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I know but I will say that the name is a bit misleading. Electronics includes everything from consumer to industrial, circuit level.
AskCircuitLevelElctronics , AskElectonicDesign maybe appropriate instead of using the Umbrella term of AskElectronics and then restricting it to only circuit level and electronic designs.
This is not any kind of aggression. Just my humble opinion.
Original usb ports often maxed out at 500ma. You probably won't need the second usb on a modern system, but you will need the 12v adapter. (usb maxes out at 5v)
Also, this is the wrong community.
So If I used 2 USBs (one for data and other for 500ma) + 12V/1A power supply, will it suffice my need of 5V/0.75A + 12V/0.75V?
you will need the 12v adapter
Not if there's something like a boost converter built in.
I don't know what you can draw from a modern USB port, but 12.75W is required by the drive, and when I tried a couple of months ago, I wasn't able to power a similar drive (it had a green and white label and was 1 TB, IDK what it was anymore) from a single USB-C port.
I'm curious, can you elaborate why you need this connector?
To answer your questions, those two USB A connectors are for power and data transfer, separately. But if you got a 3.5" drive, you're going to need that external 12V power supply anyway.
You can plug the data USB connector into the same PC to manage the files, but you can also put it in a different PC, so to transfer files between two devices quickly.
You can also use a power bank for the USB A power connector, but this will again only work with the 2.5" drives.
To transfer data from my old HDD to SSD.
So as per the other person's reply
Original usb ports often maxed out at 500ma.
So If I used 2 USBs (one for data and other for 500ma) + 12V/1A power supply, will it suffice my need of 5V/0.75A + 12V/0.75V?
I have something like the product you've found. Except mine has a single USB-C plug. My device can't power 3.5"HDDs nor optical drives. But it will power 2.5"HDDs and of course SSDs.
Your device has two USB plugs, one blue and another white. That the white plug is auxiliary power seems plausible. The USB standard specifies 0.5A max current per port. So two ports, 2.5W each, is 5W. 12V and 5V both 0.75A is 12.75W. So unless your computer has charging ports, capable of delivering extra current, it won't work.
The compact device is nice, when you're not working with 3.5" drives, but I have found the universal solution to be something with a separate SATA power connector, like this https://www.reichelt.com/dk/en/shop/product/usb_2_0_ide_sata_adapter_with_backup_function-88571?q=%2Fdk%2Fen%2Fshop%2Fusb-2-0-ide-sata-adapter-with-backup-function-logilink-au0006d-p88571.html&GROUPID=6196&OFFSET=16&r=1
It's bulky, but it works.
Thank You.
What If I used 2 USBs (one for data and other for 0.5A) + 12V/1A power supply, will it suffice my need of 5V/0.75A + 12V/0.75V?
So unless your computer has charging ports, capable of delivering extra current
Mine is a Laptop but it's adapter is 19V.
For the product you suggested, I'm looking for cheap products in terms of price.