ETC UC3770AQ

UC3770A
UC3770B
High Performance Stepper Motor Drive Circuit
FEATURES
DESCRIPTION
•
Full-Step, Half-Step and Micro-Step
Capability.
•
Bipolar Output Current up to 2A.
•
Wide Range of Motor Supply Voltage:
10–50V
•
Low Saturation Voltage
The UC3770A and UC3770B are high-performance full bridge drivers that offer higher current and lower saturation voltage than the
UC3717 and the UC3770. Included in these devices are LS-TTL
compatible logic inputs, current sense, monostable, thermal shutdown, and a power H-bridge output stage. Two UC3770As or
UC3770Bs and a few external components form a complete microprocessor-controllable stepper motor power system.
•
Wide Range of Current Control: 5mA–2A.
•
Current Levels Selected in Steps or Varied
Continuously.
•
Thermal Protection and Soft Intervention.
Unlike the UC3717, the UC3770A and the UC3770B require external high-side clamp diodes. The UC3770A and UC3770B are
identical in all regards except for the current sense thresholds.
Thresholds for the UC3770A are identical to those of the older
UC3717 permitting drop-in replacement in applications where
high-side diodes are not required. Thresholds for the UC3770B are
tailored for half stepping applications where 50%, 71%, and 100%
current levels are desirable.
The UC3770A and UC3770B are specified for operation from 0°C
to 70°C ambient.
BLOCK DIAGRAM
UDG-92039-1
SLUS403A - FEBRUARY 2000
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UC3770A
UC3770B
ABSOLUTE MAXIMUM RATINGS
Logic Supply Voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7V
Output Supply Voltage, VMM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50V
Logic Input Voltage (Pins 7, 8, 9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6V
Analog Input Voltage (Pin 10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VCC
Reference Input Voltage (Pin 11) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15V
Logic Input Current (Pins 7, 8, 9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –10mA
Analog Input Current (Pins 10, 11) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –10mA
Output Current (Pins 1, 15) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 2A
Junction Temperature, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +150°C
Note 1: All voltages are with respect to Gnd (DIL Pins 4, 5, 12, 13); all currents
are positive into, negative out of the specified terminal.
Note 2: Consult Unitrode Integrated Circuits databook for thermal limitations and
considerations of packages.
CONNECTION DIAGRAMS
DIL-16 (Top View)
J Or N Package
PACKAGE PIN FUNCTION
PLCC-28 (Top View)
Q Package
FUNCTION
PIN
Gnd
VM
N/C
AOUT
N/C
Emitters
Gnd
BOUT
Timing
VM
Gnd
VCC
I1
Phase
I0
N/C
Current
VR
N/C
Gnd
1-3
4
5
6
7
8
9
10
11
12
13-17
18
19
20
21
22
23
24
25-27
28
ELECTRICAL CHARACTERISTICS: (All tests apply with VM = 36V, VCC = 5V, VR = 5V, No Load, and 0°C<TA<70°C, unless
otherwise stated, TA = TJ.)
UC3770A
PARAMETER
TEST CONDITIONS
Supply Voltage VM (Pins 3, 14)
TYP
10
Logic Supply Voltage VCC (Pin 6)
Logic Supply Current ICC (Pin 6)
MIN
4.75
UC3770B
MAX
MIN
45
10
4.75
TYP
MAX UNITS
45
V
5
5.3
5
5.3
V
IO = I1 = H, IM = 0
15
25
15
25
mA
IO = I1 = L, IM = 0
18
28
18
28
mA
IO = I1 = H, IM = 1.3A
33
40
33
40
mA
Thermal Shutdown Temperature
+170
Logic Threshold (Pins 7, 8, 9)
0.8
°C
+170
2.0
0.8
2.0
V
Input Current Low (Pin 8)
VI = 0.4V
-100
-100
µA
Input Current Low (Pins 7, 9)
VI = 0.4V
-400
-400
µA
Input Current High (Pins 7, 8, 9)
VI = 2.4V
10
µA
Comparator Threshold (Pin 10)
VR = 5V, I0 = L, I1 = L
400
415
430
400
415
430
mV
VR = 5V, I0 = H, I1 = L
240
255
265
290
300
315
mV
VR = 5V, I0 = L, I1 = H
70
80
90
195
210
225
mV
±20
µA
35
ms
10
±20
Comparator Input Current (Pin 10)
Off Time
RT = 56k, CT = 820pF
25
2
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30
35
25
30
UC3770A
UC3770B
ELECTRICAL CHARACTERISTICS (cont.): (All tests apply with VM = 36V, VCC = 5V, VR = 5V, No Load, and 0°C<TA<70°C,
unless otherwise stated, TA = TJ.)
UC3770A
PARAMETER
TEST CONDITIONS
MIN
TYP
UC3770B
MAX
Turn Off Delay
Sink Driver Saturation Voltage
Source Driver Saturation Voltage
Output Leakage Current
MIN
2
2
ms
0.8
0.8
V
IM = 1.3A
1.3
1.3
V
IM = 1.0A
1.3
1.3
V
IM = 1.3A
1.6
1.6
V
VM = 45V
100
100
µA
TA = +25°C
1.8
5.0
1.6
4.5
ICC – mA
VCE SAT HIGH – V
MAX UNITS
IM = 1.0A
TA = +25°C
1.4
1.2
4.0
3.5
1.0
3.0
0.8
2.5
0.6
0.2
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
OUTPUT CURRENT – A
OUTPUT CURRENT – A
Figure 1. Typical source saturation voltages vs. load
current
Figure 3. Typical supply current vs. load current.
POWER DISSIPATION (W)
TA = +25°C
VCE SAT LOW – V
TYP
1.4
1.2
1.0
0.8
0.6
0.4
0.2
5
4
3
2
1
0
0
0.5
1
1.5
OUTPUT CURRENT (A)
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
OUTPUT CURRENT – A
Figure 2. Typical sink saturation voltages vs. load
current
Figure 4. Typical power dissipation vs. output
current.
UNITRODE CORPORATION
7 CONTINENTAL BLVD. • MERRIMACK, NH 03054
TEL. 603-424-2410 • FAX 603-424-3460
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