CD4538B Rapid Power Down Protection Circuit Diagram and Datasheet
CD4538B Rapid Power Down Protection Circuit Diagram and Datasheet -There is a rapid power-down condition when a power supply short circuit or when there is a poorly filtered power supply.
CD4538B series CMOS Dual Precision Monostable Vibrator has the Power-Down Mode feature to avoid possible device damage in this mode.
As seen in the circuit diagram, in such mentioned condition above, the energy stored in Cx could discharge into Pin 2 or 14 of the CD4538B IC.
In order to avoid device damage when Cx is bigger than 0.5uF, a 1A or higher (1N5395 or equivalent) of protection diode and a separate ground return for Cx should be provided.
See the CD4538B datasheet for completed CD4538B Rapid Power Down Protection Circuit Diagram (source: littlediode.com).
Tags: CD4538B datasheet, power down circuit, power protection circuit,