many of the above implementations, the host device has only a micro-B receptacle rather than a micro-AB receptacle. Although non-standard, micro-B to micro-A receptacle adapters are widely available and used in place of the mandated micro-AB receptacle on these devices. Backward compatibility USB OTG devices are backward-compatible with USB 2.0 (USB 3.0 for SuperSpeed OTG devices) and will behave as standard USB hosts or devices when connected to standard (non-OTG) USB devices. The main exception is that OTG hosts are only required to provide enough power for the products listed on the TPL, which may or may not be enough to connect to a peripheral that is not listed. A powered USB hub may sidestep the issue, if supported, since it will then provide its own power according to either the USB 2.0 or USB 3.0 specifications. Some incompatibilities in both HNP and SRP were introduced between the 1.3 and 2.0 versions of the OTG supplement, which can lead to interoperability issues when using those protocol versions. Charger compatibility Some devices can use their USB ports to charge built-in batteries, while other devices can detect a dedicated charger and draw more than 500 mA (0.5 A), allowing them to charge more rapidly. OTG devices are allowed to use either option. See also Android Open Accessory Development Kit Mobile High-Definition Link, which repurposes the USB on-the-go ID pin Mobile phone accessories USB human interface device class References External links USB