tb62214ftg TOSHIBA Semiconductor CORPORATION, tb62214ftg Datasheet - Page 14

• Manufacturer Part Number: tb62214ftg
• Description: Bicd Constant-current Two-phase Bipolar Stepping Motor Driver Ic
• Manufacturer: TOSHIBA Semiconductor CORPORATION

predefined current level, the internal RS comparator detects the predefined current level (NF); as a result, the IC
enters Slow-Decay mode.
frequency (one chopping frequency) remains in a whole PWM frequency period (on the rising edge of the 11th
clock of the OSCM clock).
counter is reset, which brings the TB62214FG/FTG into Charge mode again.
Note: These figures are intended for illustrative purposes only. If designed more realistically, they would show
Current Waveform in Mixed (Slow + Fast) Decay Mode
Timing charts may be simplified for explanatory purposes.
The Charge period starts as the internal oscillator clock starts counting. When the output current reaches the
The TB62214FG/FTG transits from Slow-Decay mode to Fast-Decay mode at the point 37.5 of a PWM
When the OSCM pin clock counter clocks 16 times, the Fast-Decay mode ends; and at the same time, the
When a current value increases (Mixed-Decay point is fixed to 37.5%)
When a current value decreases (Mixed-Decay point is fixed to 37.5%)
current level
OSCM CLK
Predefined
current level
OSCM CLK
Predefined
Internal
transient response curves.
Internal
Charge
Charge
NF
NF
Slow
Slow
f
f
chop
chop
Fast
Fast
Charge
Charge
NF
NF
Slow
Slow
f
f
chop
chop
current level
Predefined
current level
Predefined
14
Fast
Fast
Charge
The IC enters Charge mode for a moment at which
the internal RS comparator compares the values.
The IC immediately enters Slow-Decay mode
because of the current value exceeding the
NF
Charge
NF
Slow
f
Slow
f
chop
chop
Fast
Fast
TB62214FG/FTG
Charge
NF
Charge
NF
Slow
Slow
f
f
chop
2010-06-10
chop
Fast
Fast
NF
Charge