MITSUBISHI M54646AP

MITSUBISHI <CONTROL / DRIVER IC>
M54646AP
2-PHASE STEPPER MOTOR DRIVER
DESCRIPTION
The M54646AP is a semiconductor IC to drive bipolar stepper
motors by controlling winding current with reference to a
designated current level.
PIN CONFIGURATION (TOP VIEW)
Comparator input (1)
C1 →
Comparator reference
VR1 →
voltage input (1)
Output stage
VMM1
supply voltage (1)
Output terminal (1) MA1 ←
FEATURES
● Wide driver voltage range (10 – 40V)
● Wide output current control range (20 – 800mA)
● Bipolar and constant current control
● Built-in flywheel diode
● Built-in thermal protection circuit
1
28 ← C2
2
27 ← VR2
Comparator reference
voltage input (2)
26
VMM2 Output stage
supply voltage (2)
25 → MA2 Output terminal (2)
3
4
24 → E2
E1 ← 5
Current sensor (1)
7
Office automation equipment such as printers, FDDs, HDDs and
facsimiles
GND
8
9
FUNCTION
22
GND
21
20
Output terminal (1) MB1 ← 10
M54646AP Integrated Circuit drives two-phase bipolar stepper
motors while controlling winding current: It controls winding current
direction by inputting phases (pins 14 and 15) and, at the same
time, controls winding current amperage with terminals VR (pins
2 and 27 ).
Provided with control circuits that output two phases, this IC is
sufficient to drive a two-phase bipolar stepper motor.
Output stage VMM1
supply voltage ((1)
Power supply (1) VCC1
One-shot multi
←
T1 →
time constant
Output current
Ph1 →
direction switch
Current sensor (2)
23
M54646AP
6
APPLICATION
Comparator input (2)
19 → MB2 Output terminal (2)
VMM2 Output stage
supply voltage (2)
17
VCC2 Power supply (2)
16 →
← T2 One-shot multi
time constant
15 ← Ph2 Output current
direction switch
11
18
12
13
14
Outline 28P4B
Direction switch
output current
Output stage
supply voltage (1)
MA2
MB2
VMM2
VR1
Ph1
VMM1
MA1
MB1
15
25
19
18
2
14
3
4
10
Output
terminal (2)
1
1
1
1
Output
terminal (1)
Comparator
reference
voltage input (1)
Ph2
27
Output current
direction switch
VR2
Comparator
reference
voltage input (2)
Output stage
supply voltage (2)
BLOCK DIAGRAM
1
1
Power
supply (1)
VCC1 12
Power
supply (2)
17 VCC2
1
1
1
1
TSD
Monostable
Monostable
tOFF = 0.69 • RT • CT
Current sensor
20 21 22 23 28
GND
C2
Comparator
input (2)
tOFF = 0.69 • RT • CT
Current sensor
16
T2
One-shot multi
time constant
24
6 7 8 9
E2
Current GND
sensor
1
C1
Comparator
input (1)
13
T1
One-shot multi
time constant (1)
5
E1
Current
sensor (1)
MITSUBISHI <CONTROL / DRIVER IC>
M54646AP
2-PHASE STEPPER MOTOR DRIVER
ABSOLUTE MAXIMUM RATINGS (Ta = 25°C unless otherwise noted)
Symbol
VCC
VMM
VL
VC
VR
IL
IC
IO
Pd
Topr
Tstg
Parameter
Conditions
Supply voltage
Output stage supply voltage
Logic input voltage
Analog input voltage
Reference input voltage
Logic input current
Analog input current
Output current
Power dissipation
Operating temperature
Storage temperature
Ratings
Unit
-0.3 – 7
-0.3 – 45
-0.3 – 6
V
V
V
V
V
mA
mA
mA
W
°C
°C
-0.3 – VCC
-0.3 – 15
-10
-10
±1000
1.92
-20 – 85
-55 – 125
Measured with IC mounted on board
RECOMMENDED OPERATIONAL CONDITIONS (Ta = 25°C unless otherwise noted)
Symbol
VCC
VMM
IO
tPLH
tPHL
TON
Parameter
Min.
4.5
10
20
Supply voltage
Output stage supply voltage
Output current
Logic input rise time
Logic input fall time
Thermal shutdown temperature
Limits
Typ.
5
165
Max.
5.5
40
800
2
2
Unit
V
V
mA
µs
µs
°C
ELECTRICAL CHARACTERISTICS (VCC = 5V, Ta = 25°C unless otherwise noted)
Symbol
VIH
VIL
ICH
ICO
IOFF
Parameter
Test Conditions
“H”
“L”
Comparator threshold voltage
Comparator input current
Output cutoff current
Logic input voltage
Vsat
Total saturation voltage
tOFF
td
ICC
IIH
IIL
Cutoff time
Turn-off delay
Power current
Logic input current
“H”
“L”
VCC = 5V
VR = 5V
Sensing resistance is not included.
(IO = 500mA)
VMM = 10V, tON ≥ 5µs
dVK/dt ≥ 50mV/µs
VCC = 5V, 1 phase
VI = 2.4V
VI = 0.4V
Min.
