned off, you must either again apply power on reset with
VDDON or apply a RESETB=High→Low→High signal.
[Motor terminal open detection]
This hybrid IC is equipped with a function for detecting open output terminals to prevent thermal destruction of the
MOSFET due to repeated avalanche operation that occurs when an output terminal connected to the motor is open.
The open condition is determined by checking the presence or absence of the flyback current that flows in the motor
inductance during the off period of the PWM cycle. Detection is performed by using the fact that the flyback current
does not flow when a motor terminal is open.
Terminal open
Used to see the motor current
Current detection
resistor voltage
0V (GND potential)
Used for open detection
(Negative current does not flow
when the terminal is open.)
MOSFET gate signal
PWM period
When the current level drops, the difference with the GND potential decreases, making detection difficult. The motor
current that can be detected by motor terminal open detection is 0.25A or more with the STK672-612B-E.
<Notes on the ENABLE high edge>
When ENABLE changes from low to high and the STK672-6XXB-E performs constant-current PWM operation that
flows a negative current during the 30μs period after the high edge, open detection may activate and stop the driver.
The motor current setting voltage Vref must be set so that PWM operation is not performed within a period of 30μs
after the high edge.If the motor current setup voltage is set for the rated motor current, PWM operation is not
performed during this 30μs period after the high edge, so this is not a problem.
In addition, there is no problem with operation that lowers the current setting Vref after the motor rated current is
reached as shown in the diagram on the following page. Whether constant-current PWM operation is performed
during the 30μs period after the high edge can be judged by substituting the motor L and R values into the formula
on the following page.
Vref= (R02 ÷ (R01+R02)) × 5V (or 3.3V)
IOH1= (Vref ÷ 4.9) ÷ Rs
IOH1: Motor current value to be set
IOH2= (VCC ÷ R) × (1-e-t(R/L))
IOH2: Current value 30μs after the ENABLE high edge
⇒ Judgment standard: IOH1>IOH2
R01, R02, 5V (or 3.3V): See the Sample Application Circuit documents.
Rs: Current detection resistance value (Ω)
VCC: Motor supply voltage (V)
R: Motor winding resistance (Ω)
L: Motor winding inductance (H)
⇒ There is no problem if the IOH2 obtained by substituting t = 30μs and the motor L and R values is smaller than
the current setting value IOH1.
No. A2114-14/26
STK672-612B-E
ENABLE
Vref
Output current
Constant-current PWM operation must not be performed for 30 µs or less.
<Connection of capacitors between output pins and GND prohibited>
Capacitors must not be connected between the phase A (pin 4), phase AB (pin 5), phase B (pin 3) and phase BB
(pin 1) outputs and GND. What happens if capacitors are connected is that open-circuit detection may be triggered
by the discharge current of the capacitors when the internal MOSFET is set ON. This current is not an inductance
current generated by the motor winding but a capacitor current so a negative current will not flow to the other phase
in each pair of phases, possibly causing the driver to shut down.
<Excessive external noise>
If, when the motor current rises prior to the PWM operation, a spike-shaped current exceeding the Vref-setting
current is generated by excessive external noise, for instance, before the current level (0.5A for the STK672-632B-E
and 630B-E, 0.8A for the STK672-642B-E and 640B-E motor drivers) at which motor pin open-circuiting can be
detected is reached, the internal MOSFET is set OFF. Since the MOSFET has been set OFF before the actual motor
current reaches 0.5A (or 0.8A), the level of the negative current subsequently flowing to the other phase in each pair
of phases is low, and it may be judged that no negative current is flowing, possibly causing open-circuit detection to
be triggered.
During normal constant-current PWM operation, the duration of 5.5μs, which is equivalent to 25% of the initial
operation in the PWM period, corresponds to the section where the current is not detected, and this ensures that no
current is detected for the linking part of the current that is generated in this section. The no-current detection
section is not synchronized at the current rise prior to the PWM operation so when a spike-shaped current exceeding
the Vref-setting current is generated, the MOSFET is set OFF at the stage where the level of the actual motor
current is low. As a result, the level of the negative current subsequently flowing to the other phase in each pair of
phases is low, and it may be judged that no negative current is flowing, possibly causing open-circuit detection to be
triggered.
