ETD

• chopping stabilization
• impedance boosting
• indirect current feedback
• instrumentation amplifier
• port swapping
• rail to rail

This thesis project focuses on testing an Instrumentation Amplifier with an Indirect Current Feedback architecture (ICFIA), implemented with a UMC 0.18 um process.
The architecture is based on a third order low-pass State Variable Filter (SVF). The main objectives are verifying the effectiveness of two techniques: the first one is Port Swapping, that is employed in order to achieve a highly precise gain, while the second one is Chopping Stabilization, that is a dynamic technique able to reduce low frequency noise. The implementation of these two strategies also results in a great input impedance boosting.
Finally, an input common mode rail-to-rail range is achieved.
In order to improve the flexibility of the amplifier and adapt it to a larger variety of sensors, two values of gains are available, 100 or 5. In this way, this instrumentation amplifier is able to interface sensors whose output voltage can vary between tens up to hundreds of millivolts.