Other Parts Discussed in Thread: BUF634
Question on BUF634 Current limit Characteristic.
According to the Datasheet of BUF634, it is said that BUF634 has internal current limit protection circuit equiped inside the chip. However, I wander if this internal current limit circuit works well. Pls explain the characteristics of the current limit function of the BUF634. What if BUF634 is put into continuous short circuit condition. Does this part survive in this condition.
Hi Wook,
As mentioned in the Application Section of the datasheet, the internal current limit protection circuit in short circuit condition limits the output current depending upon the junction temperature of the device.
Also, depending upon the ambient temperature and power dissipated in the device (due to output current) in short circuit condition, the junction temperature(Tjc) might increase and, at 175'C Tjc the thermal protection kicks in disabling the outputs. As the device cools subsequently to below 165'C Tjc, the outputs are enabled again. So, the part will survive continous short circuit condition. However, for long term reliability, it is recommended to limit the junction temperature to within 150'C.
Best Regards,
Rohit
