ZHCSJW0D June 2019 – March 2020 TPS62840
To avoid a floating input, an internal 450-kΩ resistor pulls the EN pin to GND. This prevents an uncontrolled start-up of the device in case the EN pin cannot be driven low safely. The device is in shutdown mode when the EN input is logic low.
The device turns on with a logic high EN signal. An internal control circuit disconnects the EN pin pulldown resistor once the device has finished soft start and the output voltage is in regulation. With the EN pin set low, the device enters shutdown mode and the pulldown resistor is activated again.