有源增益控制 Active gain control（AGC）使用一種簡單的技術來解決此問題，從而提高了產品的價值。
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Toshiba offers an extensive lineup of stepping motor drivers fabricated using a BiCD process that provides high accuracy and high-current capability. Toshiba's stepping motor drivers are available in bipolar and unipolar configurations.
Toshiba's original ADMD technology tracks input current more closely than the conventional mixed-decay mode, making highly efficient motor control possible at high rpm.
Toshiba's original ACDS technology enables motor drive with highly accurate constant current without requiring external current-sensing resistors.
The reduced part count also helps reduce the board area and the bill-of-material (BOM) cost.
To provide sufficient margin for the motor torque required, motor control drivers (MCDs) generally supply a motor drive current greater than the peak current at the maximum load. This means that extra current continues flowing all the time. In order to minimize unnecessary current consumption, a sensor or a microcontroller is used to monitor the changes in load conditions, thereby adjusting a motor drive current according to the load conditions. This feedback process requires extremely complicated control. Toshiba offers motor driver ICs incorporating AGC technology, which sense a motor's load torque and automatically optimize a motor drive current. This makes it possible to prevent a motor from going out of step while simplifying high-efficiency motor control.
AGC technology automatically adjusts a motor drive current according to a motor's load conditions in order to reduce extra current, thereby considerably reducing the amount of heat generated by the motor driver IC and the motor. This helps reduce overall heat generation in a system and the resulting degradation.
The step angle is 360 degrees divided by the total number of poles.
For the four poles, 360 degrees/4 = 90 degrees.
Assuming there is a 36-pole motor, 360 degrees/36 = 10 degrees, and the single-step operating angle of the full-step mode is 10 degrees.
One step angle of the half-step mode is 1/2 of the full-step mode.
One step angle of the micro-step mode can be selected to be 1/4 of the full-step mode and a finer step angle.
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