NJM3775
DUAL STEPPER MOTOR DRIVER
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GENERAL DESCRIPTION
The NJM3775 is a switch-mode (chopper), constant-
current driver with two channels: one for each winding
of a two-phase stepper motor. NJM3775 is equipped
with a Disable input to simplify half-stepping operation.
The NJM3775 contains 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, including recirculation diodes.
Voltage supply requirements are + 5 V for logic and +
10 to + 45 V for the motor. Maximum output current is
750mA per channel.
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PACKAGE OUTLINE
NJM3775D2
NJM3775E3
NJM3775FM2
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FEATURES
• Dual chopper driver
• 750 mA continuous output current per channel
• Digital filter on chip eliminates external filtering components
• Packages
DIP22 / PLCC28 / EMP24(batwing)
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BLOCK DIAGRAM
Phase
1
Dis
1
V
R1
C
1
E
1
NJM3775
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