I have recently added two usb ports on my new Prius 2013. Here are some pictures. first, take out the plate. the trick is to insert a plastic card into the bottom seam and pry. then I found a old USB bracket for computer. there were two mounting screws. drill holes using the metal USB bracket as template. I got a DC-DC LM2596 converter from eBay, ~$2. solder the usb wire (red to positive, black to negative/ground) to the output pads of the converter. then solder two wires to connect to the 12V adapter. I use solder the negative/ground to the outside shell of the adapter. Then adjust the voltage to 5.1V. It works fine. the things need improving are my Dremel skills, it should look better. The wire on USB bracket has very small gauge, maybe less than #22. If you can find one with larger gauge, it will supply better current for charging. LM-2596 supports up to 2A without heat sink.
Same idea, just different location and purpose. For charging I use a lighter plug adapter like above.
I like the option of having a high current USB port to charge a smart phone and leave the accessory jack for the GPS or fridge or inverter for the wife's laptop Mike
this would be nice too Toyota Prius ZVW30 35 USB Port Mobile Charger Mobile Audio Connection JDM | eBay
Why not just use a 12V adapter? The reason is just to save the 12V port to GPS or another phone... Most cheap adapter cannot support the current they claim they can do, like 1A. They generate a lot of heat under load as their efficiency is low. LM-2596 is a switch-type DC-DC converter, >85% efficiency, with over-current, over-heat, short-circuit protection. Another reason is my HP touchpad need 5.1V to be charged.
I installed a USB port in the same place and using the same Buck Converter as Huan. But I had to built it to Apple specs. I hate Apple, but I love my son, and he likes Apple. So I got tired of all the power requirements for phones, gps, etc. So I gave my son his own 2A USB port built to Apple specifications. It was actually fairly easy. Since Apple has to be different it has a power checking circuit built in to its devices. The circuit uses the D+ and D- pins in the USB connector. It detects 2.8v on D- and 2v on D+ to get 1A charge. Or 2.8v on D+ and 2v on D- to get 2A charge. Anything different will only give the device 500mA charge. So I wired it with a voltage divider to get 2A charge. I hate Apple. The whole thing, DC-DC Buck Converter and resistors cost less than $6, usb female panel connector $6, and three Apple 5 clone USB power cables cost $9, totaling $21 worth of parts off ebay, delivered. Apple sucks! DC-DC Buck Converter is the circuit board in the center with the blue voltage trimmer. The voltage divider made of four resistors is on the far right at the end of the black cable. USB port on left, 12v power supply next to it, and the black rectangular connector on the right are my seat warmer switches.
Nice work Gliderman. Yes, Apple sucks. I hate them too. How about posting a schematic of the circuit and a parts list? SCH-I535
Here is a diagram of the USB charger and parts list: Female USB Panel connector 51k Resistor x2 75k Resistor 43k Resistor DC-DC Buck Converter trimmed to 5.2V Standard USB Charger is on left. APPLE spec USB Charger is on right.
Thanks for the link. Those are audio ports. I just wanted a charging port. They must be coming from Japan with those shipping prices. Otherwise shipping is a big ripoff.
