Abstract: A low drop-out regulator and methods for producing a low drop-out voltage are provided. A driver transistor adapted for connecting to an input supply voltage and producing an output voltage is provided. In addition, a mirroring transistor is coupled to the driver transistor and a voltage differential between the drain and the source of the driver transistor is mirrored in the mirroring transistor. The low drop-out regulator operates in both linear and saturation regions of the driver transistor. The driver transistor and the mirroring transistor are implemented in a CMOS process.

Abstract: Methods and apparatus for providing a rail-to-rail op amp are disclosed. The rail-to-rail op amp includes a P-channel input stage and an N-channel input stage. The P-channel input stage includes a set of P-channel MOS transistors and the N-channel input stage includes a set of N-channel MOS transistors. The set of N-channel MOS transistors and the set of P-channel MOS transistors are capable of connecting to an inverting input and a non-inverting input. The op amp further includes a mirroring circuit adapted for sensing current flowing through the P-channel input stage and mirroring a portion of the sensed current. A threshold voltage reduction circuit is adapted for reducing the threshold voltage of the P-channel input stage in proportion to the mirrored current.