NJM3774
DUAL STEPPER MOTOR DRIVER
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GENERAL DESCRIPTION
The NJM3774 is a switch-mode (chopper), constant-
current driver with two channels: one for each winding of a
two-phase stepper motor. The NJM3774 is equipped with a
TTL level compatible Disable input to simplify half-stepping
operation. The circuit is well suited for microstepping
applications together with the matching dual DAC
NJU39610. In full/half stepping applications, the NJM3517
can be used as a phase generator (translator) to derive the
necessary signals for the NJM3774. The NJM3774 con-
tains a clock oscillator, which is common for both driver
channels, a set of comparators and flip-flops implementing
the switching control, and two output H-bridges. Voltage
supply requirements are +5 V for logic and +10 to +45 V for
the motor. Maximum output current is 1000mA per channel.
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PACKAGE OUTLINE
NJM3774D2
NJM3774FM2
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FEATURES
• Dual chopper driver
• 1000 mA continuous output current per channel
• Specially matched to the Dual DAC NJU39610
• Packages
DIP22 / PLCC28
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BLOCK DIAGRAM
Phase
1
Dis
1
V
R1
C
1
E
1
NJM3774
V
CC
V
–
+
CC
R
S
Q
M
A1
Logic
M
B1
V
MM1
+
–
V
MM2
M
B2
Logic
M
A2
RC
+
–
S
R
Q
Phase
2
Dis
2
V
R2
C
2
GND
E
2
Figure 1. Block diagram
NJRC [ NEW JAPAN RADIO ]
