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. 28, 2015
Filed:
Jun. 26, 2014
Hong Kong Applied Science & Technology Research Institute Company Limited, Hong Kong, HK;
Tat Fu Chan, Hong Kong, HK;
Abstract
An Amplitude-Shifted-Keyed (ASK) modulator/transmitter has fall time enhanced by pulsing pull-up and pull-down enhancement switches on for a short period of time after a data transition. The enhancement switches draw energy from a coupling capacitor to more rapidly reduce an amplitude of the carrier wave being output. An input carrier wave is applied to gates of p-channel and n-channel current sources that drive the coupling capacitor. Gates of the n-channel and p-channel enhancement switches also receive the input carrier wave when data is high, but are disabled when data is low. Multiple p-channel and n-channel transistors may be used in parallel for each current source or enhancement switch. Each of the multiple transistors in parallel has a gate that is AND'ed with an index signal. The index signals are programmable and determine how many of the parallel transistors are enabled, thus determining the aggregate current.