NJM3770AFM2 NJR, NJM3770AFM2 Datasheet - Page 3

• Manufacturer Part Number: NJM3770AFM2
• Description: IC STEPPER MOTOR DRIVER 28-PLCC
• Manufacturer: NJR
• Type: Stepper Motor Controller/Driverr

Specifications of NJM3770AFM2

• Applications: Stepper Motor Driver
• Number Of Outputs: 1
• Current - Output: 1.5A
• Voltage - Load: 10 V ~ 40 V
• Voltage - Supply: 4.75 V ~ 5.25 V
• Operating Temperature: -20°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 28-PLCC
• Product: Stepper Motor Controllers / Drivers
• Operating Supply Voltage: 6 V
• Supply Current: 40 mA
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

The NJM3770A is intended to drive a bipolar constant current through one winding of a 2-phase stepper motor.
• Input logic
• Current sense
• Single-pulse generator
• Output stage
Input logic
Phase input
The phase input determines the direction of the current in the motor winding. High input forces the current from
terminal M
circuit eliminates the risk of cross conduction in the output stage during a phase shift.
Current control is achieved through switched-mode regulation, see figure 3 and 4.
Three different current levels and zero current can be selected by the input logic.
The circuit contains the following functional blocks:
Half- and full-step operation is possible.
FUNCTIONAL DESCRIPTION
Figure 3. Output stage with current paths
for fast and slow current decay.
A
Motor Current
to M
B
and low input from terminal M
Fast Current Decay
Slow Current Decay
2 1
3
External recirculation
diodes
1
R
S
2
3
Time
B
to M
A
. A Schmitt trigger provides noise immunity and a delay
Figure 4. Motor current (I
Vertical : 200 mA/div,
Horizontal: 1 ms/div,
expanded part 100 s/div.
0
200 mA/div
M
),
NJM3770A
1 ms/div
100 s/div