EDN

Short push, long push for sequential operation of multiple power supplies

In MCU-based projects, this design uses a single push button to switch on and switch off 5-V and 15-V supplies in sequence.
EDN

Push-Button Circuit

This push-button circuit can be used with a wide variety of PMICs. For example, this circuit can be used to drive a control pin, which enables and disables the buck converters, for the TPS65086 device ...
Electronics Weekly

K. Whittingham’s cunning push button circuit

“Why not use a D-Flip Flop with the switch connected to clock, and via an RC to the Data input. Release switch quickly data is still low so output low. release after RC charged data is high so output ...