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:
Apr. 19, 1988
Filed:
Apr. 27, 1981
Deepraj S Puar, Sunnyvale, CA (US);
Signetics Corporation, Sunnyvale, CA (US);
Abstract
An on-chip regulated substrate bias voltage generator for an MOS integrated circuit includes a ring oscillator (10) for developing a true signal and its complement. The signals are applied to a charge pump (12) that includes two capacitors (C1 and C2) and a plurality of rectifiers (22, 24, and 26). The charge pump produces a substrate bias voltage (V.sub.BB) which is supplied to the gate of a depletion-mode field-effect transistor (28) whose source receives a reference voltage (V.sub.SS). The transistor forms part of a control circuit (14) coupled to the ring oscillator. In the N-channel case, the charge pumping action on the substrate drives the substrate bias negative until it reaches the sum of the reference voltage and threshold voltage of the depletion-mode transistor. This enables the control circuit to control the operation of the ring oscillator so as to regulate the substrate bias voltage.