Specification

[AP1034]
016003455-E-01 - 18 - 2016/06
 Over Current Protection Circuit (OCP)
The IC has over current protection circuit to prevent breakdown of H-Bridge drivers. If the specified current
flows, H-Bridge outputs of all channel becomes latch off. It recovers by re-input of the motor power supply
voltage (VM) or input of SLEEPB or RESETB.
VOUT
ON
IOUT
I
OCPTRIP
t
OCPDET
SLEEPB or RESET
B
OFF(HI-Z)
OFF(HI-Z)
t
OCPDET
VM
Figure 13. OCP Timing Chart
Note13. If latch is released under the abnormal condition after OCP operation, the IC may repeat the
operation(latch → return → latch) . This will be the cause of heat generation and deterioration of the IC.
Also, chattering noise on SLEEPB or RESETB pin may cause a malfunction of OCP and it will result in
damage to the device.
Note14. When the Shorted-Load or the Shorted-to-Power occurs, the current comparison comparator works.
After the blanking time, the IC becomes slow decay mode and repeats normal operation every chopper cycle.
Note15. If the current sense resistors(R
IS
) are shorted, the OCP operates before the current comparator
comparison works in all conditions, so that the output of all channels will be Hi-Z.