LB11981 Datasheet, PDF (5/7 Pages) Sanyo Semicon Device – Three-Phase Sensorless Motor Driver

LB11981
Truth Tables
Pin 4 (LAT): Lock detection circuit mode switching
LAT
OPEN
“L”
Mode
Automatic recovery mode
Output latched in the off state when lock detected.
Pin 5 (INFR): Motor rotation direction switching
INFR
OPEN or “L”
“H”
Mode
Forward
Reverse
Pin 3 (LKC): Lock detection time setting capacitor connection
LKC
GND
Capacitor inserted
Mode
Disabled
Enabled
Pin 6 (LKO): Lock state detection signal (A pull-up resistor is required.)
LKO
“H”
“L”
State
Lock not detected
Lock detected
Lock Detection Time Setting (automatic recovery mode)
[LKC pin]
4V
2V
t1
t2
t3
Output off period
Start of lock detection
ILB00050
The following formula gives the time, t1, from the point the motor speed is locked until the output is turned off.
t1[s] = C [µF] × 4 [V] / 1 [µA]
The output off time, t2, is as follows.
t2[s] = C [µF] × 2 [V] / 0.65 [µA]
The time, t3, following the output off state until the motor speed locked state is monitored, is as follows.
t3[s] = C [µF] × 2 [V] / 1 [µA]
When pin 4 (LAT) is low (output off latching mode), after the t1 period lock state monitoring, the output is turned off
and the output is held in the off state until either the V_CC or V_CCM power supply is switched.
No. 6656-5/7