A mobile tag tracking system for providing mobile security monitoring is provided. A base having an open interior is fixedly or removably secured in surrounding relation to the display screen and extends. A first terminal of the first transistor is coupled to an external voltage. The periodic structures of the first and second sections are each formed on one of the two layers of the device, respectively. Embodiments of the present invention are particularly useful for fleshy, blobby animation objects such as human characters, although the techniques can be used for other objects having different characteristics. A more complex controllable transconductance inverting amplifier may be used, replacing PFET 154 with series connected PFETs 164, 166.