NJM3770A
STEPPER MOTOR DRIVER
s
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.
s
PACKAGE OUTLINE
NJM3770AD3
NJM3770AE2
s
EATURES
鈥?Half-step and full-step operation
鈥?Switched mode bipolar constant current drive
鈥?Wide range of current control 5 -1800 mA
鈥?Wide voltage range 10 - 45 V
鈥?Thermal overload protection
鈥?Packages DIP16 (Batwing) / PLCC28 / EMP20
NJM3770AFM2
s
BLOCK DIAGRAM
V
CC
Schmitt
Trigger
Time
Delay
V
MM
V
MM
Phase
I
1
1
鈮?
鈮?
M
A
I
0
V
R
M
B
&
+
鈥?/div>
+
鈥?/div>
+
鈥?/div>
GND
&
&
&
鈮?
鈮?
Output Stage
Monostable
t
off
= 0.69 鈥?R
T
鈥?C
T
Current Sensor
NJM3770A
C
T
E
Figure 1. Block diagram
next