SOI integrated circuits technology offer several advantages over bulk devices in terms of speed, isolation, density, yield and performance in the sub-micron arena. Despite these advantages, the use of SOI integrated circuits has its challenges. For example, consider a floating body of an SOI MOSFET (e.g., a field-effect-transistor (FET)) that has no contact to the body node because it resides on an insulated substrate. Because it is not contacted, it is difficult to ascertain the voltage at the floating body. Without having accurate voltage measurements of the floating body, it becomes difficult for a device engineer to model the behavior of a particular SOI MOSFET device. For example, gate voltage and drain voltage of a SOI MOSFET device are readily ascertainable, however, because a measurement for the floating body voltage is difficult to accurately ascertain, a device engineer cannot model the drain current which is a function of the gate voltage, drain voltage and floating body voltage. In order to overcome this challenge, body-contacted SOI MOSFET devices have been used to obtain a measure of floating body voltage. However, obtaining an accurate measure of the floating body voltage of a body-contacted SOI MOSFET device is a challenge for device engineers. In particular, when a floating body node is coupled to a voltmeter to obtain a measure of the floating body voltage, there will be a low flowing current that loads the node, which causes the floating body voltage to change. Therefore, any measurement of the floating body voltage at the node will be erroneous due to the current loading caused by the voltmeter.
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