An apparatus for providing a connection to a wide area network for voice calls includes a wide area network circuit configured to transmit voice call data packets, a phone connection circuit configured to receive a voice call signal from a phone, a processor circuit configured to generate voice call data packets based on a voice call signal received by the phone connection circuit and a power management circuit configured to switch off at least a part of the apparatus to reach a power down mode of the apparatus, if a supply voltage drops below a supply voltage threshold.