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:
Jun. 11, 1996
Filed:
Jun. 07, 1995
Michael D Smith, Lewisville, TX (US);
Dallas Semiconductor Corporation, Dallas, TX (US);
Abstract
A bidirectional voltage to current converter circuit with extended dynamic range includes a first and second operational amplifier in which the input voltage terminal is connected to the negative input of both operational amplifiers. The outputs of the operational amplifiers each directly drive the gates of two transistors which operate as a current mirror circuit. The current mirror transistors associated with the first operational amplifier are p-channel transistors with their sources connected to VDD, and the two transistors driven by the second operational amplifier are n-channel transistors with their sources connected to ground. The drains of the first p-channel transistor and the first n-channel transistor are coupled back to the positive inputs of the first and second operational amplifiers respectively; and also each drain is separately connected to one end of a resistor, the other ends of the two resistors are connected together and to a reference voltage. The drains of the second p-channel transistor and the second n-channel transistor are connected together to form a current output terminal.