US 2003/0222706 A1 · Bandgap reference circuit for low supply voltage applications

Abstract

A bandgap reference-based voltage and current generator has a distributed circuit architecture, to reduce the number of voltage dropping components between voltage supply rails containing bandgap voltage generator circuitry. Base current error compensation circuitry is incorporated into current mirror circuits of the generator to yield a composite current having a desired component, defined exclusively in accordance with the desired bandgap voltage, and a base error component containing the desired bandgap voltage, but modified by a second base current error. By differentially combining these two components, the multiple port output current mirror stage removes the base error component of the composite current, leaving only the desired bandgap-based component at each of plural precision output current ports.

Claims20

Dependent claims

A current generator comprising:

supply voltage terminals across which a differential supply voltage is applied;
a precision voltage generator coupled to said supply voltage terminals and having a precision voltage terminal from which a precision voltage is derived;
and
a multiple output current mirror stage coupled to said precision voltage generator, and being operative to supply a plurality of output currents proportional to said precision voltage, said output currents being exclusive of current errors associated with circuit components of said precision voltage generator and said multiple output current mirror stage.

1 more element

A current generator comprising:

supply voltage terminals across which a differential supply voltage is applied;
and
a multiple output current mirror stage operative to generate a plurality of output currents proportional to a bandgap voltage, and exclusive of current errors associated with circuit components used to produce said bandgap voltage and current errors associated with circuit components of said multiple output current mirror stage.

A method of generating a plurality of output currents that are proportional to a precision reference voltage comprising the steps of:

(a) generating a first, precision DC voltage from a second, differential DC voltage applied across supply voltage terminals, said first DC voltage being less than said second, differential DC voltage;
and
(b) generating a plurality of precision output currents proportional to said first, precision DC voltage, said precision output currents being exclusive of current errors associated with circuit components installed between said supply voltage terminals and used to generate said first, precision DC voltage and said plurality of precision output currents.

Dependencies are inferred from the claim text.

Bandgap reference circuit for low supply voltage applications

Life of this patent

Bandgap reference circuit for low supply voltage applications

Life of this patent

Abstract

Claims20