I want to enable/disable a TI TPS54302 buck regulator with a microcontroller. The enable (EN) pin should float to enable the device, or be tied low to disable it.
I currently have the EN pin connected to a GPIO pin on the MCU. At startup, before the pin state can be set low, it will sometimes already be floating, so the regulator operates for a brief time before the pin is intentionally set low.
I'd like to add an external pull-down resistor to ensure the regulator stays off until it is supposed to be on, but that would prevent floating the pin.
I presume I could simply pull the pin high (instead of floating it) and achieve the desired result. The TPS54302 datasheet says:
The EN pin has an internal pullup-current source which allows the user to float the EN pin to enable the device. If an application requires control of the EN pin, use open-drain or open-collector output logic to interface with the pin.
If I tie the EN pin to ground with a 10kΩ resistor, and pull the MCU pin high when I want the regulator to operate, is that a viable solution?
I'm not concerned about small (≥1mA) constant current usage as this is a line-powered device.