Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Is it SAFE to connect a car battery to run a usb charging circuit?

Status
Not open for further replies.
S

Sunny55

Full Member level 3
Joined
Sep 15, 2012
Messages
159
Helped
12
Reputation
24
Reaction score
12
Trophy points
1,298
Activity points
2,404
I m using a car battery to run 2 usb chargers. There is a switching regulator circuit in between the battery n chargers to step dwn 12vdc to 5vdc and the 5vdc to power usb charger. That should be SAFE with such configuration ?

- - - Updated - - -

Is the switching regulator circuit sufficient to provide protection to the chargers or do i need fuse for protection or someother circuits? Pls help.
 

Sunny55 said:
I m using a car battery to run 2 usb chargers. There is a switching regulator circuit in between the battery n chargers to step dwn 12vdc to 5vdc and the 5vdc to power usb charger. That should be SAFE with such configuration ?

- - - Updated - - -

Is the switching regulator circuit sufficient to provide protection to the chargers or do i need fuse for protection or someother circuits? Pls help.
Click to expand...

Its safe until you start to carry that lead acid with you. :smile:

Problem which can occur is spikes and high ripples, that can overheat charger IC, and of course we have IC die hard scene. In that situation try to filter switcher output with additional filter for that design, for cheapest way first try to add 100nF ceramic capacitor.

By the way, you can use linear regulator for this also, such as 7805, 78S05, 78T05 or any other similar.

:wink:
 

sandipm14 said:
Use linear regulator as 7806, 78S05
Click to expand...

7806 is 6V regulator and for this is needed additional caution. Better check first max input voltage for charger. Lots chargers can support max up to 6V of input voltage, and some of them expect 5V from USB and support max 5,5V.

I supose you mistakenly type 6 instead 5 for 7805.

;-)
 

Hi there is already a switching regulator that converts the 12vdc to 5vdc to power the two chargers. Nw i m just worried of current spikes.
 

Sunny55 said:
Hi there is already a switching regulator that converts the 12vdc to 5vdc to power the two chargers. Nw i m just worried of current spikes.
Click to expand...

Maybe its quality product.

I see a great deal of concern, are you planning to charge Samsung Galaxy S4 with this?

Try to open voltage regulator device see what is inside, maybe you have just resistors. :oops::-(

Dont worry my friend every time when I see Chinese replicas inside I'm deeply shocked, but device works.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top