An input stage employs low-voltage MOSFETs as input devices for an operational amplifier circuit that operates at common mode voltages that may exceed the gate-oxide breakdown voltage of the input devices. Also, the input stage is arranged for relatively low noise. The input stage is arranged to detect...http://www.google.de/patents/US6998907?utm_source=gb-gplus-sharePatent US6998907 - Apparatus and method for receiving high-common mode voltage range signals with low-voltage devices