Spike-shaped current
Vref setting
current (IOH)
Motor
current
Current level at
which opencircuiting is
detected
No-current detection time (5.5μs typ)
PWM period
No. A2114-15/26
STK672-612B-E
[Overcurrent detection]
This hybrid IC is equipped with a function for detecting overcurrent that arises when the motor burns out or when there
is a short between the motor terminals.
Over current detection occurs at 1.2A typ with the STK672-612B-E.
Current when motor terminals are shorted
PWM period
Set motor
current,
IOH
Over current detection
IOH max
MOSFET all OFF
No detection interval
(5.5μs typ)
Normal operation
5.5μs typ
Operation when motor pins are shorted
Over current detection begins after an interval of no detection (a dead time of 5.5μs typ) during the initial ringing part
during PWM operations. The no detection interval is a period of time where over current is not detected even if the
current exceeds IOH.
[Overheat detection]
Rather than directly detecting the temperature of the semiconductor device, overheat detection detects the temperature
of the aluminum substrate (144°C typ).
Within the allowed operating range recommended in the specification manual, if a heat sink attached for the purpose of
reducing the operating substrate temperature, Tc, comes loose, the semiconductor can operate without breaking
However, we cannot guarantee operations without breaking in the case of operations other than those recommended,
such as operations at a current exceeding IOH max that occurs before overcurrent detection is activated.
No. A2114-16/26
STK672-612B-E
3. Calculating STK672-612B-E HIC Internal Power Loss
The average internal power loss in each excitation mode of the STK672-612B-E can be calculated from the following
formulas.
Each excitation mode
2-phase excitation mode
2PdAVex=2×Vsat×0.5×CLOCK×IOH×t2+0.5×CLOCK×IOH× (Vsat×t1+Vdf×t3)
1-2 Phase excitation mode
1-2PdAVex=2×Vsat×0.25×CLOCK×IOH×t2+0.25×CLOCK×IOH× (Vsat×t1+Vdf×t3)
Motor hold mode
HoldPdAVex= (Vsat+Vdf)×IOH
Vsat: Combined voltage of Ron voltage drop + current detection resistance
Vdf: Combined voltage of the FET body diode + current detection resistance
CLOCK: Input CLOCK (CLOCK pin signal frequency)
t1, t2, and t3 represent the waveforms shown in the figure below.
t1: Time required for the winding current to reach the set current (IOH)
t2: Time in the constant current control (PWM) region
t3: Time from end of phase input signal until inverse current regeneration is complete
IOH
0A
t1
t2
t3
Motor COM Current Waveform Model
t1= (-L/(R+0.61)) ln (1-((R+0.61)/VCC) ×IOH)
t3= (-L/R) ln ((VCC+0.61)/(IOH×R+VCC+0.61))
VCC: Motor supply voltage (V)
L: Motor inductance (H)
R: Motor winding resistance (Ω)
IOH: Motor set output current crest value (A)
Relationship of CLOCK, t1, t2, and t3 in each excitation mode
2-phase excitation mode: t2= (2/CLOCK) - (t1+t3)
1-2 phase excitation mode: t2= (3/CLOCK) -t1
For Vsat and Vdf, be sure to substitute values from the graphs of Vsat vs. IOH and Vdf vs. IOH while the set current
value is IOH.
Then, determine whether a heat sink is required by comparing with the graph of ΔTc vs. Pd based on the average HIC
power loss calculated.
When designing a heat sink, refer to the section “Thermal design” found on the next page. The average HIC power
loss, PdAV, described above does not have the avalanche’s loss. To include the avalanche’s loss, be sure to add
Equation (2), “STK672-6** Allowable Avalanche Energy Value” to PdAV above. When using this IC without a fin
always check for temperature increases in the set, because the HIC substrate temperature, Tc, varies due to effects of
convection around the HIC.
