US 2003/0067291 A1Published application

Bandgap reference voltage generator with a low-cost, low-power, fast start-up circuit

AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.

InventorHao-Chiao Hong

Life of this patent

Estimating the term…

Loading patent…

Abstract

A bandgap voltage reference generator includes a bandgap voltage reference circuit and a fast startup circuit. The fast start-up circuit, which is cost-efficient and saves power consumption can rapidly start up the bandgap reference voltage circuit coupled thereto. The fast start-up circuit comprises a P-channel MOSFET or an N-channel MOSFET. Upon the bandgap voltage reference generator is powered by an external DC voltage, the bandgap reference generator will possibly operates in power-down operating state. At the time, there exists a large voltage drop between the gate and the source of the P-channel MOSFET (or N-channel MOSFET), and thus a large current flows rapidly through the P-channel MOSFET (or N-channel MOSFET). Voltages of drains of two specific MOSFETs in the bandgap voltage reference circuit will thus be pulled to be substantially the same, and the bandgap voltage reference circuit is brought into normal operating state. The output of the bandgap reference generator is then very close to the bandgap voltage of silicon.

Claims22

Dependent claims

A bandgap voltage reference generator for providing a reference voltage, wherein said bandgap voltage reference generator comprises:

a first current mirror, responsive to an input current of said first current mirror for generating a first output current at a first output node of said first current mirror and a second output current at a second output node of said first current mirror, wherein said second output node is coupled to an output node of said bandgap voltage reference generator for generating said reference voltage at said output node, wherein said output node is coupled to a first potential through a first electric network;
a second current mirror, including a first node, a second node, a third node and a fourth node, wherein said first node is said first output node of said first current mirror and responsive to said first output current of said first current mirror for generating an input current of said second current mirror flowing through said first node to said second node to mirror an output current of said second current mirror flowing through said third node to said fourth node, wherein said second node is coupled to said first potential through a second electric network, and said fourth node is coupled to said first potential through a third electric network;
and
a startup circuit, comprising a first voltage controlled current source device having two ends, wherein one end of said first voltage controlled current source device is coupled to a second potential, while the other end of said first voltage controlled current source device is coupled to said third node, and wherein said first voltage controlled current source device is controlled by a voltage difference between said first node and said third node for generating a pulling current to pull said first node of said second current mirror and said third node to be substantially the same, wherein said second potential is equal to said first potential in voltage.

1 more element

A bandgap voltage reference generator for providing a reference voltage, wherein said bandgap voltage reference generator comprises:

a first current mirror, responsive to an input current of said first current mirror for generating a first output current at a first output node of said first current mirror and a second output current at a second output node of said first current mirror, wherein said second output node of said first current mirror is coupled to an output node of said bandgap voltage reference generator for generating said reference voltage at said output node, wherein said output node of said bandgap voltage reference generator is coupled to a first potential through a first electric network;
a second current mirror, including a first node, a second node, a third node and a fourth node, wherein said first node is said first output node of said first current mirror, and responsive to said first output current of said first current mirror for generating an input current of said second current mirror flowing through said first node to said second node to mirror an output current of said second current mirror flowing through said third node to said fourth node, wherein said second node is coupled to said first potential through a second electric network, and said fourth node is coupled to said first potential through a third electric network;
and
a startup circuit, comprising a first voltage controlled current source device having two ends, wherein one end of said first voltage controlled current source device is coupled to said first node, while the other end of said first voltage controlled current source device is coupled to a second potential, and wherein said first voltage controlled current source device is controlled by a voltage difference between said first node and said third node for generating a pulling current to pull said first node and said third node to be substantially the same in voltage.

1 more element

Dependencies are inferred from the claim text.