mgrande said:
MicroUSB cables are standard. Any quality cable will work. I got a 6-footer from Amazon to replace the pitifully short cable that comes with the phone. For that matter, any quality USB charger will work. The voltage is standard. Differences are in current output. The OEM chargers that come with the phone are 750-850ma, usually. The USB port on your computer typically will not put out that much current, nor will some car power adapters, so they may not charge as quickly, or may not charge at all while the phone is in use. However, beware of overly cheap chargers and cheap cables. If they are poorly made, they may not meet specs.
Suit yourself. Motorola makes several universal chargers of varying current rating that are razr compatible (for example, the p833 and p933). The key factor is voltage, not current, for Li type batteries, and that's managed by the charging circuitry on the phone. I'm using the Moto charger (fmp5504a universal charger, 850 ma moto oem) from the dock of my previous phone because I need more than one charger (home and office), and it works fine with the Razr Maxx. The difference between 750 and 850 is negligible and the circuitry on the battery regulates current draw and voltage. USB voltage is a standard 5 to 5.1 volts; the internal circuitry on the phone steps it down. The rating of the charger is the max it can deliver, but the actual draw is limited by the circuitry on the phone as part of the charge cycle. See All About Battery Chargers and also Charging Lithium-Ion Batteries. Moto advises against using non-moto chargers (product liability no doubt), but I'm fine with using the moto charger from my last phone. And the charger my local Verizon store sells for the car dock isn't even a Moto.
