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. 15, 1992
Filed:
Mar. 16, 1992
Toshihiko Shigenari, Nara, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A balanced modulation circuit includes first, second, and third differential amplifiers. The first differential amplifier includes first and second transistors (Q11, Q12) having the emitters connected to first and second constant-current sources (CS11, CS12) and also connected with each other through a resistor, the collectors connected to the power supply line through respective base-collector-coupled transistors (Q13, Q14) used as diodes, and the bases connected to a first voltage source (V11) through respective resistors (R11, R12). The second differential amplifier includes third and fourth transistors (Q17, Q18) having the emitters connected to the collector of a transistor (Q15) whose base is connected to the base of the transistor (Q14) and whose emitter is connected to the power supply line, the bases of the third and fourth transistors (Q17, Q18) are connected to a second voltage source (V12) through respective resistors, and the collectors are connected to the ground line through respective resistors. The third differential amplifier includes fifth and sixth transistors (Q19, Q20) having the emitters connected to the collector of a transistor (Q16) whose base is connected to the base of the transistor (Q13) and whose emitter is connected to the power supply line, the bases of the fifth and sixth transistors (Q19, Q20) are respectively connected to the bases of the fourth and third transistors (Q18, Q17), and the collectors are respectively connected to the collectors of the third and fourth transistors (Q17, Q18).