ON / OFF switch of multiple signals - Page 1
Forum section: electronics / beginners

author: Godzilla
author_rank: Contributor
timestamp: June 28, 2021, 05:17:54 pm
content: Hello guys, im trying to make a remote switch for an USB C device, but since the usb C connector has 4 V+ pins and many other ground and signal pins i was wondering if theres a way to switch ON and OFF many signals at the same time, ive a bluetooth micro controller that has many pins that i can use, but i wanted to avoid using 10 MOSFETS or so, im pretty sure thare are other ways, do u have any ideas/suggestions?

author: bob91343
author_rank: Super Contributor
timestamp: June 28, 2021, 06:08:42 pm
content: One or more relays.

author: tooki
author_rank: Super Contributor
timestamp: June 28, 2021, 06:20:52 pm
content: Quote from: bob91343 on June 28, 2021, 06:08:42 pmNo way. They’re multi-GHz signals with strict signal integrity requirements. Running it through relays is likely to cause problems - not to mention that the signals need to be connected and disconnected in a specific order, which the USB connector enforces.There are USB load switches and whatnot, but if the OP has to ask, then they are practically guaranteed to not be able to implement USB-C.

author: Terry Bites
author_rank: Super Contributor
timestamp: June 28, 2021, 06:38:51 pm
content: There are usb to parallel chips, eg UM245R, they've got 8 data bits of output so you can control up to 256 devices. Add a 4>16 decoder like a CD4514. You'll need some kind of power switch on each line. How much current do you want switch at the remote end? Seach for high side switches as needed.

author: Godzilla
author_rank: Contributor
timestamp: June 29, 2021, 08:06:52 pm
content: Quote from: Terry Bites on June 28, 2021, 06:38:51 pmWell, waht i wanna do is make an overcharge protection tool for my phone, so i basically connect it to my phone and it communicates to it with bluetooth, my phone will send its charge status and if it reaches 80% i want to disconnect the charger, until it reaches 30% of charge again. The fact is that USB C has many control pins and im not exactly sure what i have to disconnect.

author: tooki
author_rank: Super Contributor
timestamp: June 30, 2021, 11:16:31 am
content: While maintaining a 50% charge is better for long term storage, let’s be clear that 100% isnot“overcharging”, and that you actually cannot overcharge it, since the charge controller in the phone stops charging when it’s done.Regardless, I thought Android had a setting to do this, so I don’t think you need to add any hardware.

author: Godzilla
author_rank: Contributor
timestamp: June 30, 2021, 12:07:07 pm
content: Quote from: tooki on June 30, 2021, 11:16:31 amI think i need root on my android to use app that set charge limit, also its not about overcharge is more about usury of the battery. For what i know charge the phone from 30 to 80% two times, should "damage" the battery less than charge it once from 0 to 100%...

author: BILLPOD
author_rank: Frequent Contributor
timestamp: June 30, 2021, 06:00:34 pm
content: Good Morning Godzilla, Just get a Mustool UD18. It operateson all USB forms and even has coax DC connectors. I use mine when charging my Samsung tablet. It has Bluetooth operation, which I've found is the easiest to operate it with. It will turn your devices off when your parameters are reached. I use the clock function and have it turn off after 5 hours, which works best for me. Also you could turn it off when a Milli-watthourtarget is reached, which you can set. It operates on 3.3 to 32VDC and up to 5.1 Amps. Check it out.

author: tooki
author_rank: Super Contributor
timestamp: June 30, 2021, 06:07:19 pm
content: Quote from: Godzilla on June 30, 2021, 12:07:07 pmAccording to whom?Bear in mind that “0%” in a properly designed device isn’t the battery’s true empty point. For example, in the battery I talk about earlier, the datasheet says to use 3.0V as the 0% state of charge, while the same datasheet otherwise lists 2.5V as the voltage it must never be taken below.