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5v 5 V holdup/ temporary backup circuit

I have a project where I'm using an android tablet to power a serial relay, the relay is 20m20 m from the tablet so iamI'm using a UsbUSB C > UsbUSB A hub and a self powered USB over cat6CAT6 extender. When the tablet is charging through the input in the usbUSB hub all is well. However when I turn the charger off (which needs to happen from time to time) there's a small <1s<1 s delay between the supply power switching from charger to tablet battery and my relay turns off. Would it be possible to add a capacitor or super capacitor to the circuit after the hub to keep the voltage up on the extender and relay board during changeover? 

I found this thread:

Car bluetooth power delay- USB capacitor?

With this diagram enter image description here

I have found that I can get a 1 faradF 5.5v5 V supercap for a reasonable price, would this circuit be enough, it seems too simple and I don't want to damage anything with over voltage or overcurrent.

Thanks in advance

Tim

5v holdup/ temporary backup circuit

I have a project where I'm using an android tablet to power a serial relay, the relay is 20m from the tablet so iam using a Usb C > Usb A hub and a self powered USB over cat6 extender. When the tablet is charging through the input in the usb hub all is well. However when I turn the charger off (which needs to happen from time to time) there's a small <1s delay between the supply power switching from charger to tablet battery and my relay turns off. Would it be possible to add a capacitor or super capacitor to the circuit after the hub to keep the voltage up on the extender and relay board during changeover? I found this thread

Car bluetooth power delay- USB capacitor?

With this diagram enter image description here

I have found that I can get a 1 farad 5.5v supercap for a reasonable price, would this circuit be enough, it seems too simple and I don't want to damage anything with over voltage or overcurrent.

Thanks in advance

Tim

5 V holdup/ temporary backup circuit

I have a project where I'm using an android tablet to power a serial relay, the relay is 20 m from the tablet so I'm using a USB C > USB A hub and a self powered USB over CAT6 extender. When the tablet is charging through the input in the USB hub all is well. However when I turn the charger off (which needs to happen from time to time) there's a small <1 s delay between the supply power switching from charger to tablet battery and my relay turns off. Would it be possible to add a capacitor or super capacitor to the circuit after the hub to keep the voltage up on the extender and relay board during changeover? 

I found this thread:

Car bluetooth power delay- USB capacitor?

With this diagram enter image description here

I have found that I can get a 1 F 5.5 V supercap for a reasonable price, would this circuit be enough, it seems too simple and I don't want to damage anything with over voltage or overcurrent.

Thanks in advance

Tim

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Tim
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5v holdup/ temporary backup circuit

I have a project where I'm using an android tablet to power a serial relay, the relay is 20m from the tablet so iam using a Usb C > Usb A hub and a self powered USB over cat6 extender. When the tablet is charging through the input in the usb hub all is well. However when I turn the charger off (which needs to happen from time to time) there's a small <1s delay between the supply power switching from charger to tablet battery and my relay turns off. Would it be possible to add a capacitor or super capacitor to the circuit after the hub to keep the voltage up on the extender and relay board during changeover? I found this thread

Car bluetooth power delay- USB capacitor?

With this diagram enter image description here

I have found that I can get a 1 farad 5.5v supercap for a reasonable price, would this circuit be enough, it seems too simple and I don't want to damage anything with over voltage or overcurrent.

Thanks in advance

Tim