Patent ID: 7902801
Filing Date: 2011-03-08
Classification: G05F

Abstract:
1. A stability compensation circuit for a low dropout regulator, the low dropout regulator including a driver transistor, the circuit comprising: a first compensation transistor having a gate coupled to a gate of the driver transistor, a source coupled to an unregulated input voltage, and a drain; a compensation capacitor coupled between the gate and the drain of the compensation transistor; a second compensation transistor having a gate coupled to a drain of the driver transistor, a drain coupled to the unregulated input voltage, and a source; a resistor coupled between the drain of the first compensation transistor and the source of the second compensation transistor; and a source of bias current coupled to the source of the second compensation transistor, wherein the compensation capacitor remains in an accumulation region at no load current to provide a maximum capacitance, and the capacitance of said compensation capacitor decreases with a load current during a higher load current region.