Patent ID: 6084391
Filing Date: 2000-07-04
Classification: G05F

Abstract:
A bandgap reference voltage generating circuit comprising a first unitary circuit having a first transistor of a first conductivity type and a switching second transistor of a second conductivity type opposite to said first conductivity type, which are connected in the named order in series between a first power supply voltage and a second power supply voltage, a second unitary circuit having a first resistor, a third transistor of said first conductivity type, and a switching fourth transistor of said second conductivity type which are connected in series in the named order between said first power supply voltage and said second power supply voltage, a third unitary circuit having a second resistor and a switching fifth transistor of said second conductivity type which are connected in series in the named order between said first power supply voltage and said second power supply voltage, and a fourth unitary circuit having a switching sixth transistor of said first conductivity type and a load seventh transistor of said second conductivity type which are connected in series in the named order between said first power supply voltage and said second power supply voltage, said sixth transistor being turned on in response to a bias voltage applied to a control electrode of said sixth transistor, a control electrode of said second transistor, a control electrode of said fourth transistor, a control electrode of said fifth transistor, and an output end of a main current path of said fourth transistor being connected one another, a control electrode of said first transistor, a control electrode of said third transistor and an input end of a main current path of said first transistor being connected one another to form a current mirror circuit, an input end of a main current path of said third transistor being connected to an input end of a main current path of said sixth transistor through a capacitor, so that when said sixth transistor is turned on in response to said bias voltage applied to said control electrode of said sixth transistor, a potential on one end of said capacitor connected to the input end of the main current path of said sixth transistor is dropped down, with the result that said second transistor and said fourth transistor are turned on so that the potential on the control electrode of said first and third transistors is quickly fixed, and a stabilized reference voltage is generated at a connection node between said second resistor and said fifth transistor.