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:
Nov. 20, 2001
Filed:
Oct. 18, 2000
Angus Chen, Hsin-Chu, TW;
Youngtek Electronics, Hsin-Chu, TW;
Abstract
A low supply voltage for operating an operational amplifier operating as a voltage follower is derived from a high voltage source. Two npn transistors, two Zener diodes and a current source are connected in series across the high voltage source. The input voltage (to the operational amplifier) plus a Zener reference voltage is applied to the base of the transistor near the positive terminal of the high voltage source. Then, a low positive supply voltage V+ nearly equal to the input voltage plus the Zener voltage (Vi+Vz) is derived at the emitter. This low positive supply voltage V− is derived by dropping V+ through the two series Zener diodes to obtain a low negative supply voltage equal to (Vi−Vz).