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:
Oct. 20, 1998
Filed:
Oct. 24, 1996
Gianluca Colli, Santa Clara, CA (US);
Massimiliano Brambilla, San Jose, CA (US);
STMicroelectronics, Inc., Carrollton, TX (US);
Abstract
A voltage ramp generator for a driver circuit is provided to give an output that is highly linear between zero and a maximum voltage has a combination of current sources or generators for charging and discharging a capacitor, with discharging performed by sequencing two different types of current sources. A first current source on the discharge side of the capacitor has transistors in cascode connected current mirrors and takes the capacitor voltage to a low value but not as low as zero. A second current source of a basic or simple current mirror then takes the capacitor voltage substantially to zero. The voltage ramp generator meets the requirements of high performance, integrated, driver circuits, particularly for achieving complete turn-off of a power device such as a DMOS transistor in a high side cascoded transistors goes up to a threshold near the full supply driver. It is optional to have two current sources for charging, also, where a first source with voltage and than a second source, in a basic current mirror, continues charging substantially to the supply voltage.