Simple retriggeable delay circuit for an USB outlet

Our new TV has a funny weird way of turning the USB power on and off during power on and when entering stand-by. As I use the 5V power signal from of one USB outlets to control the loudspeaker amplifier, I made a small delay circuit to get a stable USB control signal.

When the TV-USB get 5V DC from the TV USB connector, C1 is (quickly) charged via R1 making the output of the comparator IC1A going low to open Q1 to apply a stable 5 V power signal at the X1 USB connector.

The time constant C1 * R2 provides enough delay to cope with the funny on/off sequences of the TV 5V USB powersupply 🙂