onsemi PMM5320-E

Stepping motors are finding greater use not only in semiconductor manufacturing equipment, but also in such things as office automation equipment and food preparation equipment. This is mainly due to the ease of open loop control and the low system cost of stepping motors.

• The use of smaller parts, better integration, and reduction of the size of the heat sink due to decreased heat generation from the power module has allowed a 68% reduction in size and a 57% reduction in weight over conventional models.
• The two - phase unipolar lines had a disadvantage in damaging the driver from an open phase, but the product we have developed detects open phases and protects against them while outputting an alarm and lighting an LED. The two - phase bipolar driver and five - phase pentagonal driver have similar functions.
• In addition to wiring with conventional connectors, we have also created a wiring system that uses the terminals. Wiring can now be done without the need for a special crimp tool. As with conventional products, the photocoupler type and the C - MOS type are available as the input/output interface.
• The control circuit and the main circuit both use long life electrolytic capacitors. The lifetime of the electrolytic capacitor used in the control circuit is 2000 hours at 105°C for the conventional product but 5000 hours for the new product. The lifetime of the electrolytic capacitor used in the main circuit is 5000 hours at 105°C for the conventional product but 10000 hours for the new product. By reducing the heat generated by the power module, the ambient heat of the electrolytic capacitor is also reduced, leading to a lifespan twice that of the conventional product.
• The two - phase unipolar and bipolar drivers each have a micro - step function. Resolution can be set to one of five levels, from 1/1 to 1/16, with the DIP switch. Additionally, with low vibration mode on, even coarse settings such as 1/1 or 1/2 can proceed smoothly with micro - step operation.
• The five - phase pentagonal driver uses a new PWM control method. The conventional product had a maximum on duty PWM of 70%. This has been raised to 100% in the new product. Switching to this new control method allowed for an increase in output torque in high speed areas. Additionally, the conventional five - phase pentagonal product consumed more drive current than necessary in medium speed areas, causing vibrations. The new product uses a different excitation method to solve this problem.