Hi, i tried seaching the forum and on google but i can't really find what im looking for..
im looking for a router that's powered via USB, with 4-5 (1 port wan) port switch. Like the OYE-0001 (but i don't think you can buy this router anymore?)
i know about the GL.Inet routers but it's only 2-3 ports.
br
That's going to be a challenge, due to power consumption and that a USB port can't be expected to provide more than 2.5 W (500 mA) of power.
The GL.iNet AR750S ("Slate") is perhaps the closest I've seen, with three Ethernet ports. It peaks at around 750 mA during boot with two Ethernet cables active, both radios on, but no wireless clients.As such, I wouldn't run it off a USB 2.0 port, but only a USB-style, 5 V adapter (or a port that I was 100% sure could provide at least 1 A).
Adding an Ethernet client isn't free. In my experience, it added ~40 mA to the power draw on the AR300M-Lite. Multiply that by 5 and you're at 200 mA. That's on top of whatever the CPU consumes under full load, as well as the power to drive the radios. Oh, then you need the power to drive the switch functionality within the SoC.
Is there a reason why running off a 12 V supply isn't viable to you?
Use of a 12 V primary supply allows the current to drop and the voltage / power loss in the leads to be reduced.Six feet of 26 AWG is ~0.25 Ω on each leg, so at 500 mA and you're only seeing ~4.75 V at the device. Raise that to 1000 mA and you're losing 10% of your power to heating up the power lead.
Indeed, you can expect 1-1.5 watts per (active) 1000BASE-T port, which is more than USB 2.0 can provide for 4+1 ports alone (ignoring the power requirements for the SOC and wlan cards).
http://www.ti.com/lit/an/snla089b/snla089b.pdf
Section 4.4 shows around 300 mW for 10/100 speeds at 3.3 V, so you're probably looking at ~400 mW off a 5 V supply (due to converter inefficiencies). 5 ports at 400 mW = 2 W of your 2.5 W limit right there.
Yes, 100BASE-T needs significantly less power than 1000BASE-T, but 5 V/ 500 mA puts a quite low limit on the number of ethernet ports (or other functionality, e.g. dual-band).
thank you for the answers.
The application im going to use this router(s 15-20pcs) for do not require any wifi. The only thing this router is going to do is communication between two subnet.
i know that 12v would be better to use but there's only usb or 24 v available. I could use a 24v to 12v step down adapter, do anyone know a good adapter with dc plug in the 12v end? Or maybe a router that's not to expensive that runs on 24v?
Have you considered 24V Power over Ethernet POE.
Yes, but then i need to add a poe 24v injector, but i havent found any router that support 24v poe with 4 ports.. only wireless cpe. Another way to it is using 24v injector then an active 24v to 12v poe splitter.
First i was thinking of using passive poe adapters to power the router from another location.. But the network cables that is being used only got 4 wires, not 8 
Mikrotik hEX s for example can use passive poe with 24V. But it does not have OpenWrt, I'm not sure wheter that is required for you.
Note: These datatable are big (wide) -> look at the second last column "Power supply". The datatables are sorted by this column so you can easily identify which input voltage range suits you best.
Mikrotik has some wide-range input devices.
There was a recent thread on the Ubiquity EdgeRouter X that suggests it might be worth looking at for your application. It's under US$60
Interestingly, and you'd want to confirm with the manufacturer or manual, from https://store.ui.com/products/edgerouter-x, it might run off 24 VDC directly.
From 24 VDC to 12 V, a switching regulator (as opposed to a linear regulator) should be reasonably inexpensive for the output current required. As I recall, the LM2596 is moderately efficient (~70%), but the XL4015 and similar are around 90%. Small boards capable of 3 A of output are available through auction / import sites for about US$1 each. Check the specs of the chip used as some won't handle 24 V input (such as the MP1484).
