555 timer question & "Bounceless" Garage door opener. When opening a garage door from a distance, it is sometimes necessary to push the button multiple times when beyond the range of the transmitter. One can inadvertnently push the button multiple times and cancel the door going up. To open the door, one must push the button three more times to go down, cancel, and go up. I resolved to solve this problem. I built a "bounceless" switch with a 555 timer and a relay. There are 3 leads going between the motor and radio receiver. 24 VAC, Common, and "relay". The radio receiver grounds the "relay" lead to signal the motor to close the door. All I needed to do was interrupt the "relay" leg. For my bounceless switch, the "relay out" of the radio receiver grounds the input of a 555 timer. The output of the 555 timer closes a contractor connected to "relay in" on the opener motor. I chose a resistor and capacitor that make the 555 hold the output down for about 4 seconds. Now, if I inadvertently hit the button multiple times, the motor does not receive multiple open signals because the 555 is still "holding down" the button. Here are the voltage requirements of my components. Components 555 Chip - 4.5 to 15 VDC. Relay - 9 VDC Here are my available voltage sources 24 VDC in radio receiver 8 VDC in radio receiver. 17 VDC repurposed transformer. Initially, I was hoping the 8VDC would be enough to close the relay, but it was not sufficient. Currently, I have the 17 VDC source powering both the chip and relay. Ok. Finally my question. Am I OK to have both the chip and relay powered by the 17 VDC source? The relay is on for only 4 seconds, so I'm not that worried about that burning up. The chip has a large input impedance, so it should be comfortable with 17 VDC. Is the 555 forgiving enough that I could even use the 24 VDC from the radio receiver? This would be a much more elegant solution.