2.0
0
400
-20
25
-0.4
Limits
Typ.
430
30
1.6
Max.
VCC
0.8
450
20
100
Unit
V
V
mA
µA
µA
3.5
V
35
2.0
25
20
µs
µs
mA
µA
mA
MITSUBISHI <CONTROL / DRIVER IC>
M54646AP
2-PHASE STEPPER MOTOR DRIVER
SWITCHING CHARACTERISTICS
APPLICATION DIRECTIONS
(1) Phase input
Phase input determines output mode:
SWITCHING WAVEFORM
PHASE
H
L
VMA – VMB or VMB – VMA
MA
H
L
MB
L
H
tOFF=0.69 • RT • CT
1
1/2
tOFF
tON
td
VE
VCH
(2) VR (reference voltage)
Stepless current level variation is available by continuously
changing VR.
(3) Current sensor
Compares voltage converted from amperage by current
sensing resistor to designated reference voltage level. When
they are the same, comparator triggers Mono-stable, and shuts
off output transistor during time frame tOFF. During this period,
current level decreases to slightly below reference level. When
period has passed, output transistor is reactivated. This series
of operations is repeated.
(4) Single-pulse generator
Mono-stable is triggered at comparator output phase rise edge.
Mono-stable output pulse width is determined by input to timing
terminals RT and CT, as follows:
tOFF = 0.69 × RT × CT
If new trigger occurs during tOFF, it is ignored.
(5) Analog control
Stepless output current level variation is available by
continuously changing voltage VR or feedback voltage to
comparator.
TIMING CHART
Two-phase
excitation
Phase 1
Phase 2
MITSUBISHI <CONTROL / DRIVER IC>
M54646AP
2-PHASE STEPPER MOTOR DRIVER
AREA OF SAFE OPERATION
OUTPUT CURRENT Io (A)
1.0
A: Recommended operational range
B: External Schottky diode to be connected between output
terminal and power terminal as well as between output terminal
and GND.
0.8
B
0.6
✽
0.4
This regulation is for temporary electric power use. For
continuous use, be sure power dissipation does not go beyond
package’s operational range.
B
A
0.2
0
0
10
20
30
40 45 50
DRIVER VOLTAGE VMM (V)
THERMAL DERATING
POWER DISSIPATION (W)
10.0
θj-c = 8°C/W
A: Mounted on 25cm2 glassfiber epoxy resin circuit board with one
side copper-foiled
θc-a = 42°C/W
B: With aluminum heat sink (1t) 10cm2
θc-a = 25°C/W
C: With aluminum heat sink (1t) 100cm2
θc-a = 10°C/W
Tj(max) = 150°C
8.0
6.0
C
4.0
B
A
2.0
0
0
25
50
75
AMBIENT TEMPERATURE (°C)
100
MITSUBISHI <CONTROL / DRIVER IC>
M54646AP
2-PHASE STEPPER MOTOR DRIVER
APPLICATION EXAMPLE
CC1
CC2
1
C1
C2
28
2
VR1
VR2
27
3
VMM1
VMM2
26
4
MA1
MA2
25
5
E1
E2
24
24V
RC1
RC2
47µF
6
23
GND
8
M54646AP
7
RS1
22
RS2
GND
21
9
20
10
MB1
11
MB2
19
VMM1
VMM2
18
12
VCC1
VCC2
17
13
T1
T2
16
14
Ph1
Ph2
15
5V
CT1
CT2
RT1
Phase1
RT2
Phase2
Stepper motor
RS1, RS2 = 1Ω
RC1, RC2 = 1kΩ
CC1, CC2 = 820ρF
RT1, RT2 = 56kΩ
CT1, CT2 = 820ρF
MITSUBISHI <CONTROL / DRIVER IC>
M54646AP
2-PHASE STEPPER MOTOR DRIVER
CAUTION
(1) Be sure to short-circuit VCC1 and VCC2 before use.
(2) When IC total output current changes greatly, e.g. when output
current flows intermittently due to thermal protection operation,
supply voltage may fluctuate. Provide power supply and wiring
such that even in such a case amperage will not exceed
absolute maximum rating.
(3) Excessive power voltage fluctuations may cause unstable IC
operation. To regulate such fluctuations, connect capacitor
between terminals VCC and GND as close to IC terminal as
possible. (Refer to application example.)
(4) Thermal protection function
• Thermal protection characteristics may differ depending on
wiring layout. Be sure to test IC on circuit board before use.
After circuit board is replaced, test IC again.
• Circuit boards on which this IC mounted are designed such
that impedance between power supply and output terminal will
be kept low; therefore, IC output terminal may be shortcircuited internally if excessive surge voltage is applied
accidentally from outside. To prevent circuit board from
burning in such a case, take safety measures such as
installation of a fuse.
(5) Flywheel diode
This IC has built in flywheel diode to provide a return current
route to motor. To prevent overheating and malfunction in
operational areas where great current and voltage are applied,
install a Schottky diode externally. For details, refer to “Area of
Safe Operation” and “Application Example.”
.