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:
Dec. 05, 1995
Filed:
Nov. 07, 1994
Thomas M Luich, Puyallup, WA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A low leakage, metal oxide semiconductor field effect transistor (MOSFET) charge pump circuit includes P- and N-MOSFET current mirrors, P- and N-MOSFET current switches and an output node. The P-MOSFET current mirror sources an output current which is switched by the P-MOSFET current switch in accordance with a pump-up control signal to provide a pump-up current. The width of the channel of the P-MOSFET current switch is substantially less than the sum of the widths of the channels of the P-MOSFETs of the P-MOSFET current mirror. The N-MOSFET current switch, in accordance with a pump-down control signal, switches a pump-down current which is sunk by the N-MOSFET current mirror. The width of the channel of the N-MOSFET current switch is substantially less than the sum of the widths of the channels of the N-MOSFETs of the N-MOSFET current mirror. The output node couples the P- and N-MOSFET current switches and receives the pump-up current and provides the pump-down current to provide a net charge pump signal suitable for use by a voltage controlled oscillator within a phase lock loop.