NJM37770D9 New Japan Radio Co., Ltd., NJM37770D9 Datasheet - Page 3

• Manufacturer Part Number: NJM37770D9
• Description: Motion Motor Control, 5V Operating Voltage, -40C to 150C Operating Temperature, DIP
• Manufacturer: New Japan Radio Co., Ltd.

The NJM37770 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
to M
B
and low input from terminal M
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 µs/div.
M
),
NJM37770