njm6219 New Japan Radio Co.,Ltd, njm6219 Datasheet - Page 7

• Manufacturer Part Number: njm6219
• Description: Njm6219 Stepper Motor Driver
• Manufacturer: New Japan Radio Co.,Ltd

■ FUNCTIONAL DESCRIPTION
Input logic
Phase input
M
the risk of cross conduction in the output stage during a phase shift.
Current level selection.
selected according to the table below.
A
Zero current
The NJM6219 is intended to drive a bipolar constant current through one winding of a 2-phase stepper motor.
Current control is achieved through switched-mode regulation, see figure 4 and 5.
Three different current levels and zero current can be selected by the input logic.
The circuit contains the following functional blocks:
● Input logic
● Current sense
● Single-pulse generator
● Output stage
The phase input determines the direction of the current in the motor winding. High input forces the current from terminal
Half- and full-step operation is possible.
The status of I
Motor current
High level
Medium level
Low level
to M
B
and low input from terminal M
0
and I
Figure 4. Motor current (I
Vertical : 200 mA/div,
Horizontal: 1 ms/div,
expanded part 100 µs/div.
100%
60%
20%
0%
1
inputs determines the current level in the motor winding. Three fixed current levels can be
I
L
H
L
H
0
I
L
L
H
H
1
B
to M
M
A
),
. A Schmitt trigger provides noise immunity and a delay circuit eliminates
Motor Current
Figure 5. Output stage with current
pathsfor fast and slow current
decay.
Fast Current Decay
Slow Current Decay
Rs
NJM6219
Time
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