No. A2114-17/26
STK672-612B-E
STK672-612B-E Output saturation voltage, Vsat - Output current, IOH
Vsat - IOH
0.6
°C
°C
25
Tc
=1
05
Output saturation voltage, Vsat - V
0.7
0.5
0.4
0.3
0.2
0.1
0
0
0.2
0.4
0.6
0.8
1.0
1.2
Output current, IOH - A
STK672-612B-E Forward voltage, Vdf -Output current, IOH
Vdf- IOH
1.4
Forward voltage, Vdf - V
1.2
25°C
Tc=
°C
105
1.0
0.8
0.6
0.4
0.2
0
0
0.2
0.4
0.6
0.8
1.0
1.2
Output current, IOH - A
Substrate temperature rise, ΔTc (no heat sink) - Internal average power dissipation, PdAV
ΔTc - PdAV
Substrate temperature rise, ΔTc - °C
80
70
60
50
40
30
20
10
0
0
0.5
1.0
1.5
2.0
2.5
Hybrid IC internal average power dissipation, PdAV - W
3.0
ITF02717
No. A2114-18/26
STK672-612B-E
4. STK672-612B-E Allowable Avalanche Energy Value
(1) Allowable Range in Avalanche Mode
When driving a 2-phase stepping motor with constant current chopping using an STK672-6** Series hybrid IC,
the waveforms shown in Figure 1 below result for the output current, ID, and voltage, VDS.
VDSS: Voltage during avalanche operations
VDS
IOH: Motor current peak value
IAVL: Current during avalanche operations
ID
tAVL: Time of avalanche operations
ITF02557
Figure 1 Output Current, ID, and Voltage, VDS, Waveforms 1 of the STK672-6** Series when
Driving a 2-Phase Stepping Motor with Constant Current Chopping
When operations of the MOSFET built into STK672-6** Series ICs is turned off for constant current chopping,
the ID signal falls like the waveform shown in the figure above. At this time, the output voltage, VDS, suddenly
rises due to electromagnetic induction generated by the motor coil.
In the case of voltage that rises suddenly, voltage is restricted by the MOSFET VDSS. Voltage restriction by
VDSS results in a MOSFET avalanche. During avalanche operations, ID flows and the instantaneous energy at
this time, EAVL1, is represented by Equation (1).
EAVL1=VDSS×IAVL×0.5×tAVL ------------------------------------------- (1)
VDSS: V units, IAVL: A units, tAVL: sec units
The coefficient 0.5 in Equation (1) is a constant required to convert the IAVL triangle wave to a
square wave.
During STK672-6** Series operations, the waveforms in the figure above repeat due to the constant current
chopping operation. The allowable avalanche energy, EAVL, is therefore represented by Equation (2) used to find
the average power loss, PAVL, during avalanche mode multiplied by the chopping frequency in Equation (1).
PAVL=VDSS×IAVL×0.5×tAVL×fc ------------------------------------------- (2)
fc: Hz units (fc is set to the PWM frequency of 50kHz.)
For VDSS, IAVL, and tAVL, be sure to actually operate the STK672-6** Series and substitute values when
operations are observed using an oscilloscope.
Ex. If VDSS=110V, IAVL=1A, tAVL=0.2μs when using a STK672-612B-E driver, the result is:
PAVL=110×0.5×0.5×0.2×10-6×50×103=0.28W
VDSS=110V is a value actually measured using an oscilloscope.
The allowable loss range for the allowable avalanche energy value, PAVL, is shown in the graph in Figure 3.
When examining the avalanche energy, be sure to actually drive a motor and observe the ID, VDSS, and tAVL
waveforms during operation, and then check that the result of calculating Equation (2) falls within the allowable
range for avalanche operations.
No. A2114-19/26
STK672-612B-E
(2) ID and VDSS Operating Waveforms in Non-avalanche Mode
Although the waveforms during avalanche mode are given in Figure 1, sometimes an avalanche does not result during
actual operations.
Factors causing avalanche are listed below.
• Poor coupling of the motor’s phase coils (electromagnetic coupling of A phase and AB phase, B phase and
BB phase).
• Increase in the lead inductance of the harness caused by the circuit pattern of the P.C. board and motor.
