US Patent 9356512 Envelope tracking power supply with direct connection to power source

A communication device, such as a smart phone, includes an envelope tracking power supply. The envelope tracking power supply is configured for direct connection to a supply voltage. The direct connection may be made without connection through an intermediate voltage regulator, such as a low drop out regulator. The supply voltage may be a relatively high battery voltage, for example, that would normally result in greater than permissible voltage limits on the transistors used in conventional envelope tracking power supplies.