TB67B000HG
2013-5-9
17
9. Motor-lock detection
When hall signal detects below state, intermitted operation (drive period: stop period = 1: 6) is repeated.
<Description of motor-lock detection>
Motor lock detection starts counting (drive period) when V
SP
exceeds 2.1 V. When direction of motor rotation
and setting direction are the same (forward direction: sine-wave PWM mode or wide-angle commutation
mode), lock detection drives with 120° commutation (square-wave drive) under the condition that frequency
of the hall signal is about 1 Hz or less (when f
osc
= 5MHz).
When direction of motor rotation is opposed against setting direction (reverse direction: 120° commutation
mode of reverse hall input), lock detection drives under the condition that frequency of the hall signal is
about 5 Hz or less (when f
osc
= 5MHz).
When lock detection enables, operation is turned off (output drive is OFF) during stop period.
When V
SP
is set 1.0 V or less, counter is reset and remove stop state. Then, when V
SP
is set 2.1 V or more
again, counter starts counting from initial state.
Table of lock detection
Vsp pin > 2.1V Vsp pin ≤2.1V
Direction of motor rotation
CW/CCW pin
CW CCW
-
High(CW) f
osc
≤ 1Hz
(Rotating direction:
set of CW/CCW pin = motor)
f
osc
≤ 5Hz
(Rotating direction:
set of CW/CCW pin ≠ motor)
Inactive
Low(CCW) f
osc
≤ 5Hz
(Rotating direction:
set of CW/CCW pin ≠ motor)
f
osc
≤ 1Hz
(Rotating direction:
set of CW/CCW pin = motor)
Inactive
<Setting method>
Time of detection and stop outputting can be determined by an external capacitor (C
1
) of TR pin.
･Setting period
Drive period Ton[s] =C1× (VH―VL) ×2/I×500 counts
Stop period Toff[s] =C1× (VH―VL) ×2/I×3000 counts (Note 1)
• Ex.: When C1 = 0.01μF, I = 3μA (typ.), VH= 2 V (typ.) and VL= 0.5V (typ.), and then Ton[s] =5s (typ.) and
Toff[s] =30s (typ.).
Note 1: Bootstrap capacitor does not charge (refresh) during stop period.
To charge bootstrap capacitor in recovery, Vsp should be set as follows by voltage command input; 1.0 V <
V
sp
<
2.1 V.
Note 2: When TR pin is open, the operation moves to stop mode (drive output OFF) by open detection.
Note 3: Counter is not activated by applying fixed voltage (GND) to the TR pin. And motor lock detection is turned off and
drive mode can be continued.
120° commutation →wide-angle commutation
120° commutation→sine-wave drive
(Hall > 1 Hz)
Hall U
Hall V
Hall W
Counter
Oscillation
Open detection
by TR pin
Counter reset
TR
Drive output
control
C
1
Counter start
Counter reset
Vsp
Vsp>2.1V
(Typ)
Vsp<1V
(Typ)