• Increases in VDSS, tAVL, and IAVL in Figure 1 due to an increase in the supply voltage from 24V to 36V.
If the factors above are negligible, the waveforms shown in Figure 1 become waveforms without avalanche as
shown in Figure 2.
Under operations shown in Figure 2, avalanche does not occur and there is no need to consider the allowable loss
range of PAVL shown in Figure 3.
VDS
IOH: Motor current peak value
ID
ITF02558
Figure 2 Output Current, ID, and Voltage, VDS, Waveforms 2 of the STK672-6** Series when Driving a
2-Phase Stepping Motor with Constant Current Chopping
Average power loss in the avalanche state, PAVL - W
Figure 3 Allowable Loss Range, PAVL-IOH During STK672-612B-E Avalanche Operations
PAVL - IOH
4.0
Tc=80°C
3.5
3.0
105°C
2.5
2.0
1.5
1.0
0.5
0
0
0.2
0.4
0.6
0.8
1.0
Motor phase current, IOH - A
Note:
The operating conditions given above represent a loss when driving a 2-phase stepping motor with constant current
chopping.
Because it is possible to apply 2.6W or more at IOH=0A, be sure to avoid using the MOSFET body diode that is used
to drive the motor as a zener diode.
No. A2114-20/26
STK672-612B-E
5. Thermal design
[Operating range in which a heat sink is not used]
Use of a heat sink to lower the operating substrate temperature of the HIC (Hybrid IC) is effective in increasing the
quality of the HIC.
The size of heat sink for the HIC varies depending on the magnitude of the average power loss, PdAV, within the HIC.
The value of PdAV increases as the output current increases. To calculate PdAV, refer to “Calculating Internal HIC
Loss for the STK672-612B-E” in the specification document.
Calculate the internal HIC loss, PdAV, assuming repeat operation such as shown in Figure 1 below, since conduction
during motor rotation and off time both exist during actual motor operations,
IO1
Motor phase current
(sink side)
IO2
0A
-IO1
T1
T2
T3
T0
Figure 1 Motor Current Timing
T1: Motor rotation operation time
T2: Motor hold operation time
T3: Motor current off time
T2 may be reduced, depending on the application.
T0: Single repeated motor operating cycle
IO1 and IO2: Motor current peak values
Due to the structure of motor windings, the phase current is a positive and negative current with a pulse form.
Note that figure 1 presents the concepts here, and that the on/off duty of the actual signals will differ.
The hybrid IC internal average power dissipation PdAV can be calculated from the following formula.
PdAV= (T1×P1+T2×P2+T3×0) ÷TO ---------------------------- (I)
(Here, P1 is the PdAV for IO1 and P2 is the PdAV for IO2)
If the value calculated using Equation (I) is 1.5W or less, and the ambient temperature, Ta, is 60°C or less, there is no
need to attach a heat sink. Refer to Figure 2 for operating substrate temperature data when no heat sink is used.
[Operating range in which a heat sink is used]
Although a heat sink is attached to lower Tc if PdAV increases, the resulting size can be found using the value of
θc-a in Equation (II) below and the graph depicted in Figure 3.
θc-a= (Tc max-Ta) ÷PdAV ---------------------------- (II)
Tc max: Maximum operating substrate temperature =105°C
Ta: HIC ambient temperature
Although a heat sink can be designed based on equations (I) and (II) above, be sure to mount the HIC in a set and
confirm that the substrate temperature, Tc, is 105°C or less.
The average HIC power loss, PdAV, described above represents the power loss when there is no avalanche operation.
To add the loss during avalanche operations, be sure to add Equation (2), “Allowable STK672-6** Avalanche Energy
Value”, to PdAV.
