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:
Oct. 20, 1998
Filed:
Oct. 24, 1996
Akio Ozawa, Tokyo, JP;
Pioneer Electronic Corporation, Tokyo, JP;
Abstract
The present invention provides a BTL amplifier device with low power consumption and high efficiency which comprises two units of amplifier, a transistor, and a load resistor, and is driven as claimed in output from an operational amplifier as well as from an inverting amplifier. Signals at both edges of the load resistor are supplied to a differential NFB circuit and a fed-back output is inputted to one of the operational amplifiers, while an output signal from the operational amplifier is converted by an absolute value circuit, and then a DC voltage is superimposed on the absolute value signal in a voltage shifting circuit. Voltage from a voltage divider for dividing an output voltage from the voltage shifting circuit and a power voltage to 1/ gain (G) of the two units of amplifier is supplied to a pulse width control circuit, which is compared to a signal from a triangular oscillator so that the pulse width control circuit supplies the compared voltage to a step-up chopper circuit having a pulse width as claimed in a difference between the two voltages, and the chopper supplies a power voltage according to the output voltage.