Portable electronic devices often need to electrically connect to other electrical devices in order to be recharged and in order to exchange data, such as software updates or usage data. Typically data is transferred over one set of electrical contacts and power is transferred over another set of electrical contacts.
In order to ensure that the correct electrical connections are made, so that the data contacts on one device mate with the data contacts on the other device, and similarly the power contacts on one device mate with the power contacts on the other device, prior systems have relied on mechanical means to prevent incorrect connection. This means that the devices can only connect in one orientation, which can be difficult and cause irritation for end users.