5v 2A current limiter

[jms1989]

Hello, I'm looking to make a little usb power supply for my truck, I want to supply 4 usb plugs and my gps from a 5v 10A DC to DC step down. I would like to restrict each plug/device to 2A each with maybe some short circuit protection. How would I go about this and keep it as simple as possible. I don't have the greatest grasp on building electronics. Otherwise, I may have to find some 2A converters that are already current limited and just supply each one separately. The gps's car adaptor is rated at 1.7A I believe or close to it. If it can be built with little to no heat generation and cheaply, that'd be ideal.

 

[bill66656]

But for USB, the max current is 0.5A, and not 2A.

 

[jms1989]

I'm not following the standard and neither do all tablets and smart phones these days. tablets will not charge, if any, on 500ma. they need at least 1.5A. this is a standalone power supply that'll be running off my truck's 12V system thru a DC to DC step down of course. I'm only asking this so I can guarantee 2A per device and if needed, I'll make some splitters to divide that 2A for 2 1A or 4 500ma. I'll use the standard plugs but be providing a lot more current.

 

[goldsmith]

Hello, I'm looking to make a little usb power supply for my truck, I want to supply 4 usb plugs and my gps from a 5v 10A DC to DC step down. I would like to restrict each plug/device to 2A each with maybe some short circuit protection. How would I go about this and keep it as simple as possible. I don't have the greatest grasp on building electronics. Otherwise, I may have to find some 2A converters that are already current limited and just supply each one separately. The gps's car adaptor is rated at 1.7A I believe or close to it. If it can be built with little to no heat generation and cheaply, that'd be ideal.

Hi JMS 1989 !
If you're not experienced in electronics you can easily use fuses through your power lines to protect your supply from over current . but if you're experienced you can use a simple hiccup limiter ( based on a mosfet and a simple opamp )
Best Wishes
Goldsmith

 

[jms1989]

the problem with fuses is they tend to be one time devices, there's no reset if they blow. they'd have to be replaced. my goal is to replicate what a computer does by limiting each port to 500ma, I'm wanting to quadruple that to 2A. it doesn't have to be safisicated, just smart enough to cap out the current at a set value. What is a hiccup limiter and how does it work?

 

[PedroDaGr8]

A variety of companies make integrated IC's at various amperages many are designed for USB in particular.


For example:
TI: TPS2064 Dual 2.1A USB Current Limit
Maxim: 250mA to 2.5A adjustable current limit switch
Micrel: **broken link removed** 2A Current Limit Switch


You get the idea. There are a lot more from pretty much every company (Linear, NXP, Infineon, etc.)

 

[goldsmith]

he problem with fuses is they tend to be one time devices, there's no reset if they blow. they'd have to be replaced. my goal is to replicate what a computer does by limiting each port to 500ma, I'm wanting to quadruple that to 2A. it doesn't have to be safisicated, just smart enough to cap out the current at a set value. What is a hiccup limiter and how does it work?

Hi again
There are many types of reset able fuses available . but of course a hiccup current limiter will be so fine too .
Here a simple hiccup current limiter comes :


I've designed it for 2 amperes .

Best Wishes
Goldsmith

 

[babatundeawe]

hi goldsmith,

how can someone ensure that the circuit should not take more than the regulated current. take for instance if its drawing more than the limited current how can one make a circuit dat will regualte it and keep the current within limit without interrupting the circuit (that is stoping the circuit)

i hope i am clear enuf. can it self regulate the current if its going higher than the limit?

thanks