The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 02, 1999
Filed:
Aug. 14, 1997
Michael G Tuthill, Limerick, IE;
Analog Devices, Inc., Norwood, MA (US);
Abstract
A switching bandgap reference circuit with compounded .DELTA.V.sub.BE includes an amplifier having an output, an inverting input and a non-inverting input; a first PN junction connected to the non-inverting input; a second PN junction connected to the inverting input through an input capacitor; a low current source and a high current source; a switching device for applying in the auto zero mode the low current source to a first terminal of the first PN junction and the high current source to a first terminal of the second PN junction for establishing the V.sub.BE, of the first junction at both the inputs of the amplifier and for applying in the valid reference mode the high current source to the first terminal of the first PN junction and the low current source to the first terminal of the second PN junction for establishing the positive .DELTA.V.sub.BE, of the first PN junction to both the inputs of the amplifier and applying the negative .DELTA.V.sub.BE2 of the second PN junction to the input capacitor to produce a voltage of .DELTA.V.sub.BE1 plus (-.DELTA.V.sub.BE2) across the input capacitor; a feedback capacitor connected between the output and inverting input of the amplifier to define the gain on the combined .DELTA.V.sub.BE voltages to produce a temperature stabilized voltage at the output of the amplifier and a reset switching device for discharging the feedback capacitor and enabling the amplifier to equalize its inputs in the auto zero mode.