Systems and methods are described that provide a phantom mobile telephone number that is assigned by the mobile telephone service provider, for business customers andor customers subscribing to the service. The present invention discloses a handheld electronic device for generating a panoramic image formed by a plurality of sub images, the handheld electronic device comprise an input unit, a display unit, an image sensor and a processor. Thus, the dopant profile is established from a horizontal direction, allowing the profile to be controlled. Dynamically biasing the track-and-hold circuit in response to a dynamic biasing current that is a scaled version of the input current significantly increases the maximum peak-to-peak voltage swing allowed at the input of the track-and-hold circuit and enables a corresponding increase in signal-to-noise ratio.