Patent ID: 6137153
Filing Date: 2000-10-24
Classification: H01L

Abstract:
A capacitor having a negative threshold voltage, comprising:a P-type substrate;a deep N-well region within said substrate;a P-well region within said N-well region;N+ source and drain regions within said P-well region;a first insulating layer overlying said P-well region;a floating gate overlying said first insulating layer;a second insulating layer overlying said floating gate; anda control sate overlying said second insulating layer, wherein said capacitor is used in a voltage regulator circuit, said circuit comprising:a second capacitor having a first plate coupled to said control gate and a second plate coupled to a voltage to be regulated;an op amp having a first input coupled between said control gate and said first plate of said second capacitor, a second input connected to a reference voltage, and an output connected to a first pass transistor; anda second pass transistor coupled between ground and said control gate, wherein said source, drain, P-well, and deep N-well regions are commonly connected to ground.