Abstract: A circuit for tuning a transconductance amplifier includes a first transconductance amplifier outputting a first current from its output, a second transconductance amplifier outputting a second current from an output that is coupled to the output of the first transconductance amplifier, and a feedback loop. The feedback loop provides a control signal that varies with a difference between the first current and the second current and is used to adjust the transconductance of the second transconductance amplifier.

Abstract: The present invention is a method and apparatus for effectuating managed child, youth, young adult, or dependant commerce. The present invention conveniently allows parents, guardians or trustees to more effectively manage, control, and monitor the spending patterns of their dependants while simultaneously relieving the child of the burden of carrying and maintaining cash or checks. It also establishes a streamlined method for providers of goods and services to those dependants to be able to offer and provide those goods to children and for those sellers to receive payment for their services in a more effective manner than currently available. The present invention has specific functionality between parents, children, educational institutions, and goods and service providers.

Abstract: A circuit for stabilizing the gain-bandwidth product of analog circuits containing bipolar devices which determine the gm is disclosed. The stabilization circuit is formed to generate a reference current that is proportional to a reference capacitance C.sub.S and the thermal voltage V.sub.T. The reference current is ultimately mirrored (as the bias current) into the bipolar devices which determine the gm within the analog circuit. Since the transconductance gm of a bipolar device can be expressed as collector current, I.sub.C, divided by V.sub.T, the thermal voltage factor of the bias current itself will "cancel" the thermal voltage factor present in the transconductance. The effects related to the remaining variable, the capacitance, will be eliminated as long as the reference capacitance is formed to "track" the analog circuit capacitance by using similar types of capacitance to implement both capacitors and forming both the stabilization circuit and the analog circuit on the same silicon chip.