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:
Jan. 04, 1994
Filed:
Jun. 18, 1992
Carver A Mead, Pasadena, CA (US);
Federico Faggin, Los Altos Hills, CA (US);
Synaptics, Incorporated, San Jose, CA (US);
Abstract
A plurality of integrating photosensors is disposed in an array of rows and columns, with a given row select line connected to the gates of P-channel MOS transistors associated with that given row and a given column sense line connected to the drains of the P-channel MOS transistors associated with that given column. A sense amplifier is associated with each column. An integrating sense amplifier according to the present invention includes an amplifying element having an inverting input and a non-inverting input. The non-inverting input is connected to a source of reference voltage the inverting input is connected to a sense line. A P-channel balance transistor is connected between the inverting input and the output of the amplifying element and a capacitor is also connected between the inverting input and output of the amplifying element. A capacitor, preferably a varactor element, is connected between the output and the inverting input of the amplifying element. An exponential feedback element may be provided in the sense amplifiers for signal compression at high light levels.