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. 13, 2010
Filed:
Dec. 04, 2007
Shiah Siew Wong, Singapore, SG;
Wee Sien Hong, Singapore, SG;
Tien Yew Kang, Singapore, SG;
Jing Sun, Singapore, SG;
Shiah Siew Wong, Singapore, SG;
Wee Sien Hong, Singapore, SG;
Tien Yew Kang, Singapore, SG;
Jing Sun, Singapore, SG;
Panasonic Corporation, Osaka, JP;
Panasonic Semiconductor Asia Pte. Ltd., Singapore, SG;
Abstract
A slew rate control circuit in output driver of switching circuit to prevent power ground undershoot is introduced. The gate capacitance of lower power transistor is first fast discharged to ensure the operation of the output signal. The gate capacitance of lower power transistor is then slowly discharged to limit OUT SLEW RATE. The gate capacitance of lower power transistor is further slowly discharged when the power ground level is below common ground. With above controlling, the gate voltage slew rate of lower power transistor is reduced when the lower power transistor is almost fully turned OFF. Therefore, undershoot at the power ground is avoided. Similar slew rate control circuit can also be derived in output driver of switching circuit to prevent PVCC overshoot.