NJM3777
DUAL STEPPER MOTOR DRIVER
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GENERAL DESCRIPTION
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PACKAGE OUTLINE
The NJM3777 is a switch-mode (chopper), constant-current
driver with two channels: one for each winding of a two-phase
stepper motor. The NJM3777 is equipped with a Disable input
to simplify half-stepping operation. The NJM3777 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
NJM3777E3
diodes. Voltage supply requirements are + 5 V for logic and +
10 to + 45 V for the motor. Maximum output current is 900mA
per channel.
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FEATURES
鈥?Dual chopper driver
鈥?900 mA continuous output current per channel
鈥?Digital filter on chip eliminates external filtering components
鈥?Package
EMP24(Batwing)
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BLOCK DIAGRAM
Phase
1
Dis
1
V
R1
C
1
E
1
NJM3777
V
CC
V
鈥?/div>
+
CC
R
S
Q
M
A1
Logic
M
B1
V
MM1
+
鈥?/div>
V
MM2
M
B2
Logic
M
A2
RC
+
鈥?/div>
S
R
Q
Phase
2
Dis
2
V
R2
C
2
GND
E
2
Figure 1. Block diagram
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