No. A2114-21/26
STK672-612B-E
Figure 2 Substrate temperature rise, ΔTc (no heat sink) - Internal average power dissipation, PdAV
ΔTc - PdAV
Substrate temperature rise, ΔTc - °C
80
70
60
50
40
30
20
10
0
0
0.5
1.0
1.5
2.0
2.5
3.0
Hybrid IC internal average power dissipation, PdAV - W
ITF02717
Figure 3 Heat sink area (Board thickness: 2mm) - θc-a
θc-a - S
Heat sink thermal resistance, θc-a - °C/W
100
7
5
3
2
Wit
10
Wi t
7
5
ha
3
2
1.0
10
2
3
5
hn
o su
rfac
e fi
nish
flat
blac
k su
rfac
e fi
nish
7
100
2
3
5
Heat sink area, S - cm2
7 1000
ITF02554
6. Mitigated Curve of Package Power Loss, PdPK, vs. Ambient Temperature, Ta
Package power loss, PdPK, refers to the average internal power loss, PdAV, allowable without a heat sink.
The figure below represents the allowable power loss, PdPK, vs. fluctuations in the ambient temperature, Ta.
Power loss of up to 3.1W is allowable at Ta=25°C, and of up to 1.75W at Ta=60°C.
Allowable power dissipation, PdPK(no heat sink) - Ambient temperature, Ta
PdPK - Ta
Allowable power dissipation, PdPK - W
3.0
2.5
2.0
1.0
1.5
0.5
0
0
20
40
60
80
Ambient Temperature, Ta - °C
100
120
ITF02718
No. A2114-22/26
STK672-612B-E
7. Example of Stepping Motor Driver Output Current Path (1-2 phase excitation)
2-phase stepping motor
IOAB
IOA
FAULT2 VrefOP
8
VDD=5V 9
MODE1 10
N.C 11
VDD
Excitatin
mode setting
MODE2 17
RESETB 14
5
F1
Phase
excitation
signal
generation
Power
on
reset
ENABLE 15
Over heat
detection
N.C 18
BB
1
F2
F3
F4
Latch
Opened
motor pin
detection
Latch
Over
current
detection
FAB
FBO
VCC
24V
FBB
R1
AI
FAULT1,
FAULT2
signal
FAULT1 16
B
3
FAO
Phase
advnce
counter
CLOCK 12
CWB 13
AB
A
4
7
Latch
Chopper
circuit
BI
Vref/4.9
R2
P.G2
2
P.G1
6
C02
at least 100μF
P.GND
Vref
Amp
VSS
VSS
Vref 19
CLOCK
Phase A output
current
IOA
PWM operations
Phase AB output
current
When PWM operations of IOA
are OFF, for IOAB, negative
current flows through the
parasitic diode, F2.
IOAB
When PWM operations of IOAB
are OFF, for IOA, negative
current flows through the
parasitic diode, F1.
No. A2114-23/26
STK672-612B-E
8. Other Notes on Use
In addition to the “Notes” indicated in the Sample Application Circuit, care should also be given to the following
contents during use.
(1) Allowable operating range
Operation of this product assumes use within the allowable operating range. If a supply voltage or an input
voltage outside the allowable operating range is applied, an overvoltage may damage the internal control IC or
the MOSFET.
If a voltage application mode that exceeds the allowable operating range is anticipated, connect a fuse or take
other measures to cut off power supply to the product.
(2) Input pins
If the input pins are connected directly to the PC board connectors, electrostatic discharge or other overvoltage
outside the specified range may be applied from the connectors and may damage the product. Current generated
by this overvoltage can be suppressed to effectively prevent damage by inserting 100Ω to 1kΩ resistors in lines
connected to the input pins.
Take measures such as inserting resistors in lines connected to the input pins.
(3) Power connectors
If the motor power supply VCC is applied by mistake without connecting the GND part of the power connector
when the product is operated, such as for test purposes, an overcurrent flows through the VCC decoupling
capacitor, C1, to the parasitic diode between the VDD of the internal control IC and GND, and may damage the
power supply pin block of the internal control IC.
To prevent destruction in this case, connect a 10Ω resistor to the VDD pin, or insert a diode between the VCC
decoupling capacitor C1 GND and the VDD pin.
Overcurrent protection measure: Insert a resistor.
VDD=5V
5V
Reg.
9
A
4
VDD
AB
5
F1
F2
B
3
BB
1
F3
F4
FAO
MODE1
FABO
FBO
CLOCK
FBBO
VCC
CWB
RESETB
R1
ENABLE
AI
MODE2
BI
R2
GND
2
C1
24V
Reg.
