tb6560aftg TOSHIBA Semiconductor CORPORATION, tb6560aftg Datasheet - Page 17

• Manufacturer Part Number: tb6560aftg
• Description: Pwm Chopper-type Bipolar Driver Ic For Stepping Motor Control
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Predefined
Current Level
Predefined
Current Level
Predefined
Current Level
10. Current Control Modes (Effects of Decay Modes)
Note: The above figures are rough illustration of the output current. In actual current waveforms, transient response
•
•
•
Increasing the current (sine wave)
Decreasing the current with a high decay rate (The current decay rate in Mixed Decay mode is the ratio
between the time in Fast-Decay mode (discharge time after MDT) and the remainder of the period.)
Decreasing the current with a low decay rate (The current decay rate in Mixed Decay mode is the ratio
between the time in Fast-Decay mode (discharge time after MDT) and the remainder of the period.)
current at the RNF (current monitoring point), the Charge mode in the next chopping cycle will
disappear (though the current control mode is briefly switched to Charge mode in actual operations for
current sensing) and the current is controlled in Slow and Fast Decay modes (mode switching from Slow
Decay mode to Fast Decay mode at the MDT point).
curves can be observed.
During Mixed Decay and Fast Decay modes, if the predefined current level is less than the output
Charge
Charge
Charge
Slow
Slow
Slow
Fast
Fast
Fast
Charge
Charge
Charge
Slow
Slow
Predefined
Current Level
Predefined
Current Level
Predefined
Current Level
Slow
17
Fast
Fast
Fast
Since the current decays quickly, it can be
decreased to the predefined value in a short time.
Since the current decays slowly, decreasing the current
to the predefined value takes a long time (or the current
cannot be properly decreased to the predefined value).
Charge
Slow
Slow
Slow
Fast
Fast
Fast
Charge
Charge
Slow
TB6560AFTG
Slow
2011-05-23
Fast
Slow
Fast
Fast