an44060a Panasonic Corporation of North America, an44060a Datasheet - Page 25

• Manufacturer Part Number: an44060a
• Description: Ic For Stepping Motor Drives
• Manufacturer: Panasonic Corporation of North America

AN44060A
Usage Notes
(continued)
A high current flows into the IC. Therefore, the common impedance of the PCB pattern cannot be ignored. Take the following
points into consideration and design the PCB pattern of the motor.
A high current flows into the line between the VM1 (pin 8) and VM2 (pin 22) pins. Therefore, noise is generated with ease at the
time of switching due to the inductance (L) of the line, which may result in the malfunctioning or destruction of the IC (see the
circuit diagram on the left-hand side). As shown in the circuit diagram on the right-hand side, the escape way of the noise is secured
by connecting a capacitor to the connector close to the VM pin of the IC. This makes it possible to suppress the direct VM pin
voltage of the IC. Make the settings as shown in the circuit diagram on the right-hand side as much as possible.
Low spike amplitude
due to
Noise is generated with ease
Recommended PCB
the capacitance
between
the VM pin and ground pin
VM
VM
L
L
IC
IC
C
C
GND
GND
SFA00002AEB
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