NJM3770A
STEPPER MOTOR DRIVER
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GENERAL DESCRIPTION
NJM3770A is a stepper motor driver, which consists of a
LS-TTL compatible logic input stage, a current sensor, a
monostable multivibrator and a high power H-bridge output
stage. The NJM3770A is a high power version and pin-
compatible with the NJM3717.Two NJM3770A and a small
number of external components form a complete control
and drive unit stepper motor systems.
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PACKAGE OUTLINE
NJM3770AD3
NJM3770AE2
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EATURES
• Half-step and full-step operation
• Switched mode bipolar constant current drive
• Wide range of current control 5 -1800 mA
• Wide voltage range 10 - 45 V
• Thermal overload protection
• Packages DIP16 (Batwing) / PLCC28 / EMP20
NJM3770AFM2
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BLOCK DIAGRAM
V
CC
Schmitt
Trigger
Time
Delay
V
MM
V
MM
Phase
I
1
1
≥1
≥1
M
A
I
0
V
R
M
B
&
+
–
+
–
+
–
GND
&
&
&
≥1
≥1
Output Stage
Monostable
t
off
= 0.69 • R
T
• C
T
Current Sensor
NJM3770A
C
T
E
Figure 1. Block diagram
NJRC [ NEW JAPAN RADIO ]