6
Vref
FAULT1
Vref
18
VSS
N.C
open
Overcurrent protection measure: Insert a diode.
Over-current path
(4) Input Signal Lines
1) Do not use an IC socket to mount the driver, and instead solder the driver directly to the PC board to minimize
fluctuations in the GND potential due to the influence of the resistance component and inductance component
of the GND pattern wiring.
2) To reduce noise caused by electromagnetic induction to small signal lines, do not design small signal lines
(sensor signal lines, and 5V or 3.3V power supply signal lines) that run parallel in close proximity to the motor
output line A (Pin 4), AB (Pin 5), B (Pin 3), or BB (Pin 1) phases.
3) Pin 11 of this product are N.C pins. Do not connect any wiring to these pins.
No. A2114-24/26
STK672-612B-E
(5) When mounting multiple drivers on a single PC board
When mounting multiple drivers on a single PC board, the GND design should mount a VCC decoupling
capacitor, C1, for each driver to stabilize the GND potential of the other drivers. The key wiring points are as
follows.
24V
5V
9
9
Input
Signals
Motor
1
IC1
9
Motor
2
Input
Signals
IC2
2
2
6
6
Motor
3
Input
Signals
IC3
2
6
19 18
19 18
19 18
GND
GND
Short
Thick
Thick and short
(6) VCC operating limit
When the output (for example F1) of a 2-phase stepping motor driver is turned OFF, the AB phase back
electromotive force eab produced by current flowing to the paired F2 parasitic diode is induced in the F1 side,
causing the output voltage VFB to become twice or more the VCC voltage. This is expressed by the following
formula.
VFB = VCC + eab
= VCC + VCC + IOH × RM + Vdf (1.5 V)
VCC: Motor supply voltage, IOH: Motor current set by Vref
Vdf: Voltage drop due to F2 parasitic diode and current detection resistor R1, RM: Motor winding resistance
value
Using the above formula, make sure that VFB is always less than the MOSFET withstand voltage of 100V. This
is because there is a possibility that operating limit of VCC falls below the allowable operating range of 46V, due
to the RM and IOH specifications.
VCC
VCC
AB phase
A phase
AB phase
A phase
eab
Eab is induced by
inducing M.
The pass of
drain current
VFB
M
eab
F2
OFF
F1
ON
R1
GND
The pass of
negative current
M
VCC
F2
OFF
F1
OFF
R1
GND
The oscillating voltage in excess of VFB is caused by LCRM (inductance, capacitor, resistor, mutual inductance)
oscillation that includes micro capacitors C, not present in the circuit. Since M is affected by the motor
characteristics, there is some difference in oscillating voltage according to the motor specifications. In addition,
constant voltage drive without constant current drive enables motor rotation at VCC ≥ 0V.
No. A2114-25/26
STK672-612B-E
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products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition
ranges, or other parameters) listed in products specifications of any and all SANYO Semiconductor Co.,Ltd.
products described or contained herein.
Regarding monolithic semiconductors, if you should intend to use this IC continuously under high temperature,
high current, high voltage, or drastic temperature change, even if it is used within the range of absolute
maximum ratings or operating conditions, there is a possibility of decrease reliability. Please contact us for a
confirmation.
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semiconductor products fail or malfunction with some probability. It is possible that these probabilistic failures or
malfunction could give rise to accidents or events that could endanger human lives, trouble that could give rise
to smoke or fire, or accidents that could cause damage to other property. When designing equipment, adopt
safety measures so that these kinds of accidents or events cannot occur. Such measures include but are not
limited to protective circuits and error prevention circuits for safe design, redundant design, and structural
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Any and all information described or contained herein are subject to change without notice due to
product/technology improvement, etc. When designing equipment, refer to the "Delivery Specification" for the
SANYO Semiconductor Co.,Ltd. product that you intend to use.
Upon using the technical information or products described herein, neither warranty nor license shall be granted
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This catalog provides information as of August, 2012. Specifications and information herein are subject
to change without notice.
PS No. A2114-26/26